ADP5014 [ADI]
Integrated Power Solution with Quad Low Noise Buck Regulators;型号: | ADP5014 |
厂家: | ADI |
描述: | Integrated Power Solution with Quad Low Noise Buck Regulators |
文件: | 总34页 (文件大小:827K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
Integrated Power Solution
with Quad Low Noise Buck Regulators
Data Sheet
ADP5014
FEATURES
TYPICAL APPLICATION CIRCUIT
Input voltage range: 2.75 V to 6.0 V
ADP5014
VREF
R
RT
RT
Programmable output voltage range: 0.5 V to 0.9 × PVINx
Low output noise: ~25 μV rms when VOUT ≤ VREF
1.0ꢀ output accuracy over full temperature range
500 kHz to 2.5 MHz adjustable switching frequency
Power regulation
Channel 1 and Channel 2: programmable 2 A/4 A sync
buck regulators, or single 8 A output in parallel
Channel 3 and Channel 4: programmable 1 A/2 A sync
buck regulators, or single 4 A output in parallel
Flexible parallel operation
C1
OSC
REF
EN1/ENALL
EN2/DL12
EN3/UV
CFG1
CFG2
GPIO
LOGIC DECODER
EN4/DL34
AVIN
FB1
2.75V TO 6.0V
PVIN1
SW1
C2
L1
CH 1
LOW-NOISE BUCK
(2A/4A)
VOUT1
C3
PVIN1
VSET1
VREF
PGND1
COMP1
PVIN2
FB2
Precision enable with 0.6 V threshold
Manual or sequence mode for power-up and power-down
sequence
SW2
C4
CH 2
LOW-NOISE BUCK
(2A/4A)
L2
VOUT2
C5
VREF
VSET2
PGND2
Selective FPWM or PSM operation mode
Precision undervoltage comparator
Frequency synchronization input or output
Active output discharge switch
Power-good flag on selective channels via factory fuse
UVLO, OVP, OCP, and TSD protection
COMP2
PVIN3
L3
VOUT3
C7
SW3
FB3
C6
VREF
CH 3
VSET3
LOW-NOISE BUCK
(1A/2A)
PGND3
COMP3
40-lead, 6 mm × 6 mm LFCSP package
−40°C to +125°C junction temperature
PVIN4
L4
VOUT4
C9
SW4
FB4
C8
VREF
CH 4
LOW-NOISE BUCK
(1A/2A)
VSET4
APPLICATIONS
PGND4
COMP4
RF transceiver, high speed analog-to-digital converter
(ADC)/digital-to-analog converter (DAC), mixed signal ASIC
FPGA and processor applications
AGND
EXPOSED PAD
Security and surveillance
Figure 1.
Medical applications
GENERAL DESCRIPTION
The ADP5014 combines four high performance, low noise
buck regulators in a 40-lead LFCSP package. Relying on its low
output noise (~25 μV rms when VOUT ≤ VREF), the low noise
buck regulator enables the powering up of the noise sensitive
signal chain products.
The ADP5014 features two enable modes. The manual mode
has four individual precision enable pins to enable each
regulator manually. Alternatively, the sequence mode has one
grouped precision enable signal with programmable power-up
and power-down delay timers on each rail for specific rail
sequence requirements.
All channels in the ADP5014 integrate high-side and low-side
power metal-oxide semiconductor field effect transistors
(MOSFET). Channel 1 and Channel 2 deliver a programmable
output current of 2 A or 4 A. Combining Channel 1 and
Channel 2 in a parallel configuration provides a single output
with up to 8 A of current.
The switching frequency of the ADP5014 can be programmed
or synchronized to an external clock from 500 kHz to 2.5 MHz.
The ADP5014 offers other key features like selective forced
pulse width modulation (FPWM)/power saving mode (PSM),
an undervoltage output (UVO), active output discharge, and a
power-good flag. Other safety features include input under-
voltage lockout (UVLO), overvoltage protection (OVP),
overcurrent protection (OCP) and thermal shutdown (TSD).
Channel 3 and Channel 4 deliver a programmable output current
of 1 A or 2 A. Combining Channel 3 and Channel 4 in a parallel
configuration can provide a single output with up to 4 A of
current.
Rev. A
Document Feedback
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rights of third parties that may result from its use. Specifications subject to change without notice. No
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Tel: 781.329.4700 ©2017–2019 Analog Devices, Inc. All rights reserved.
Technical Support
www.analog.com
ADP5014
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Overvoltage Protection.............................................................. 20
Undervoltage Lockout ............................................................... 20
Active Output Discharge Switch .............................................. 21
Thermal Shutdown .................................................................... 21
Applications Information .............................................................. 22
ADIsimPower Design Tool ....................................................... 22
Programming the Output Voltage ........................................... 22
Voltage Conversion Limitations............................................... 22
Current-Limit Setting................................................................ 23
Soft Start Setting......................................................................... 23
Inductor Selection ...................................................................... 23
Output Capacitor Selection....................................................... 24
Input Capacitor Selection.......................................................... 24
Programming the UVLO Input................................................ 24
Compensation Components Design ....................................... 24
Power Dissipation....................................................................... 25
Junction Temperature................................................................ 26
Design Examples ............................................................................ 27
Setting the Switching Frequency.............................................. 27
Setting the Output Voltage........................................................ 27
Setting the Configuations (CFG1 and CFG2)........................ 27
Selecting the Inductor................................................................ 27
Selecting the Output Capacitor ................................................ 28
Designing the Compensation Network................................... 28
Low Noise Output Design......................................................... 28
PCB Layout Recommendations.................................................... 30
Typical Application Circuits ......................................................... 31
Factory Programmable Options................................................... 33
Factory Default Options............................................................ 33
Outline Dimensions....................................................................... 34
Ordering Guide .......................................................................... 34
Applications....................................................................................... 1
Typical Application Circuit ............................................................. 1
General Description......................................................................... 1
Revision History ............................................................................... 2
Detailed Functional Block Diagram .............................................. 3
Specifications..................................................................................... 4
Buck Regulator Specifications .................................................... 5
Absolute Maximum Ratings............................................................ 7
Thermal Resistance ...................................................................... 7
ESD Caution.................................................................................. 7
Pin Configuration and Function Descriptions............................. 8
Typical Performance Characteristics ........................................... 10
Theory of Operation ...................................................................... 14
Buck Regulator Operational Modes......................................... 14
Low Noise Architecture............................................................. 14
Internal Reference (VREF)........................................................ 14
Adjustable Output Voltage ........................................................ 14
Function Configurations (CFG1 and CFG2) ......................... 15
Parallel Operation....................................................................... 16
Manual/Sequence Mode............................................................ 16
General Purpose Input/Output (GPIO).................................. 18
Oscillator ..................................................................................... 18
Synchronization Input/Output................................................. 19
Power-Good Function ............................................................... 19
UV Comparator (Sequence Mode Only) ................................ 19
Soft Start ...................................................................................... 20
Startup with Precharged Output .............................................. 20
Current-Limit Protection .......................................................... 20
Frequency Fold Back.................................................................. 20
Short-Circuit Protection (SCP) ................................................ 20
REVISION HISTORY
8/2019—Rev. 0 to Rev. A
6/2017—Revision 0: Initial Version
Changes to Parallel Operation Section........................................ 16
Updated Outline Dimensions ....................................................... 34
Rev. A | Page 2 of 34
Data Sheet
ADP5014
DETAILED FUNCTIONAL BLOCK DIAGRAM
CHANNEL 1 – BUCK
UVLO1
PVIN1
EN1/ENALL
EN_BUF
+
–
+
0.6V
3µA
ACS1
–
1µA
+
–
HICCUP
MODE
PVIN1
CLK1
Q1
Q2
OCP
DRIVER
SLOPE
COMP
+
CMP1
–
SW1
COMP1
VSET1
PVIN1
CONTROL LOGIC
AND MOSFET
DRIVER WITH
ANTICROSS
+
DRIVER
EA1
–
CLK1
PROTECTION
PGND1
FREQ
FOLDBACK
ZERO
CROSS
FB1
OVP
LATCH-UP
–
+
NEG CURRENT
CMP
0.9
1.15
PWRGD1
VID1
+
–
CURRENT BALANCE
EN2/DL12
COMP2
PVIN2
SW2
CHANNEL 2 – BUCK
DUPLICATE
CHANNEL 1
VSET2
FB2
PGND2
OSCILLATOR
RT
CLK
CFG1
CFG2
HOUSE-KEEPING
LOGIC
FUNCTION
DECODER
REF
VREF
AVIN
UVLO
GPIO
CHANNEL 3 – BUCK
UVLO3
PVIN3
EN_BUF
EN3/UV
+
–
+
0.6V
3µA
ACS3
–
1µA
+
HICCUP
MODE
PVIN3
CLK3
Q5
–
OCP
DRIVER
SLOPE
COMP
+
CMP3
SW3
–
PVIN3
COMP3
VSET3
Q6
CONTROL LOGIC
AND MOSFET
DRIVER WITH
ANTICROSS
+
DRIVER
EA3
–
CLK3
PGND3
PROTECTION
FREQ
FOLDBACK
ZERO
CROSS
FB3
OVP
LATCH-UP
–
+
NEG CURRENT
CMP
0.9
1.15
PWRGD3
VID3
+
–
CURRENT BALANCE
PVIN4
SW4
EN4/DL34
COMP4
VSET4
FB4
CHANNEL 4 – BUCK
DUPLICATE
CHANNEL 3
PGND4
Figure 2.
Rev. A | Page 3 of 34
ADP5014
Data Sheet
SPECIFICATIONS
VIN = 5 V, T J = −40°C to +125°C for minimum and maximum specifications, and TA = 25°C for typical specifications, unless otherwise noted.
Table 1.
Parameter
Symbol
Min
Typ
Max
Unit
Test Conditions/Comments
INPUT SUPPLY VOLTAGE RANGE
VIN
2.75
6.0
V
AVIN, PVIN1, PVIN2, PVIN3,
PVIN4 pins
QUIESCENT CURRENT
AVIN, PVIN1, PVIN2, PVIN3,
PVIN4 pins
Operating Quiescent Current
Shutdown Current
IQ
ISHDN
UVLO
5.4
47
7.0
85
mA
µA
No switching, all ENx pins high
All ENx pins low
UNDERVOLTAGE LOCKOUT
AVIN, PVIN1, PVIN2, PVIN3,
PVIN4 pins
Threshold, Rising
Threshold, Falling
Hysteresis
VUVLO-RISING
VUVLO-FALLING
VHYS
2.65
2.40
0.25
2.75
V
V
V
2.30
REFERENCE
Output Voltage
VREF
2.0
V
Accuracy
Maximum Load
−1.0
1
+1.0
%
mA
OSCILLATOR CIRCUIT
Switching Frequency Range
Switching Frequency
Sync Input
500
1000
2500
1400
kHz
kHz
fSW
1200
RRT = 82.5 kΩ
Input Clock Range
Input Clock Pulse Width
Minimum On Time
Minimum Off Time
Input Clock High Voltage
Input Clock Low Voltage
Sync Output
fSYNC
500
2500
kHz
tSYNC_MIN_ON
tSYNC_MIN_OFF
VH(SYNC)
100
100
1.3
ns
ns
V
VL(SYNC)
0.4
V
Clock Frequency
Positive Pulse Duty Cycle
Rise or Fall Time
fCLK
fSW
50
10
VAVIN
kHz
%
ns
V
tCLK_PULSE_DUTY
tCLK_RISE_FALL
VH(SYNC_OUT)
High Level Voltage
PRECISION ENABLING
High Level Threshold
Low Level Threshold
Source Current
EN1, EN2, EN3, EN4 pins
VTH_H(EN)
VTH_L(EN)
ITH_L(EN)
0.6
0.57
4
0.65
48
V
V
µA
0.52
6
Below the falling threshold
DELAY TIMER
Programmable Delay Timer Range
Delay Timer
tDELAY
tDELAY
ms
ms
ms
6
48
Timer ×1 option
Timer ×8 option
POWER GOOD
Internal Power-Good Rising Threshold VPWRGD(RISE)
87
90
3
50
2
16
0.1
70
93
%
%
µs
ms
ms
µA
mV
Internal Power-Good Hysteresis
Internal Power-Good Falling Delay
Rising Delay for PWRGD Pin
VPWRGD(HYS)
tPWRGD_FALL
tPWRGD_PIN_RISE
Timer ×1 option
Timer ×8 option
Leakage Current for PWRGD Pin
Output Low Voltage for PWRGD Pin
IPWRGD_LEAKAGE
VPWRGD_LOW
1
150
IPWRGD = 1 mA
Rev. A | Page 4 of 34
Data Sheet
ADP5014
Parameter
Symbol
Min
Typ
Max
Unit
Test Conditions/Comments
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
TSHDN
THYS
150
15
°C
°C
BUCK REGULATOR SPECIFICATIONS
VIN = 5 V, f SW = 1.2 MHz for all channels, TJ = −40°C to +125°C for minimum and maximum specifications, and TA = 25°C for typical
specifications, unless otherwise noted.
Table 2.
Parameter
Symbol
Min
Typ
Max
Unit
Test Conditions/Comments
CHANNEL 1 SYNC BUCK REGULATOR
Load Current
ILOAD1
4
A
Output Characteristics
VFB1 Voltage Accuracy
−40°C ≤ TJ ≤ +125°C
VSET1 = VREF
VSET1 = ½ × VREF
VFB1
−0.6
−1.0
+0.6
+1.0
0.1
%
%
µA
μA
Feedback Bias Current
VSET1 Bias Current
SW1 Pin
IFB1
IVSET1
0.1
High-Side Power Field Effect
Transistor (FET) On Resistance
Low-Side Power FET
On Resistance
RDS(ON)1H
RDS(ON)1L
ITH(ILIM1)
49
37
80
60
mΩ
mΩ
Pin to pin measurement
Pin to pin measurement
Current-Limit Threshold
5.2
2.5
6.9
3.5
60
8.6
4.5
90
A
A
ns
ns
RCFG1 = 0 kΩ
RCFG1 = 17.8 kΩ
fSW = 500 kHz to 2.5 MHz
fSW = 500 kHz to 2.5 MHz
Minimum On Time
Minimum Off Time
Error Amplifier, COMP1 Pin
EA Transconductance
Soft Start Time
tMIN_ON1
tMIN_OFF1
50
80
gm1
tSS1
700
2
800
2
16
900
16
µS
ms
ms
ms
ms
Ω
Timer ×1 option
Timer ×8 option
Programmable Soft Start Range
Hiccup Time
COUT Discharge Switch On
Resistance
tHICCUP1
RDIS1
7 × tSS1
85
CHANNEL 2 SYNC BUCK REGULATOR
Load Current
ILOAD2
4
A
Output Characteristics
VFB2 Voltage Accuracy
−40°C ≤ TJ ≤ +125°C
VSET2 = VREF
VSET2 = ½ × VREF
VFB2
−0.6
−1.0
+0.6
+1.0
0.1
%
%
µA
µA
Feedback Bias Current
VSET2 Bias Current
SW2 Pin
IFB2
IVSET2
0.1
High-Side Power FET On
Resistance
Low-Side Power FET On
Resistance
RDS(ON)2H
RDS(ON)2L
ITH(ILIM2)
49
37
80
60
mΩ
mΩ
Pin to pin measurement
Pin to pin measurement
Current-Limit Threshold
5.2
2.5
6.9
3.5
60
8.6
4.5
90
A
A
ns
ns
RCFG1 = 0 kΩ
RCFG1 = 17.8 kΩ
fSW = 500 kHz to 2.5 MHz
fSW = 500 kHz to 2.5 MHz
Minimum On Time
Minimum Off Time
tMIN_ON2
tMIN_OFF2
50
80
Error Amplifier, COMP2 Pin
Transconductance
gm2
700
800
900
µS
Rev. A | Page 5 of 34
ADP5014
Data Sheet
Parameter
Symbol
Min
Typ
2
16
Max
Unit
ms
ms
ms
ms
Ω
Test Conditions/Comments
Timer ×1 option
Timer ×8 option
Soft Start Time
tSS2
Programmable Soft Start Range
Hiccup Time
COUT Discharge Switch On
Resistance
2
16
tHICCUP2
RDIS2
7 × tSS2
85
CHANNEL 3 SYNC BUCK REGULATOR
Load Current
ILOAD3
2
A
Output Characteristics
VFB3 Voltage Accuracy
−40°C ≤ TJ ≤ +125°C
VSET3 = VREF
VSET3 = ½ × VREF
VFB3
−0.6
−1.0
+0.6
+1.0
0.1
%
%
µA
µA
Feedback Bias Current
VSET3 Bias Current
SW3 Pin
IFB3
IVSET3
0.1
High-Side Power FET On
Resistance
Low-Side Power FET On
Resistance
RDS(ON)3H
RDS(ON)3L
ITH(ILIM3)
95
73
135
110
mΩ
mΩ
Pin to pin measurement
Pin to pin measurement
Current-Limit Threshold
2.5
1.2
3.5
1.8
60
4.5
2.4
90
A
A
ns
ns
RCFG1 = 0 kΩ
RCFG1 = 17.8 kΩ
fSW = 500 kHz to 2.5 MHz
fSW = 500 kHz to 2.5 MHz
Minimum On Time
Minimum Off Time
Error Amplifier, COMP3 Pin
EA Transconductance
Soft Start Time
tMIN_ON3
tMIN_OFF3
50
80
gm3
tSS3
700
2
800
2
16
900
16
µS
ms
ms
ms
ms
Ω
Timer ×1 option
Timer ×8 option
Programmable Soft Start Range
Hiccup Time
COUT Discharge Switch On Resistance RDIS3
CHANNEL 4 SYNC BUCK REGULATOR
tHICCUP3
7 × tSS3
85
Load Current
ILOAD4
2
A
Output Characteristics
VFB4 Voltage Accuracy
−40°C ≤ TJ ≤ +125°C
VSET4 = VREF
VSET4 = ½ × VREF
VFB4
−0.6
−1.0
+0.6
+1.0
0.1
%
%
µA
μA
Feedback Bias Current
VSET4 Bias Current
SW4 Pin
IFB4
IVSET4
0.1
High-Side Power FET On
Resistance
Low-Side Power FET On
Resistance
RDS(ON)4H
RDS(ON)4L
ITH(ILIM4)
95
73
135
110
mΩ
mΩ
Pin to pin measurement
Pin to pin measurement
Current-Limit Threshold
2.5
1.2
3.5
1.8
60
4.5
2.4
90
A
A
ns
ns
RCFG1 = 0 kΩ
RCFG1 = 17.8 kΩ
fSW = 500 kHz to 2.5 MHz
fSW = 500 kHz to 2.5 MHz
Minimum On Time
Minimum Off Time
Error Amplifier, COMP4 Pin
EA Transconductance
Soft Start Time
tMIN_ON4
tMIN_OFF4
50
80
gm4
tSS4
700
2
800
2
16
900
16
µS
ms
ms
ms
ms
Ω
Timer ×1 option
Timer ×8 option
Programmable Soft Start Range
Hiccup Time
COUT Discharge Switch On Resistance RDIS4
tHICCUP4
7 × tSS4
85
Rev. A | Page 6 of 34
Data Sheet
ADP5014
ABSOLUTE MAXIMUM RATINGS
Table 3.
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
Parameter
Rating
AVIN to Ground
PVIN1 to PGND1
PVIN2 to PGND2
PVIN3 to PGND3
PVIN4 to PGND4
SW1 to PGND1
SW2 to PGND2
SW3 to PGND3
SW4 to PGND4
PGND to Ground
CFG1, CFG2 to Ground
EN1/ENALL, EN2/DL12, EN3/UV,
EN4/DL34 to Ground
GPIO to Ground
RT to Ground
VREF to Ground
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to + 0.3 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
THERMAL RESISTANCE
Thermal performance is directly linked to printed circuit board
(PCB) design and operating environment. Close attention to
PCB thermal design is required.
Table 4. Thermal Resistance
Package Type
θJA
θJC
Unit
CP-40-10
40
11.1
°C/W
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
−0.3 V to +6.5 V
ESD CAUTION
FB1, FB2, FB3, FB4 to Ground 1
COMP1, COMP2, COMP3, COMP4
to Ground
VSET1, VSET2, VSET3, VSET4 to
Ground
−0.3 V to +6.5 V
Storage Temperate Range
Operational Junction Temperature
Range
−65°C to +150°C
−40°C to +125°C
1 The rating for the FB1, FB2, FB3, and FB4 pins applies to the adjustable
output voltage models of the ADP5014.
Rev. A | Page 7 of 34
ADP5014
Data Sheet
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
FB3
COMP3
PVIN3
SW3
1
2
3
4
5
6
7
8
9
30 PVIN1
29
28
SW1
SW1
27 PGND1
ADP5014
PGND3
PGND4
SW4
26
25
PGND1
PGND2
TOP VIEW
(Not to Scale)
24 PGND2
23 SW2
22 SW2
21 PVIN2
PVIN4
COMP4
FB4 10
NOTES
1. EXPOSED PAD. THE EXPOSED PAD MUST BE
CONNECTED AND SOLDERED TO AN EXTERNAL
GROUND PLANE.
Figure 3. Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
FB3
Feedback Sensing Input for Channel 3.
2
3
4
COMP3
PVIN3
SW3
Error Amplifier Output for Channel 3. Connect a resistor capacitor (RC) network from this pin to ground.
Power Input for Channel 3.
Switching Node Output for Channel 3.
5
6
7
PGND3
PGND4
SW4
Power Ground for Channel 3
Power Ground for Channel 4.
Switching Node Output for Channel 4.
8
9
10
11
PVIN4
COMP4
FB4
Power Input for Channel 4.
Error Amplifier Output for Channel 4. Connect an RC network from this pin to ground.
Feedback Sensing Input for Channel 4.
General-Purpose Input or Output Signal. This pin can be configured as power good, synchronization clock
output (CLK-OUT) or undervoltage comparator output (UVO).
GPIO
12
13
EN4/DL34
EN3/UV
Enable Input for Channel 4 in Manual Mode (EN4).
Delay Timer Setting for Channel 3 and Channel 4 in Sequence Mode (DL34). Connect one resistor from this pin
to ground to program the start-up and shutdown sequence delay timer for Channel 3 and Channel 4.
Enable Input for Channel 3 in Manual Mode (EN3).
Under Voltage Comparator Input in Sequence Mode (UV).
14
15
16
CFG2
System Configuration Pin 1. Connect one resistor from this pin to ground to program sequence or manual
mode, the delay timer, PSM or FPWM operation mode, and GPIO mapping for all channels.
System Configuration Pin 2. Connect one resistor from this pin to ground to program current limit, and the
parallel output for all channels.
CFG1
EN2/DL12
Enable Input for Channel 2 in Manual Mode (EN2).
Delay Timer Setting for Channel 1 and Channel 2 in Sequence Mode (DL12). Connect one resistor from this pin
to ground to program the start-up and shutdown sequence delay timer for Channel 1 and Channel 2.
17
EN1/ENALL
Enable Input for Channel 1 in Manual Mode (EN1).
Grouped Enable Input for All Channels in Sequence Mode (ENALL).
Feedback Sensing Input for Channel 2.
18
FB2
19
COMP2
PVIN2
SW2
PGND2
PGND1
SW1
Error Amplifier Output for Channel 2. Connect an RC network from this pin to ground.
Power Input for Channel 2.
Switching Node Output for Channel 2.
Power Ground for Channel 2.
Power Ground for Channel 1.
20, 21
22, 23
24, 25
26, 27
28, 29
Switching Node Output for Channel 1.
Rev. A | Page 8 of 34
Data Sheet
ADP5014
Pin No.
30, 31
32
Mnemonic
Description
PVIN1
COMP1
FB1
Power Input for Channel 1.
Error Amplifier Output for Channel 1. Connect an RC network from this pin to ground.
Feedback Sensing Input for Channel 1.
33
34
AVIN
Analog Power Input for the Internal Control Circuitry. Connect a bypass capacitor between this pin and ground.
Connect a small (10 Ω) resistor between this pin and PVINx.
35
36
37
38
39
40
RT
Frequency Setting. Connect a resistor from RT to ground to program the switching frequency.
Channel 1 Reference Voltage Setting Input.
Channel 2 Reference Voltage Setting Input.
Internal Low Noise Voltage Reference Output.
Channel 3 Reference Voltage Setting Input.
VSET1
VSET2
VREF
VSET3
VSET4
Channel 4 Reference Voltage Setting Input.
Exposed Pad Analog Ground. The exposed pad must be connected and soldered to an external ground plane.
Rev. A | Page 9 of 34
ADP5014
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
100
100
90
80
70
60
50
40
30
20
10
0
90
80
70
60
50
40
30
V
V
V
V
V
V
= 1.2V FPWM
= 1.8V FPWM
= 3.3V FPWM
= 1.2V PSM
= 1.8V PSM
= 3.3V PSM
OUT
OUT
OUT
OUT
OUT
OUT
V
V
V
V
V
= 1.2V
= 1.5V
= 1.8V
= 2.5V
= 3.3V
OUT
OUT
OUT
OUT
OUT
20
10
0
0.01
0.1
1
10
0
1.0
2.0
(A)
3.0
4.0
I
(A)
I
OUT
OUT
Figure 4. Channel 1/Channel 2 Efficiency Curve, VIN = 5 V, fSW = 1.2 MHz,
FPWM Mode
Figure 7. Channel 1/Channel 2 Efficiency Curve, VIN = 5 V, fSW = 1.2 MHz,
FPWM and Automatic PWM/PSM Modes
100
90
80
70
60
50
40
30
20
100
90
80
70
60
50
40
30
V
V
V
V
V
= 1.2V
= 1.5V
= 1.8V
= 2.5V
= 3.3V
20
10
0
OUT
OUT
OUT
OUT
OUT
V
V
V
V
= 1.2V
= 1.5V
= 1.8V
= 2.5V
OUT
OUT
OUT
OUT
10
0
0
1.0
2.0
(A)
3.0
4.0
0
0.5
1.0
(A)
1.5
2.0
I
I
OUT
OUT
Figure 5. Channel 1/Channel 2 Efficiency Curve, VIN = 3.3 V, fSW = 1.2 MHz,
FPWM Mode
Figure 8. Channel 3/Channel 4 Efficiency Curve, VIN = 5 V, fSW = 1.2 MHz,
FPWM Mode
100
90
80
70
60
50
40
30
100
90
80
70
60
50
40
30
20
20
V
V
V
V
= 1.2V
= 1.5V
= 1.8V
= 2.5V
fSW = 500kHz
OUT
OUT
OUT
OUT
10
fSW = 1.2MHz
10
0
fSW = 2.4MHz
0
0
1.0
2.0
(A)
3.0
4.0
0
0.5
1.0
(A)
1.5
2.0
I
OUT
I
OUT
Figure 6. Channel 1/Channel 2 Efficiency Curve, VIN = 5 V, VOUT = 3.3 V, FPWM
Mode
Figure 9. Channel 3/Channel 4 Efficiency Curve, VIN = 3.3 V, fSW = 1.2 MHz,
FPWM Mode
Rev. A | Page 10 of 34
Data Sheet
ADP5014
100
90
80
70
60
50
40
30
20
10
1500
1400
1300
1200
1100
1000
fSW = 500kHz
fSW = 1.2MHz
fSW = 2.5MHz
0
0
–50
–20
10
40
70
100
130
0.5
1.0
(A)
1.5
2.0
TEMPERATURE (°C)
I
OUT
Figure 13. Frequency vs. Temperature, VIN = 5 V, fSW = 1.2 MHz
Figure 10. Channel 3/Channel 4 Efficiency Curve, VIN = 5 V, VOUT = 3.3 V,
FPWM Mode
6.0
5.5
5.0
4.5
4.0
3.5
3.0
100
80
60
40
V
V
V
V
V
V
= 1.2V FPWM
= 1.8V FPWM
= 3.3V FPWM
= 1.2V PSM
= 1.8V PSM
= 3.3V PSM
OUT
OUT
OUT
OUT
OUT
OUT
20
0
100
–50
0
50
0.01
0.1
1
10
TEMPERATURE (°C)
I
(A)
OUT
Figure 14. Quiescent Current vs. Temperature (Includes PVIN1, PVIN2, PVIN3,
and PVIN4)
Figure 11. Channel 3/Channel 4 Efficiency Curve, VIN = 5 V, fSW = 1.2 MHz,
FPWM and Automatic PWM/PSM Modes
90
2.010
2.005
2.000
1.995
1.990
V
V
V
= 3.3V
= 5V
IN
IN
IN
85
80
75
70
65
60
55
50
45
40
= 6V
–50
–20
10
40
70
100
130
–50
–20
10
40
70
100
130
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 15. Shutdown Current vs. Temperature (EN1/ENALL, EN2/DL12,
EN3/UV, and EN4/DL34 Low)
Figure 12. 2.0 V Reference Voltage Accuracy vs. Temperature
Rev. A | Page 11 of 34
ADP5014
Data Sheet
3.0
2.9
2.8
2.7
2.6
2.5
2.4
2.3
2.2
2.1
1
2
RISING
FALLING
2.0
–50
B
CH1 10mV
CH2 2.00V
M400ns
25.60%
A CH2
2.96V
W
–20
10
40
70
100
130
T
TEMPERATURE (°C)
Figure 19. Steady State Waveform at Heavy Load, VIN = 5 V, VOUT = 1.2 V,
Figure 16. UVLO Threshold vs. Temperature
IOUT = 3 A, fSW = 1.2 MHz, L = 0.8 µH, COUT = 47 µF × 2, FPWM Mode,
Channel 1 = VOUTX, Channel 2 = SWX
10
4A RATED
2A RATED
9
8
7
6
5
4
3
2
1
1
2
B
CH1 50mV
M100µs
25.60%
A CH2
2.96A
W
–50
–20
10
40
70
100
130
CH4 2.00A Ω
T
TEMPERATURE (°C)
Figure 20. Channel 1/Channel 2 Load Transient, 0.5 A to 3.5 A, VIN = 5 V,
VOUT = 1.2 V, fSW = 1.2 MHz, L = 0.8 µH, COUT = 47 µF × 2, Channel 1 = VOUTX
Channel 2 = IOUTX
Figure 17. Channel 1/Channel 2 Current Limit vs. Temperature
,
4
2A RATED
1A RATED
1
3
2
1
3
4
B
–50
–20
10
40
70
100
130
CH1 50mV
M 100µs
29.60%
A CH3
4.12A
W
T
CH3 2A Ω
CH4 2.00A Ω
TEMPERATURE (°C)
Figure 21. Load Transient, Channel 1/Channel 2 Parallel Output, 1 A to 6 A,
VIN = 5 V, VOUT = 1.2 V, fSW = 1.2 MHz, L = 0.8 µH, COUT = 47 µF × 4, Channel 1 = VOUT,
Channel 3 = IL1, Channel 4 = IL2
Figure 18. Channel 3/Channel 4 Current Limit vs. Temperature
Rev. A | Page 12 of 34
Data Sheet
ADP5014
1
1
2
3
2
3
4
4
B
B
B
B
B
B
B
CH1 1.00V
CH3 2.00V
CH2 2.00V
CH4 2.00V
M 4.00ms
A CH1
820mV
CH1 5.00V
CH3 5.00V
CH2 500mV
CH4 5.00A Ω
M 20.0ms
T 42.8%
A
CH2
780mV
W
W
W
W
W
W
W
W
B
T
24.20%
Figure 22. Startup for All Channels Under Sequence Enable Mode,
Channel 1 = VOUT1, Channel 2 = VOUT2, Channel 3 = VOUT3, Channel 4 = VOUT4
Figure 25. Channel 1 Shutdown with Active Output Discharge, VIN = 5 V, VOUT =
1.2 V, fSW = 1.2 MHz, L = 0.8 µH, COUT = 47 µF × 2, Channel 1 = EN1/ENALL,
Channel 2 = VOUT1, Channel 3 = PWRGD, Channel 4 = IOUT1
1
1
2
2
3
4
4
B
B
B
B
B
W
CH1 1.00V
CH3 2.00V
CH2 2.00V
CH4 2.00V
M 10.0ms
A
CH1
780mV
CH1 500mV
CH2 5.00V
CH4 5.00A Ω
M 10.0ms
25.60%
A
CH1
520mV
W
W
W
W
B
T
T
72.00%
W
Figure 23. Shutdown for All Channels Under Sequence Enable Mode,
Channel 1 = VOUT1, Channel 2 = VOUT2, Channel 3 = VOUT3, Channel 4 = VOUT4
Figure 26. Short-Circuit Protection Entry, VIN = 5 V, VOUT = 1.2 V, fSW = 1.2 MHz,
L = 0.8 µH, COUT = 47 µF × 2, Channel 1 = VOUTX, Channel 2 = SWX,
Channel 4 = ILX
1
1
2
2
3
4
4
B
B
B
B
CH1 5.00V
CH3 5.00V
CH2 500mV
M 1.00ms
A
CH2
780mV
CH1 500mV
CH2 5.00V
CH4 5.00A Ω B
M10.0ms
80.60%
A CH1
1.01V
W
W
W
W
W
CH4 5.00A Ω B
T
42.80%
W
T
Figure 24. Channel 1 Startup with Full Load, VIN = 5 V, VOUT = 1.2 V,
Channel 1 = EN1/ENALL, Channel 2 = VOUT1, Channel 3 = PWRGD,
Channel 4 = IOUT1
Figure 27. Short-Circuit Protection Recovery, VIN = 5 V, VOUT = 1.2 V, fSW = 1.2 MHz,
L = 0.8 µH, COUT = 47 µF × 2, Channel 1 = VOUTX, Channel 2 = SWX,
Channel 4 = ILX
Rev. A | Page 13 of 34
ADP5014
Data Sheet
THEORY OF OPERATION
The ADP5014 is a power management unit that combines four
high performance, low noise buck regulators in a 40-lead LFCSP
package.
operation; in PSM mode, the regulator operates with a reduced
switching frequency to maintain high efficiency. The low-side
MOSFET turns off when the output current reaches 0 A, causing
the regulator to operate in discontinuous mode (DCM).
BUCK REGULATOR OPERATIONAL MODES
Use the CFG2 pin to configure the operational mode of all four
buck regulators to operate in PWM mode or automatic
PWM/PSM mode.
PWM Mode
In PWM mode, the buck regulators in the ADP5014 operate at
a fixed frequency; this frequency is set by an internal oscillator
that is programmed by the RT pin. At the start of each
oscillator cycle, the high-side MOSFET switch turns on and sends
a positive voltage across the inductor. The inductor current
increases until the current sense signal exceeds the peak
inductor current threshold that turns off the high-side
MOSFET switch. This threshold is set by the error amplifier
output. During the high-side MOSFET off time, the inductor
current decreases through the low-side MOSFET switch until
the next oscillator clock pulse starts a new cycle. The buck
regulators in the ADP5014 regulate the output voltage by
adjusting the peak inductor current threshold.
LOW NOISE ARCHITECTURE
Traditional dc-to-dc or linear regulator output noise is typically
proportional to the output voltage setting. The ADP5014 optimizes
many analog blocks to achieve lower output noise at low frequency
range. The unity-gain voltage reference structure also makes its
output noise independent from the output voltage setting when
VOUT setting is less than VREF voltage.
The low noise buck regulator enables the device to power up noise
sensitive signal chain products directly with excellent output noise
performance, ~25 μV rms from 10 Hz to 100 kHz, which is similar
or even better than traditional low dropout regulators (LDOs).
PSM Mode
The additional LC filter is still required because the fundamental
switching output ripple and its harmonic affects signal chain
performance and likely generates unexpected spurs. This
additional LC filter is typically relatively small due to the high
switching frequency operation of the buck regulator in the
ADP5014.
To achieve higher efficiency, the buck regulators in the
ADP5014 smoothly transition to variable frequency PSM mode
operation when the output load falls below the PSM current
threshold. When the output voltage falls below regulation, the
buck regulator enters PWM mode for a few oscillator cycles
until the voltage increases to within regulation. During the idle
time between bursts, the MOSFET switch turns off, and the
output capacitor supplies all the output current.
INTERNAL REFERENCE (VREF)
The ADP5014 provides an accurate, low noise, 2.0 V reference
voltage. One 0.47 μF ceramic capacitor must be connected
between VREF and ground. A larger value of capacitance provides
better noise suppression.
The PSM mode comparator monitors the internal compensation
node, which represents the peak inductor current information.
The average PSM mode current threshold depends on the input
voltage (VIN), the output voltage (VOUT), the inductor, and the
output capacitor. Because the output voltage occasionally falls
below regulation and then recovers, the output voltage ripple in
PSM mode is larger than the ripple in the forced PWM mode of
operation under light load conditions.
The VREF reference circuitry is mainly designed for internal use
and has very limited output load capacity (<1 mA); therefore,
check the load capability requirements if VREF is used for other
purposes.
ADJUSTABLE OUTPUT VOLTAGE
The ADP5014 provides adjustable output voltage settings via
the external resistor divider. To minimize output noise and
maintain the loop unity-gain, the device provides the reference
input path to the error amplifier input with the integrated low-
frequency filter for each channel. Use an external resistor
divider to set the desired output voltage. Figure 28 shows the
adjustable output voltage diagram.
FPWM and Automatic PWM/PSM Modes
The buck regulators can be configured to always operate in FPWM
mode using the CFG2 configuration pin. In forced PWM mode,
the regulator continues to operate at a fixed frequency even when
the output current is below the PWM/PSM threshold. In PWM
mode, the efficiency is lower compared to PSM mode under light
load conditions. The low-side MOSFET remains on when the
inductor current falls to less than 0 A, causing the ADP5014 to
enter continuous conduction mode (CCM).
PVINx
SWx
VOUTx
COUTx
VREF
BUCK
VFBx
The buck regulators can be configured to operate in automatic
PWM or PSM mode using the CFG2 configuration pin. In
automatic PWM/PSM mode, the buck regulators operate in
either PWM mode or PSM mode, depending on the output
current. When the average output current falls below the
PWM/PSM threshold, the buck regulator enters PSM mode
R
R
A
R
TOP
VSETx
B
R
BOT
Figure 28. Adjustable Output Voltage Configuration
Rev. A | Page 14 of 34
Data Sheet
ADP5014
FUNCTION CONFIGURATIONS (CFG1 AND CFG2)
The CFG2 pin can be used to program the operation mode
(FPWM or PWM/PSM mode), the enable mode (manual mode
or sequence mode), the timer (×1 or ×8), and GPIO
functionalities (PWRGD, SYNC-IN, CLK-OUT, UVO) for all
channels. Table 7 provides the values of the resistors needed to
set different functionality in the CFG2 pin.
The ADP5014 include CFG1 and CFG2 pins to decode the
function configurations for all channels. The CFG1 pin has a
logic status of 8 that is decoded by connecting one resistor to
ground, whereas the CFG2 pin has a logic status of 16, decoded by
connecting one resistor to ground. This decoder circuitry only
works in the initiation stage of the ADP5014; therefore, the
configurations cannot be changed in operation. Typically, the
chip initiation takes less than 1 ms before the enabled regulator
starts switching.
The RCFG1 and RCFG2 resistors must have 1% tolerance to ensure
the correct decoding result.
Table 7. Configuration by the CFG2 Pin
The CFG1 pin can be used to program the load output capability
and parallel operation for all channels. Table 6 provides the
values of the resistors needed to set different functionality in the
CFG1 pin.
RCFG2
(kΩ)
0
Enable
Mode
Operation
Timer Mode
GPIO
Manual
×1
×1
×1
×1
×8
×8
×8
×8
×1
×1
×1
×1
×8
×8
×8
×8
FPWM
FPWM
FPWM
PSM
PWRGD
SYNC-IN
CLK-OUT
PWRGD
PWRGD
SYNC-IN
CLK-OUT
PWRGD
UVO
10
Manual
12.1
14.7
Float
17.8
21.5
26.1
31.6
38.3
46.4
56.2
68.1
82.5
100
121
Manual
Table 6. Configuration by the CFG1 Pin
Output Capability
Manual
Manual
FPWM
FPWM
FPWM
PSM
RCFG1 (kΩ) Channel 1 Channel 2 Channel3 Channel 4
Manual
0
4 A
4 A
2 A
2 A
2 A
2 A
2 A
2 A
1 A
2 A
1 A
2 A
2 A
1 A
2 A
1 A
2 A
Manual
10
4 A
Manual
12.1
14.7
17.8
21.5
26.1
31.6
4 A
Sequence
Sequence
Sequence
Sequence
Sequence
Sequence
Sequence
Sequence
FPWM
FPWM
FPWM
PSM
2 A
SYNC-IN
CLK-OUT
UVO
2 A
Parallel 8A
4 A
Parallel 8 A 2 A
4 A
Parallel 4 A Parallel 4 A
FPWM
FPWM
FPWM
PSM
UVO
Parallel 8 A Parallel 8 A Parallel 4 A Parallel 4 A
SYNC-IN
CLK-OUT
UVO
Rev. A | Page 15 of 34
ADP5014
Data Sheet
CHANNEL 1 CURRENT
CHANNEL 2 CURRENT
PARALLEL OPERATION
The ADP5014 supports 2-phase parallel operation of Channel 1
and Channel 2 to provide a single output with up to 8 A of
current, and two-phase parallel operation of Channel 3 and
Channel 4 to provide a single output with up to 4 A of current.
To configure a 2-phase single output in parallel operation,
perform the following steps (see Figure 29). Use the CFG1 pin
to select parallel operation as specified in Table 7.
Leave the COMP2 pin (or COMP4 pin) open.
Use the VSET1 and FB1 pin (or VSET3 and FB3 pin) to set
the output voltage.
0
2
4
6
8
Connect the FB2 and VSET2 pin (or FB4 pin and VSET4)
to ground (FB2 is ignored). Connect the EN2/DL12 pin (or
EN4/DL34 pin) to ground in manual enable mode (EN2 is
ignored). Note that the EN2/DL12 pin is for the delay timer
configuration in sequence enable mode.
TOTAL OUTPUT LOAD (A)
Figure 30. Current Balance in Parallel Output Configuration, VIN = 5 V,
VOUT = 1.2 V, fSW = 1.2 MHz, FPWM Mode
MANUAL/SEQUENCE MODE
The ADP5014 features two enable modes using the CFG2 pin
configuration. The manual mode has individual precision
enable pins to enable each regulator manually. Alternatively,
the sequence mode has one grouped precision enable signal
with a programmable power-up and power-down delay timer on
each rail.
PVIN1
VIN
VOUT
(UP TO 8A)
PVIN2
CFG1
L1
SW1
FB1
CH1
BUCK
(4A)
VREF
VSET1
The enable pin (EN1 to EN4) functionality is different in
manual mode and sequence mode. Note that throughout this
data sheet, multifunction pins, such as EN1/ENALL, are referred to
by either the entire pin name or by a single function of the pin, for
example, EN1, when only that format is relevant. Figure 31 and
Table 8 show the pin mapping in different enable modes.
CH2
BUCK
(4A)
VSET2
L2
SW2
FB2
COMP1
COMP2
EN1
EN2
Figure 29. Parallel Operation for Channel 1 and Channel 2
If some channels are unused, pull down the corresponding
PVINx and ENx pin to ground and leave the SWx, COMPx,
VSETx, and FBx pins floating.
The following considerations apply when two channels are
operating in the parallel configuration:
MANUAL ENABLE
SEQUENCE ENABLE
MODE
MODE
The input voltages for both channels are the same.
Both channels are operating in forced PWM mode.
Do not support sequence mode.
VOUT1 ENALL
VOUT1
VOUT2
VOUT3
EN1
EN2
EN3
EN4
CHANNEL 1
CHANNEL 2
CHANNEL 3
CHANNEL 1
CHANNEL 2
CHANNEL 3
CHANNEL 4
DL12
VOUT2
The current balance in parallel configuration is well regulated
by the internal control loop. Figure 30 shows the typical current
balance matching in the parallel output configuration.
VOUT3
DL34
VOUT4
GPIO
VOUT4
CHANNEL 4
+
UV
GPIO
0.6V
–
Figure 31. Pin Configuration in Different Enable Modes
Table 8. Pin Functionality in Different Enable Modes
Pin Name
Manual Enable Mode
Sequence Enable Mode
EN1/ENALL (Pin 17)
EN2/DL12 (Pin 16)
EN3/UV (Pin 13)
EN4/DL34 (Pin 12)
EN1—enable pin for Channel 1
EN2—enable pin for Channel 2
EN3—enable pin for Channel 3
EN4—enable pin for Channel 4
ENALL—grouped enable pin for all four channels
DL12—delay timer setting for Channel 1 and Channel 2
UV—undervoltage comparator input
DL34—delay timer setting for Channel 3 and Channel 4
Rev. A | Page 16 of 34
Data Sheet
ADP5014
Manual Mode (Precision Enable)
Sequence Mode
In manual mode, the ADP5014 has an individual precision
enable pin for each regulator. The enable control pin (ENx)
features a precision enable circuit with a 0.6 V reference
voltage. When the voltage at the ENx pin is greater than 0.6 V
(typical), the regulator is enabled. When the ENx pin voltage
falls below 0.57 V (typical), the regulator is disabled. To force
the regulator to automatically start up when input power is
applied, connect the enable pin to the input.
In sequence mode, all channels in the ADP5014 turn on and off
under the control of the internal sequencer, which is triggered
by the ENALL pin. The DL12 and DL34 pins set the predefined
delay timer.
The ENALL pin features precision enable circuitry with a 0.6 V
turn on threshold and internal pull-down current source.
When the ENALL pin goes above the 0.6 V precision threshold,
all channels controlled by the sequencer begin a soft start after
the delay time specified by the DL12 and DL34 pin configuration.
Similarly, when the ENALL pin falls below 0.57 V precision
threshold, the channels turns off after the delay time specified
by DL12 and DL34 pin configurations.
The precision enable pin has an internal pull-down current
source (4 μA) that provides a default turn off when the enable
pin is left open. When the enable pin exceeds 0.6 V (typical),
the regulator is enabled and the internal pull-down current
source at the enable pin decreases to 1 μA. The decrease in the
current source allows the ratio of the external resistor divider to
program the UVLO threshold to monitor either the input
voltage or the output voltage while using the absolute value of
external resistor divider to program the hysteresis window.
Figure 32 shows the precision enable diagram.
Figure 33 shows the logical states of each channel and does not
show soft start and discharge ramps. Although the output
discharge switch helps to discharge the output capacitor quickly,
the discharge ramps on the output of each channel are still
decided by many different factors, including the output
capacitance, system load, and the ramps of input supply.
DL12 configures the delay timer for Channel 1 and Channel 2 by
connecting one resistor to ground. Similarly, DL34 configures the
delay timer for Channel 3 and Channel 4 (see Table 9). In parallel
operation, the slave channel (Channel 2 or Channel 4) always
follows up with the delay timer configuration of the master
channel; therefore, Channel 2 follows Channel 1, while Channel 4
follows Channel 3. The delay timer decoder circuitry only works
in the initiation stage of the ADP5014; therefore, the delay
timer does not change in operation.
R
TOP_EN
EN_CMP
+
0.6V
–
R
BOT_EN
1µA
3µA
Figure 32. Precision Enable Diagram for One Channel
ENALL
tDIS_DLY1
tDIS_DLY2
tDIS_DLY3
tDIS_DLY4
tEN_DLY1
ON
ON
ON
ON
CHANNEL1
CHANNEL2
OFF
OFF
OFF
OFF
tEN_DLY2
tEN_DLY3
tEN_DLY4
CHANNEL3
CHANNEL4
Figure 33. Power-Up/Power-Down in Sequence Enable Mode
Rev. A | Page 17 of 34
ADP5014
Data Sheet
Table 10. Power-Up and Power-Down Timer
Table 9. Setting Sequence Timer in the DL12 and DL34 Pins
Sequence
Order
Power-Up Delay Timer
Power-Down Delay
Timer (tDIS_DLYx
RDL12
(or RDL34
(kΩ)
(tEN_DLYx
)
)
)
Channel 1 Sequence
(or Channel 3)
Channel 2 Sequence
(or Channel 4)
First Order
0 ms
36 ms (288 ms at
×8 option)
10
First order
First order
Second
Order
Third Order
6 ms (48 ms at ×8 option)
24 ms (192 ms at
×8 option)
12 ms (96 ms at
×8 option)
0
First order
First order
First order
Second order
Third order
Fourth order
First order
Second order
Third order
Fourth order
First order
Second order
Third order
Fourth order
First order
Second order
Third order
Fourth order
12.1
14.7
17.8
21.5
26.1
31.6
38.3
46.4
56.2
Float
68.1
82.5
100
121
12 ms (96 ms at ×8
option)
18 ms (144 ms at ×8
option)
Second order
Second order
Second order
Second order
Third order
Third order
Third order
Third order
Fourth order
Fourth order
Fourth order
Fourth order
Fourth
Order
0 ms
GENERAL PURPOSE INPUT/OUTPUT (GPIO)
The ADP5014 includes one GPIO pin which can be configured
for different functionalities, such as PWRGD, synchronization
clock input (SYNC-IN), CLK-OUT, or UVO.
The PWRGD and UVO output functionalities have the open-
drain output after the initiation.
The CLK-OUT output functionality features a push/pull output,
enabling it to drive other regulators after initiation.
OSCILLATOR
Note that the RDL12 and RDL34 resistors must have 1 % tolerance
to ensure the correct decoding result.
The switching frequency (fSW) of the ADP5014 can be set to a
value from 500 kHz to 2.5 MHz by connecting a resistor from
the RT pin to ground. Calculate the value of the RT resistor
(RRT) as follows:
The power-up and power-down delay timer for all channels is
designed in an opposite manner to meet typical system
sequence requirements, as described below:
R
RT (kΩ) = 100,000/fSW (kHz)
•
•
•
•
First order sequence means the channel is configured as
the first to be powered up, and is shut down last.
Figure 34 shows the typical relationship between fSW and the RT
resistor. The adjustable frequency allows users to make decisions
based on the trade-off between efficiency and the size of the
solution.
Second order sequence means the channel is configured as
the second to be powered up and is shut down third.
Third order sequence means the channel is configured as
the third to be powered up and is shut down second.
Fourth order sequence means the channel is configured as
the fourth to be powered up and is shut down first.
2700
2400
2100
1800
1500
1200
900
If a longer sequence timer is required, the delay time for all
channels can be increased by 8 times (×8 option) using the
CFG2 pin. Table 10 shows the power-up and power-down timer
configurations.
In sequence enable mode, the device performs the following
actions in fault conditions:
600
•
During individual fault conditions, such as overcurrent
hiccup, OVP, or PVINx, UVLO shuts down and powers up
the corresponding channel immediately without the
sequence delay.
300
20
60
100
140
180
220
RT RESISTOR (kΩ)
Figure 34. Switching Frequency vs. RT Resistor
•
•
TSD fault shuts down all channels immediately without the
sequence delay, but occurs after the defined power-up
sequence for the recovery.
An AVIN UVLO fault shuts down all channels immediately
without any sequence delay, but occurs after the defined
power-up sequence for the recovery after the device
reinitiation.
Rev. A | Page 18 of 34
Data Sheet
ADP5014
Phase Shift
POWER-GOOD FUNCTION
By default, the phase shift between Channel 1 and Channel 2 and
between Channel 3 and Channel 4 is 180° (see Figure 35). This
value provides the benefits of out of phase operation by reducing
the input ripple current and lowering the grounding noise.
The ADP5014 GPIO pin can be configured as an open-drain
power-good output (PWRGD pin) that becomes active high
when the selected buck regulators are operating normally.
A high status in the PWRGD pin indicates that the regulated
output voltage of the buck regulator is above 90% (typical) of its
nominal output. When the regulated output voltage of the buck
regulator falls below 87% (typical) of its nominal output for a
delay time greater than approximately 50 µs, the status of the
PWRGD pin is set to low.
0° REFERENCE
CH 1
180° PHASE SHIFT
CH 2
0° REFERENCE
The output of the PWRGD pin is the logical AND of the internal
PWRGD signals on an individual channel. An internal PWRGD
signal on an individual channel must be high for a validation
time of 2 ms (typical) timer before the PWRGD pin goes high.
This validation timer can be increased by 8 times (×8 option)
using the CFG2 pin configuration; if one internal PWRGD fails,
the PWRGD pin goes low with no delay.
CH 3
180° PHASE SHIFT
CH 4
Figure 35. Phase Shift Diagram, Four Buck Regulators
SYNCHRONIZATION INPUT/OUTPUT
The GPIO pin can be configured as the synchronization clock
input by using the CFG2 pin (see Table 7), and the switching
frequency of the ADP5014 can be synchronized to an external
clock with a frequency range from 500 kHz to 2.5 MHz. The
ADP5014 automatically detects the presence of an external
clock applied to the GPIO pin, and the switching frequency
transitions smoothly to the frequency of the external clock.
When the external clock signal stops, the device automatically
switches back to the internal clock and continues to operate.
UV COMPARATOR (SEQUENCE MODE ONLY)
In sequence mode, the EN3/UV pin is used as the UVO input
(UV pin), while the ADP5014 GPIO pin can be configured as
an open-drain UVO via CFG2 pin configuration. The UV
comparator is not related to the channel enabling and is only
used for monitoring purposes. For example, it can be used to
monitor any output voltage to create a power-good signal in
sequence mode.
Similar to the precision enable functionality, this UVO features
the same precise 0.6 V reference voltage with the 1 µA or 4 µA
pull-down hysteresis current. Using the ratio of external resistor
divider to program the UVLO threshold allows monitoring
either input voltage or output voltage while using the absolute
value of the external resistor divider to program the hysteresis
window. The UV pin is connected to the input supply if it is not
intended for use. Figure 37 shows the UVO diagram.
The internal switching frequency set by the RT pin must be
programmed to a value that is close to the external clock value
for successful synchronization; the suggested frequency
difference is less than 15% in typical applications.
The GPIO pin can be configured as a push/pull synchronization
clock output by CFG2 (refer to Table 7). A positive clock pulse
with a 50% duty cycle is generated at the GPIO pin with a
frequency equal to the internal switching frequency set by the
RT pin.
PVIN
Figure 36 shows two ADP5014 devices configured for frequency
synchronization mode: one ADP5014 device is configured as
the clock output to synchronize another ADP5014 device.
R
TOP
UV
(CLOCK MASTER)
(SLAVE)
+
UVO
0.6V
–
GPIO
GPIO
(CLK-OUT) (SYNC-IN)
R
BOT
1µA
3µA
CFG2
CFG
R1
R2
ADP5014
DEVICE 1
ADP5014
DEVICE 2
Figure 37. Undervoltage Comparator Diagram (in Sequence Mode Only)
Figure 36. Two ADP5014 Devices Configured for Synchronization Mode
In the configuration shown in Figure 36, the phase shift
between Channel 1 of the first ADP5014 device and Channel 1
of the second ADP5014 device is 0˚.
Rev. A | Page 19 of 34
ADP5014
Data Sheet
SOFT START
SHORT-CIRCUIT PROTECTION (SCP)
The buck regulators in the ADP5014 include soft start circuitry
that ramps the output voltage in a controlled manner during
startup, thereby limiting the inrush current. The soft start time
for all channels is typically fixed at 2 ms. The soft start time for
all channels can be increased by eight times using the CFG2 pin
configuration.
The buck regulators in the ADP5014 include a hiccup mode for
OCP. When the peak inductor current reaches the current-limit
threshold, the high-side MOSFET turns off and the low-side
MOSFET turns on until the next cycle.
When hiccup mode is active, the overcurrent fault counter is
incremented. If the overcurrent fault counter reaches 15 and
overflows (indicating a short-circuit condition), both the high-side
and low-side MOSFETs are turned off. The buck regulator
remains in hiccup mode for a period equal to seven soft start
cycles and then attempts to restart from soft start. If the short-
circuit fault has cleared, the regulator resumes normal operation;
otherwise, it reenters hiccup mode after the soft start.
STARTUP WITH PRECHARGED OUTPUT
The buck regulators in the ADP5014 include a precharged
startup feature to protect the low-side FETs from damage
during startup. If the output voltage is precharged before the
regulator is turned on, the regulator prevents reverse inductor
current, which discharges the output capacitor, until the
internal soft start reference voltage exceeds the precharged
voltage on a feedback (FBx) pin.
Hiccup detection is masked during the initial soft start cycle to
enable startup of the buck regulator under heavy load conditions.
Careful design and proper component selection are required to
ensure the buck regulator recovers from hiccup mode under
heavy loads.
CURRENT-LIMIT PROTECTION
The buck regulators in the ADP5014 include peak current-limit
protection circuitry to limit the amount of positive current
flowing through the high-side MOSFET switch. The peak
current limit on the power switch limits the amount of current
that can flow from the input to the output. The programmable
current-limit threshold feature allows the use of small size
inductors for low current applications.
In parallel operation, the overcurrent protection in either
channel triggers both master and slave channels entering and
exiting the hiccup protection together.
OVERVOLTAGE PROTECTION
The ADP5014 includes an overvoltage protection feature to
protect the regulator against an output short to a higher voltage
supply, or when a strong load disconnect transient occurs. If the
feedback voltage increases to 1.15 × VSETx, the internal high-
side and low-side MOSFETs are turned off until the voltage at
the FBx pin decreases to 1.1 × VSETx At that time, the
ADP5014 resumes normal operation.
To configure different output load capability, connect a resistor
from the CFG1 pin to ground according to Table 6 which lists
different output current capability settings for all channels.
The buck regulators in the ADP5014 include negative current-
limit protection circuitry to limit certain amounts of negative
current flowing through the low-side MOSFET switch.
UNDERVOLTAGE LOCKOUT
FREQUENCY FOLD BACK
UVLO circuitry monitors the input voltage level of each buck
regulator, including the analog input pin in the ADP5014. If
any input voltage (PVINx pin) falls below 2.40 V (typical), the
corresponding channel is turned off. After the input voltage rises
above 2.65 V (typical), the soft start period is initiated, and the
corresponding channel is enabled when the ENx pin is high.
The buck regulators in the ADP5014 include frequency fold
back to prevent output current runaway when a hard short
occurs on the output. Frequency fold back is implemented as
follows:
•
If the voltage at the FBx pin falls below half of the target
output voltage, the switching frequency is reduced by half.
If the voltage at the FBx pin falls again to below one-fourth
of the target output voltage, the switching frequency is
reduced by half of its current value again, equaling one-
fourth of fSW.
A UVLO condition on the AVIN pin has a higher priority than
a UVLO condition on individual channels, which means the
AVIN pin supply must be available before individual channels
can be operated.
•
The ADP5014 supports separate input voltages for buck
regulators. This means that the input voltages for each
individual buck regulator can be connected to different supply
voltages, as long as its input voltage (PVINx pin) and its AVIN pin
voltage are above its UVLO threshold.
The reduced switching frequency allows more time for the
inductor current to decrease, but also increases the ripple
current during peak current regulation. The reduced switching
frequency results in a reduction in average current and prevents
output current runaway.
Rev. A | Page 20 of 34
Data Sheet
ADP5014
ACTIVE OUTPUT DISCHARGE SWITCH
THERMAL SHUTDOWN
Each buck regulator in the ADP5014 integrates a discharge
switch from the switching node to ground. This switch is turned on
when its associated regulator is disabled, which helps discharge
the output capacitor quickly. The typical value of the discharge
switch is 85 Ω for Channel 1 to Channel 4.
If the ADP5014 junction temperature exceeds 150°C, the thermal
shutdown circuit turns off the IC except for the internal linear
regulator. Extreme junction temperatures can be the result of
high current operation, poor circuit board design, or high ambient
temperature. A 15°C hysteresis is included so that the ADP5014
does not return to operation after thermal shutdown until the
on-chip temperature falls below 135°C. When the device exits
thermal shutdown, a soft start is initiated for each enabled channel.
Rev. A | Page 21 of 34
ADP5014
Data Sheet
APPLICATIONS INFORMATION
The equation for the output voltage setting is as follows:
ADIsimPOWER DESIGN TOOL
V
OUT = VREF × (1 + (RTOP/RBOT))
The ADP5014 is supported by the ADIsimPower™ design tool
set. ADIsimPower is a collection of tools that produce complete
power designs optimized for a specific design goal. The tools
enable the user to generate a full schematic and bill of materials
and to calculate performance in minutes. ADIsimPower can
optimize designs for cost, area, efficiency, and device count
while considering the operating conditions and limitations of the
IC and all real external components. The ADIsimPower tool can
be found at http://www.analog.com/ADIsimPower; the user
can request an unpopulated board through the tool.
where:
V
V
R
R
OUT is the output voltage.
REF is the 2.0 V accurate low noise reference voltage.
TOP is the feedback resistor from VOUT to FB.
BOT is the feedback resistor from FB to ground.
VOLTAGE CONVERSION LIMITATIONS
For a given input voltage, lower limitations on the output voltage
exist due to the minimum on time and the minimum off time.
The minimum output voltage for a given input voltage and
switching frequency is limited by the minimum on time. The
minimum on time for each channel is 60 ns (typical). The
minimum on time increases at higher junction temperatures.
PROGRAMMING THE OUTPUT VOLTAGE
The output voltage of the ADP5014 is externally set by a resistive
voltage divider from the VREF pin to the VSETx pin and a
resistive voltage divider from the output voltage to the FBx pin.
To limit the degradation of the output voltage accuracy due to
VSETx and FBx bias current, ensure the value of the bottom
resistor in the dividers is not too large.
Note that in FPWM mode, the output voltage potentially
exceeds the nominal output voltage when the minimum on
time limit is reached. Careful switching frequency selection is
required to avoid this problem.
The ADP5014 provides adjustable output voltage settings. Use
the resistor divider from the accurate internal VREF reference
voltage (VREF pin) to set the desired output voltage and
directly tie the FBx pin to the output when the desired output
voltage setting is less than the VREF voltage, as shown in Figure 38.
The equation for the output voltage setting is
The minimum output voltage in CCM mode for a given input
voltage and switching frequency is calculated using the
following equation:
V
OUT_MIN = VIN × tMIN_ON × fSW − (RDSON1 − RDSON2) ×
OUT_MIN × tMIN_ON × fSW − (RDSON2 + RL) × IOUT_MIN
where:
OUT_MIN is the minimum output voltage.
MIN_ON is the minimum on time.
SW is the switching frequency.
I
(1)
V
OUT = VREF × (R2/(R1+R2))
V
t
f
where:
V
V
OUT is the output voltage.
REF is the 2.0 V accurate low noise reference voltage.
R
R
DSON1 is the high-side MOSFET on resistance.
DSON2 is the low-side MOSFET on resistance.
R2 is the resistor from VSETx to ground.
R1 is the resistor from VSETx to VREF
.
I
OUT_MIN is the minimum output current.
If the desired output voltage exceeds the VREF voltage, use an
external resistor divider from the output to the FBx pin to set
the desired output voltage, and tie VSETx to VREF directly, as
shown in Figure 39.
RL is the resistance of the output inductor.
VREF
ADP5014
INTERNAL
REFERENCE 2.0V
R1
VSETx
FBx
R2
COMPx
+
L
VOUTx
C
SWx
EA
–
Figure 38. Configure the Output Voltage when VOUTx ≤ VREF
VREF
ADP5014
INTERNAL
REFERENCE 2.0V
L
VOUTx
C
SWx
FBx
VSETx
R
TOP
+
EA
–
COMPx
R
BOT
Figure 39. Configure the Output Voltage when VOUTX > VREF
Rev. A | Page 22 of 34
Data Sheet
ADP5014
The maximum output voltage for a given input voltage and
switching frequency is limited by the minimum off time or the
maximum duty cycle. The minimum off time for each channel
is 50 ns (typical).
INDUCTOR SELECTION
The inductor value is determined by the operating frequency,
input voltage, output voltage, and inductor ripple current. Using
a small inductor yields faster transient response but degrades
efficiency due to the larger inductor ripple current. Using a large
inductor value yields a smaller ripple current and better efficiency,
but results in slower transient response. Therefore, a trade-off
must be made between the transient response and efficiency. As
a guideline, the inductor ripple current, ΔIL, is typically set to a
value from 30% to 40% of the maximum load current. The
inductor value is calculated using the following equation:
The maximum output voltage for a given input voltage and
switching frequency is calculated using the following equation:
V
OUT_MAX = VIN × (1 − tMIN_OFF × fSW) − (RDSON1 − RDSON2) ×
OUT_MAX × (1 − tMIN_OFF × fSW) − (RDSON2 + RL) × IOUT_MAX (2)
where:
OUT_MAX is the maximum output voltage.
MIN_OFF is the minimum off time.
SW is the switching frequency.
I
V
t
f
L = [(VIN − VOUT) × D]/(ΔIL × fSW)
R
DSON1 is the high-side MOSFET on resistance.
where:
R
DSON2 is the low-side MOSFET on resistance.
VIN is the input voltage.
I
OUT_MAX is the maximum output current.
V
OUT is the output voltage.
RL is the resistance of the output inductor.
D is the duty cycle (D = VOUT/VIN).
ΔIL is the inductor ripple current.
As shown in Equation 1 and Equation 2, reducing the switching
frequency eases the minimum on time and off time limitations.
f
SW is the switching frequency.
The ADP5014 has internal slope compensation in the current
loop to prevent subharmonic oscillations when the duty cycle is
greater than 50%.The inductor peak current is calculated using
the following equation:
CURRENT-LIMIT SETTING
The ADP5014 has two selectable current-limit thresholds for
each channel. Ensure that the selected current-limit value is
larger than the peak current of the inductor, IPEAK. See Table 6
for the current-limit configuration for each channel.
I
PEAK = IOUT + (ΔIL/2)
The saturation current of the inductor must be larger than the
peak inductor current. For ferrite core inductors with a fast
saturation characteristic, the saturation current rating of the
inductor are higher than the current-limit threshold of the buck
regulator to prevent the inductor from becoming saturated.
SOFT START SETTING
The buck regulators in the ADP5014 include soft start circuitry
that ramps the output voltage in a controlled manner during
startup, thereby limiting the inrush current. To set the soft start
time to a value of 2 ms or 16 ms, connect a resistor from the
CFG2 pin to the ground (see the Soft Start section).
The rms current of the inductor is calculated using the
following equation:
2
∆IL
12
2
IRMS
=
IOUT
+
Shielded ferrite core materials are recommended for low core
loss and low electromagnetic interference (EMI). Table 11 lists
the recommended inductors.
Table 11. Recommended Inductors
Vendor
Part No.
Value (µH)
0.6
1.0
1.5
2.2
ISAT (A)
10.4
8.7
7.1
5.6
IRMS (A)
11.7
9.6
7.5
5.5
DCR (mΩ)
9.5
13.3
21.5
35.2
30
35
50
70
Size (mm)
4 × 4
4 × 4
4 × 4
4 × 4
Coilcraft
XAL4020-601
XAL4020-102
XAL4020-152
XAL4020-222
TOKO
Wurth
DFE252012P-R68M
DFE252012P-1R0P
DFE252012P-1R5P
DFE252012P-2R2P
744383560068
74438356010
74438356015
74438356022
0.68
1.0
1.5
5.3
4.8
3.9
3.4
4.1
3.8
3.0
2.6
2.5 × 2.0
2.5 × 2.0
2.5 × 2.0
2.5 × 2.0
4.1 × 4.1
4.1 × 4.1
4.1 × 4.1
4.1 × 4.1
2.2
0.68
1
1.5
9.4
9.0
7.8
6.2
8.2
7.2
5.8
4.7
7.5
12
15
29
2.2
Rev. A | Page 23 of 34
ADP5014
Data Sheet
INPUT CAPACITOR SELECTION
OUTPUT CAPACITOR SELECTION
The input decoupling capacitor attenuates high frequency noise
on the input and acts as an energy reservoir. This capacitor is a
ceramic capacitor and must be placed close to the PVINx pins.
The loop composed of the input capacitor, the high-side MOSFET,
and the low-side MOSFET must be kept as small as possible.
The voltage rating of the input capacitor must be greater than
the maximum input voltage. The rms current rating of the
input capacitor (ICIN_rms)is larger than the following equation:
The selected output capacitor affects both the output voltage
ripple and the loop dynamics of the regulator. For example, during
load step transients on the output, when the load is suddenly
increased, the output capacitor supplies the load until the
control loop can ramp up the inductor current, causing an
undershoot of the output voltage.
The output capacitance required to meet the voltage droop
requirement (COUT_UV) is calculated using the following equation:
ICIN_rms = IOUT ×
D (1 D)
KUV ISTEP 2 L
COUT _UV
where D is the duty cycle (D = VOUT/VIN).
2
VIN VOUT VOUT _UV
PROGRAMMING THE UVLO INPUT
where:
UV is a factor (typically set to 2).
ΔISTEP is the load step.
K
The precision enable input can be used to program the UVLO
threshold of the input voltage, as shown in Figure 32.
ΔVOUT_UV is the allowable undershoot on the output voltage.
The precision turn on threshold is 0.6 V. Use the following
Another example of the effect of the output capacitor on the loop
dynamics of the regulator is when the load is suddenly removed
from the output. The energy stored in the inductor rushes into
the output capacitor, causing an overshoot of the output voltage.
equations to calculate RTOP_EN and RBOT_EN
TOP_EN = (0.57 V × VIN_RISING − 0.6 × VIN_FALLING)/(0.57 V ×
4 μA − 0.6 × 1 μA)
BOT_EN = (0.6 V × RTOP_EN)/(VIN_RISING – RTOP_EN × 4 μA − 0.6 V)
where:
TOP_EN is the resistor from PVINx to ENx.
:
R
R
The output capacitance required to meet the overshoot
requirement (COUT_UV) is calculated using the following equation:
R
KOV ISTEP 2 L
V
IN_RISING is the VIN rising threshold.
COUT _OV
2
2
VOUT VOUT_OV
VOUT
V
IN_FALLING is the VIN falling threshold.
R
BOT_EN is the resistor from ENx to ground.
where:
OV is a factor (typically set to 2).
ΔISTEP is the load step.
K
COMPENSATION COMPONENTS DESIGN
For the peak current-mode control architecture, the power stage
can be simplified as a voltage controlled current source that
supplies current to the output capacitor and load resistor. The
simplified loop is composed of one domain pole and a zero
contributed by the ESR of the output capacitor. The control to
output transfer function (Gvd) is shown in the following equations:
ΔVOUT_OV is the allowable overshoot on the output voltage.
The output voltage ripple is determined by the equivalent series
resistance (ESR) of the output capacitor and its capacitance
value. Use the following equation to select a capacitor that can
meet the output ripple requirements:
IL
s
COUT _ RIPPLE
1
1
8 fSW VOUT _ RIPPLE
2 fz
V
OUT (s)
G
vd (s)
AVI R
VCOMP (s)
VOUT _ RIPPLE
s
RESR
2 f p
IL
where:
ΔVOUT_RIPPLE is the allowable output voltage ripple.
ESR is the ESR of the output capacitor.
1
fz
2RESR COUT
R
1
Select the largest output capacitance given by COUT_UV, COUT_OV
and COUT_RIPPLE to meet both load transient and output ripple
requirements.
,
fp
2
RRESR COUT
where:
The selected output capacitor voltage rating must be greater
than the output voltage. The minimum rms current rating of
the output capacitor (ICOUT_rms) is determined by the following
equation:
AVI = 16.67A/V for Channel 1 or Channel 2, and 8.33 A/V for
Channel 3 or Channel 4.
R is the load resistance.
fz is the frequency of the zero.
C
R
OUT is the output capacitance.
ESR is the equivalent series resistance of the output capacitor.
fp is the frequency of the pole.
IL
12
ICOUT_rms
=
Rev. A | Page 24 of 34
Data Sheet
ADP5014
The ADP5014 uses a transconductance amplifier as the error
amplifier to compensate the system. Figure 40 shows the
simplified peak current-mode control small signal circuit.
Power Switch Conduction Loss (PCOND
)
Power switch conduction losses are caused by the flow of output
current through both the high-side and low-side power switches,
each of which has on resistance (RDS(ON).
V
V
OUT
OUT
R
TOP
Use the following equation to estimate the power switch
conduction loss:
V
C
R
COMP
OUT
–
gm
+
+
–
A
VI
2
P
COND = (RDS(ON)_HS × D + RDS(ON)_LS × (1 − D)) × IOUT
R
R
BOT
R
C
C
CP
where:
ESR
C
C
R
R
DS(ON)_HS is the high-side MOSFET on resistance.
DS(ON)_LS is the low-side MOSFET on resistance.
D is the duty cycle (D = VOUT/VIN).
Figure 40. Simplified Peak Current-Mode Control Small Signal Circuit
Switching Loss (PSW)
The compensation components, RC and CC, contribute a zero
and the optional CCP and RC contribute an optional pole.
Switching losses are associated with the current drawn by the
driver to turn the power devices on and off at the switching
frequency. Each time a power device gate is turned on or off,
the driver transfers a charge from the input supply to the gate,
and then from the gate to ground. Use the following equation to
estimate the switching loss:
The closed-loop transfer (TV(s)) equation is as follows:
1+ RC × CC × s
RC ×CC ×CCP
RBOT
BOT + RTOP CC+ CCP
−gm
TV(s) =
×
×
×Gvd(s)
R
s × 1+
× s
CC + CCP
P
SW = (CGATE_HS + CGATE_LS) × VIN2 × fSW
The following procedure shows how to select the compensation
components—RC, CC, and CCP,—for ceramic output capacitor
applications.
where:
CGATE_HS is the gate capacitance of the high-side switch.
GATE_LS is the gate capacitance of the low-side switch.
C
1. Determine the cross frequency (fC). Generally, fC is between
fSW/12 and fSW/6.
2. RC can be calculated using the following equation:
f
SW is the switching frequency.
Transition Loss (PTRAN
)
Transition losses occur because the high-side switch cannot
turn on or off instantaneously. During a switch node transition,
the power switch provides all the inductor current. The source
to drain voltage of the power switch is half the input voltage,
resulting in power loss. Transition losses increase with both
load and input voltage and occur twice for each switching cycle.
Use the following equation to estimate the transition loss:
2 × π×VOUT ×COUT × fC
RC
=
VSETx × gm × AVI
3. Place the compensation zero at the domain pole (fP).
CC can be determined as follows:
(
R + RESR × COUT
)
CC =
RC
CP is optional. It can be used to cancel the zero caused by
the ESR of the output capacitor.
P
TRAN = 0.5 × VIN × IOUT × (tR + tF) × fSW
4.
C
where:
tR is the rise time of the switch node.
tF is the fall time of the switch node.
R
ESR ×COUT
CCP
=
Thermal Shutdown
RC
When the ADP5014 operates under a heavy load in a high
ambient temperature, the power loss can cause the junction
temperature to exceed the maximum junction temperature of
125°C. If the junction temperature exceeds 150°C, the regulator
enters thermal shutdown and recovers when the junction
temperature falls below 135°C.
POWER DISSIPATION
The total power dissipation in the ADP5014 (PD) simplifies to
PD = PBUCK1 + PBUCK2 + PBUCK3 + PBUCK4
Buck Regulator Power Dissipation
The power dissipation (PLOSS) for each buck regulator includes
power switch conductive losses (PCOND), switch losses (PSW), and
transition losses (PTRAN). Other sources of power dissipation exist,
but these sources are generally less significant at the high output
currents of the application thermal limit.
Use the following equation to estimate the power dissipation of
the buck regulator:
P
LOSS = PCOND + PSW + PTRAN
Rev. A | Page 25 of 34
ADP5014
Data Sheet
ambient temperature of the package (see Table 4). Thermal
JUNCTION TEMPERATURE
performance is directly linked to PCB design and operating
environment. Careful attention to PCB thermal design is
required.
PD is the power dissipation in the package.An important factor
to consider is that the thermal resistance value is based on a
4-layer, 4 inch × 3 inch PCB with 2.5 oz of copper, as specified
in the JEDEC standard, whereas real world applications can use
PCBs with different dimensions and a different number of
layers.
The junction temperature of the die is the sum of the ambient
temperature of the environment and the temperature rise of the
package due to power dissipation, as shown in the following
equation:
TJ = TA + TR
where:
TJ is the junction temperature.
TA is the ambient temperature.
TR is the rise in temperature of the package due to power
dissipation.
It is important to maximize the amount of copper used to
remove heat from the device. Copper exposed to air dissipates
heat better than copper used in the inner layers. The exposed
pad is connected to the ground plane with several vias.
The rise in temperature of the package is directly proportional
to the power dissipation in the package. The proportionality
constant for this relationship is the thermal resistance from the
junction of the die to the ambient temperature, as shown in the
following equation:
TR = θJA × PD
where:
TR is the rise in temperature of the package.
θJA is the thermal resistance from the junction of the die to the
Rev. A | Page 26 of 34
Data Sheet
ADP5014
DESIGN EXAMPLES
This section provides an example of the step by step design
procedures and the external components required for Channel 1.
Table 12 lists the design requirements for this example.
To set the output voltage to 1.2 V, choose the following resistor
values: R1 = 6.65 kΩ, and R2 = 10 kΩ.
SETTING THE CONFIGUATIONS (CFG1 AND CFG2)
Table 12. Example Design Requirements for Channel 1
The CFG1 pin can be used to program the load output
capability and parallel operation for all channels. For this
example, choose RCFG1 = 0 kΩ. For more information, see the
configuration in Function Configurations (CFG1 and CFG2).
Parameter
Specification
Input Voltage
Output Voltage
Output Current
Output Ripple
Load Transient
VPVIN1 = 5 V 5%
VOUT1 = 1.2 V
IOUT1 = 4 A
ΔVOUT1_RIPPLE = 5 mV in CCM mode
5%, at 20% to 80% load transient, 1 A/µs
The CFG2 pin can be used to program the operation mode
(FPWM or PWM/PSM mode), the enable mode (manual mode
or sequence mode), the timer (×1 or ×8), and GPIO functionalities
(PWRGD, SYNC-IN, CLK-OUT, UVO) for all channels. For
this example, choose RCFG2 = 0 kΩ. For more information, see the
configuration in Function Configurations (CFG1 and CFG2).
Although this example shows step by step design procedures for
Channel 1, the procedures apply to all other buck regulator
channels (Channel 2 to Channel 4).
SELECTING THE INDUCTOR
SETTING THE SWITCHING FREQUENCY
The peak-to-peak inductor ripple current, ΔIL, is set to 30% of
the maximum output current. Use the following equation to
estimate the value of the inductor (L):
The first step when setting the switching frequency is to determine
the switching frequency for the ADP5014 design. In general,
higher switching frequencies produce a smaller solution size
due to the lower component values required, whereas lower
switching frequencies result in higher conversion efficiency due
to lower switching losses.
(VIN − VOUT ) ×D
L =
∆IL × fSW
where:
VIN = 5 V.
The switching frequency of the ADP5014 can be set to a value
from 500 kHz to 2.5 MHz by connecting a resistor from the RT
pin to ground. The selected resistor allows users to make
decisions based on the trade-off between efficiency and solution
size. For more information, see the Oscillator section.
V
OUT = 1.2 V.
D is the duty cycle (D = VOUT/VIN = 0.24).
ΔIL = 30% × 4 A = 1.2 A.
f
SW = 1.2 MHz.
However, the highest supported switching frequency must be
assessed by checking the voltage conversion limitations
enforced by the minimum on time and the minimum off time
(see the Voltage Conversion Limitations section).
The resulting value for L is 0.63 µH. The closest standard
inductor value is 0.8 µH; therefore, the inductor ripple current,
ΔIL1, is 0.95 A.
The inductor peak current is calculated using the following
equation:
In this design example, a switching frequency of 1.2 MHz
achieves a good combination of small solution size and high
conversion efficiency. To set the switching frequency to
1.2 MHz, use the following equation to calculate the resistor
value, RRT:
I
PEAK = IOUT + (ΔIL/2)
The calculated peak current for the inductor is 4.48 A.
The rms current of the inductor can be calculated using the
following equation:
R
RT (kΩ) = (100,000/fSW (kHz))
According to this equation, select standard resistor RRT
82.5 kΩ.
=
2
∆IL
12
2
IRMS
=
IOUT
+
SETTING THE OUTPUT VOLTAGE
The rms current of the inductor is approximately 4.01 A.
Therefore, an inductor with a minimum rms current rating of
4.01 A and a minimum saturation current rating of 4.48 A is
required. However, to prevent the inductor from reaching its
saturation point in current-limit conditions, it is recommended
that the inductor saturation current be higher than the maximum
peak current limit, typically 6 A, for reliable operation.
Because the desired output voltage setting is less than VREF
voltage, use the resistor divider from the accurate internal
VREF reference voltage to set the desired output voltage and
directly tie the feedback pin (FB1) to the output (see Figure 38).
Select a 10 kΩ bottom resistor (R2) and then calculate the top
resistor using the following equation:
R1 = R2 × ((VREF − VOUT)/VOUT
)
Based on these requirements and recommendations, the
COILCRAFT XAL5030-801MEB, with a direct current
resistance (DCR) of 5.14 mΩ, is selected for this design.
where:
V
V
OUT is the output voltage.
REF is 2.0 V for Channel 1 to Channel 4.
Rev. A | Page 27 of 34
ADP5014
Data Sheet
120
100
80
120
100
80
SELECTING THE OUTPUT CAPACITOR
The output capacitor must meet the output voltage ripple and
load transient requirements. To meet the output voltage ripple
requirement, use the following equation to calculate the ESR
and capacitance:
60
60
40
40
20
20
0
0
∆IL
COUT _ RIPPLE
=
–20
–40
–60
–80
–100
–120
–20
–40
–60
–80
–100
–120
8 × fSW × ∆VOUT _ RIPPLE
∆VOUT _ RIPPLE
∆IL
RESR
=
CROSS FREQUENCY = 132kHz
PHASE MARGIN = 56°
The calculated capacitance, COUT_RIPPLE, is 19.8 µF, and the
calculated RESR is 5 mΩ.
1k
10k
100k
FREQUENCY (Hz)
1M
Figure 41. Bode Plot for 1.2 V Output
To meet the 5% overshoot and undershoot requirements,
use the following equations to calculate the capacitance:
KUV × ∆ISTEP 2 × L
COUT _UV
=
=
2×
(
VIN − VOUT × ∆VOUT _UV
)
1
KOV × ∆ISTEP 2 × L
COUT _OV
2
2
VOUT + ∆VOUT_OV
− VOUT
For estimation purposes, use KOV = KUV = 2; therefore,
OUT_OV = 62.4 µF and COUT_UV = 20.2 µF.
C
The ESR of the output capacitor must be less than 5 mΩ,
and the output capacitance must be greater than 62.4 µF. It is
recommended that two ceramic capacitors be used (47 µF, X5R,
6.3 V), such as the GRM21BR60J476ME15 from Murata with
an ESR of 2 mΩ.
4
B
CH1 5.00mV
M100µs
25.8%
A CH4
2.16A
W
T
CH4 2A Ω
Figure 42. Selecting the Input Capacitor
DESIGNING THE COMPENSATION NETWORK
For the input capacitor, select a ceramic capacitor with a
minimum value of 10 µF. The input capacitor is placed close to
the PVINx pin. In this example, one ceramic capacitor of 10 µF,
X5R, 16 V is recommended.
For better load transient and stability performance, set the cross
frequency, fC, to fSW/10. In this example, fSW is set to 1.2 MHz;
therefore, fC is set to 120 kHz.
For the 1.2 V output rail, the 47 μF ceramic output capacitor has
a derated value of 32 µF.
LOW NOISE OUTPUT DESIGN
The ADP5014 optimizes many analog blocks and uses new unity-
gain reference architecture to achieve lower output noise in low-
frequency range. When the system design needs the low noise
output of ADP5014 , the device enables powering up the signal
chain products directly without LDOs. In this scenario, adding
an additional LC filter is highly recommended after the main
LC filter to filter the fundamental switching ripple and its
harmonic. This is because the switching ripples may generate
unexpected noise spurs for the noises sensitive signal chain
devices. Because this additional inductor filter may generate
voltage drop at the load, the inductor with small DCR is
recommended to minimize the voltage drop, especially for high
current applications.
2 × π ×1.2 V× 2 ×32µF×120 kHz
RC =
CC =
= 3.62 k Ω
= 5.32 nF
1.2 V × 800µs ×16.67A/V
(
0.3Ω + 0.001 Ω × 2 × 32µF
)
3.62 k Ω
0.001 Ω × 2 ×32 µF
3.62 k Ω
CCP
=
= 17.7 pF
Choose standard components: RC = 3.57 kΩ and CC = 5.6 nF.
CP is optional.
C
Figure 41 shows the bode plot for the 1.2 V output rail. The
cross frequency is 132 kHz, and the phase margin is 56°. The
load transient waveform is shown in Figure 42.
Figure 43 and Figure 44 show the ADP5014 noise spectral
density measurement from a 10 Hz to 10 MHz frequency range
and integrated rms noise from a 10 Hz to 1 MHz frequency
range, compared to the ADP1740 as another traditional, 2 A,
low noise linear regulator.
Rev. A | Page 28 of 34
Data Sheet
ADP5014
10k
50
45
40
35
30
25
20
15
10
5
ADP5014
ADP1740
ADP5014
ADP1740
1k
100
10
1
0.1
10
0
10
100
1k
10k
100k
1M
10M
100
1k
10k
100k
1M
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 43. ADP5014 Noise Spectral Density Measurement, VIN = 5 V, VOUT1
1.3 V, IOUT1 = 0.5 A, fSW = 1.2 MHz, L1 = 0.8 μH, COUT = 47 μF × 3, LFILTER = 1 μH,
CFILTER = 22 μF × 2
=
Figure 44. ADP5014 Integrated RMS Noise, VIN = 5 V, VOUT1 = 1.3 V, IOUT1 = 0.5 A,
fSW = 1.2 MHz, L1 = 0.8 μH, COUT = 47 μF × 3, LFILTER = 1 μH, CFILTER = 22 μF × 2
Rev. A | Page 29 of 34
ADP5014
Data Sheet
PCB LAYOUT RECOMMENDATIONS
Good circuit board layout is essential to obtain the best
performance from the ADP5014 (see Figure 45). Poor layout can
affect the regulation and stability of the device, as well as the
EMI and electromagnetic compatibility (EMC) performance.
Refer to the following guidelines for a good PCB layout.
•
•
Maximize the amount of ground metal for the exposed pad,
and use as many vias as possible on the component side to
improve thermal dissipation.
Use a ground plane with several vias connecting to the
component side ground to further reduce noise
interference on sensitive circuit nodes.
•
Place the input capacitor, inductor, and output capacitor
close to the IC.
•
•
•
•
Place the decoupling capacitors close to the VREF pin.
Place the RC filter close to the AVIN pin.
•
Use short, thick traces to connect the input capacitors
to the PVINx pins, and use dedicated power ground to
connect the input and output capacitor grounds to
minimize the connection length.
Place the frequency setting resistor close to the RT pin.
Place the VREF resistor divider close to the VSETx and the
feedback resistor divider close to the FBx pin. In addition,
keep the VSETx and FBx traces away from the high current
traces and the switch node to avoid noise pickup.
Use size 0402 or 0603 resistors and capacitors to achieve
the smallest possible footprint solution on boards where
space is limited.
•
•
•
Use several high current vias, if required, to connect
PVINx, PGNDx, or SWx to other power planes.
Use short, thick traces to connect the inductors to the
SWx pins and the output capacitors.
Ensure that the high current loop traces are as short and wide
as possible.
•
R0402
R0402
R0402
R0402
47µF
6.5V/XR5
0805
VSET4 VSET3 VREF VSET2 VSET1 RT
FB3
AVIN
FB1 COMP1 PVIN1
PVIN1 30
1
2
3
4
5
6
7
8
9
VOUT1
29
SW1
COMP3
PVIN3
SW3
47µF
6.3V/XR5
0805
SW1 28
PGND1 27
PGND1 26
PGND2 25
47µF
6.3V/XR5
0603
PGND3
PGND4
SW4
ADP5014
6mm × 6mm
47µF
6.3V/XR5
0603
PGND2
24
SW2 23
PVIN4
COMP4
47µF
6.3V/XR5
0805
SW2
22
PVIN2 21
10 FB4
EN4/
EN2/ EN1/
GPIO DL34 EN3/UV CFG2 CFG1 DL12 ENALL FB2 COMP2 PVIN2
VOUT2
47µF
6.3V/XR5
0805
R0402
R0402
Figure 45. Typical PCB Layout for the ADP5014
Rev. A | Page 30 of 34
Data Sheet
ADP5014
TYPICAL APPLICATION CIRCUITS
ADP5014
VREF
0.47µF
RT
OSC
REF
82.5kΩ
EN1/ENALL
EN2/DL12
VREF
CFG1
0Ω
CFG2 31.6kΩ
0Ω
EN3/UV
LOGIC DECODER
EN4/DL34
GPIO
FB1
26.1kΩ
AVIN
5.0V
PVIN1
PVIN1
C2
C1
SW1
10µF
1µF
L1
CH 1
BUCK
(2A/4A)
VOUT1
1.2V/4A
VCORE
0.8µH
VREF
SW1
C3
47µF
C4
47µF
C5
47µF
VSET1
13.3kΩ
PGND1
20kΩ
FPGA
COMP1
PGND1
20kΩ
4.32kΩ
10nF
FB2
PVIN2
4.99kΩ
L2
0.8µH
AUXILIARY
VOLTAGE
SW2
C6
10µF
CH 2
BUCK
(2A/4A)
PVIN2
VSET2
VOUT2
2.5V/2A
VREF
10nF
SW2
C7
47µF
C8
47µF
BANK 0
BANK 1
PGND2
I/Os
BANK 2
COMP2
PGND2
4.32kΩ
PVIN3
L3
SW3
FB3
VOUT3
1.5V/2A
I/Os
BANK 3
C9
1.5µH
10µF
C10
47µF
CH 3
BUCK
(1A/2A)
VREF
VSET3
6.65kΩ
20kΩ
10nF
PGND3
DDR
TERM. LDO
DDR3 MEMORY
FLASH MEMORY
COMP3
4.32kΩ
PVIN4
L4
VOUT4
3.3V/2A
SW4
FB4
C11
10µF
1.5µH
C12
47µF
CH 4
BUCK
(1A/2A)
VREF
VSET4
13kΩ
20kΩ
PGND4
COMP4
6.04kΩ
10nF
AGND
EXPOSED PAD
ENALL
2ms
36ms
24ms
1.2V
6ms
2.5V/1.5V
3.3V
12ms
12ms
Figure 46. Typical Field Programmable Gate Array (FPGA) Application, 1.2 MHz Switching Frequency, Sequence Enable Mode
Rev. A | Page 31 of 34
ADP5014
Data Sheet
ADP5014
VREF
0.47µF
RT
OSC
REF
82.5kΩ
VREF
CFG1
EN1/ENALL
EN2/DL12
0Ω
CFG2 31.6kΩ
17.8kΩ
EN3/UV
LOGIC DECODER
EN4/DL34
GPIO
FB1
56.2kΩ
AVIN
5.1kΩ
RF TRANSCEIVER
5.0V
PVIN1
PVIN1
C2
3.3nF
VOUT1
C1
L1
1µH
L5
220nH
SW1
10µF
1µF
CH 1
BUCK
(2A/4A)
1.3V/3000mA
1.3V ANALOG
VREF
SW1
C3
47µF
C4
C5
47µF
C6
47µF
VSET1
10.7kΩ
47µF
PGND1
0.1Ω
1.3V VDD_JESD
20kΩ
COMP1
PGND1
FB2
4.32kΩ
10nF
5.1kΩ
PVIN2
3.3nF
C7
L6
220nH
SW2
L2
1µH
CH 2
BUCK
(2A/4A)
10µF
PVIN2
VSET2
1.3V/1500mA
VOUT2
VREF
1.3V DIGITAL
10.7kΩ
SW2
PGND2
C8
47µF
C9
47µF
C10
47µF
C11
47µF
20kΩ
0.1Ω
COMP2
PGND2
4.32kΩ
10nF
L3
PVIN3
VSET3
1.5µH
SW3
FB3
VOUT3
3.3V/600mA
3.3V VDD_GPO
C12
10µF
C13
47µF
CH 3
BUCK
(1A/2A)
VREF
18nF
13kΩ
20kΩ
COMP3
PGND3
6.04kΩ
PVIN4
VSET4
1.8V LVDS/CMOS
1.8V TX
C14
10µF
L4
1.5µH
L8
220nH
CH 4
BUCK
(1A/2A)
VREF
1.8V/600mA
SW4
VOUT4
2.21kΩ
20kΩ
C15
47µF
C16
47µF
C17
47µF
FB4
COMP4
PGND4
0.1Ω
3.3nF
5.1kΩ
4.32kΩ
15nF
AGND
EXPOSED PAD
ENALL
2ms
36ms
24ms
1.3V DIG
1.3V ANA
6ms
3.3V VDD/
1.8V TX
12ms
12ms
Figure 47. Typical RF Transceiver Application, 1.2 MHz Switching Frequency, Sequence Enable Mode
Rev. A | Page 32 of 34
Data Sheet
ADP5014
FACTORY PROGRAMMABLE OPTIONS
FACTORY DEFAULT OPTIONS
Table 13 lists the factory default options programmed into the ADP5014 when the device is ordered (see the Ordering Guide). To order
the device with options other than the default options, contact your local Analog Devices sales or distribution representative.
Table 13. Factory Default Options
Option
Default Value
Channel 1 Output Voltage
Channel 2 Output Voltage
Channel 3 Output Voltage
Channel 4 Output Voltage
PWRGD Pin Output
Adjustable output
Adjustable output
Adjustable output
Adjustable output
Monitor all Channel 4 outputs (enabled by the CFG2 configuration)
Enabled for all four buck regulators
Hiccup protection enabled for overcurrent events
Output Discharge Function
Hiccup Detection
Rev. A | Page 33 of 34
ADP5014
Data Sheet
OUTLINE DIMENSIONS
DETAIL A
(JEDEC 95)
6.10
6.00 SQ
5.90
0.30
0.23
0.18
PIN 1
INDICATOR
AREA
PIN 1
40
INDICATOR AR EA OP TIONS
31
(SEE DETAIL A)
30
1
0.50
BSC
4.45
EXPOSED
PAD
4.30 SQ
4.25
21
20
10
11
0.45
0.40
0.35
0.20 MIN
TOP VIEW
SIDE VIEW
BOTTOM VIEW
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
0.80
0.75
0.70
0.05 MAX
0.02 NOM
SECTION OF THIS DATA SHEET.
COPLANARITY
0.08
0.20 REF
SEATING
PLANE
COMPLIANT TO JEDEC STANDARDS MO-220-WJJD-5
Figure 48. 40-Lead Lead Frame Chip Scale Package [LFCSP]
6 mm × 6 mm Body, and 0.75 mm Package Height
(CP-40-10)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature Range
−40°C to +125°C
Package Description
Package Option2
CP-40-10
ADP5014ACPZ-R7
ADP5014-EVALZ
40-Lead Lead Frame Chip Scale Package [LFCSP]
Evaluation Board
1 Z = RoHS Compliant Part.
2 Table 13 lists the factory default options for the device. For a list of factory programmable options, see the Factory Programmable Options section. To order a device
with options other than the default values, contact your local Analog Devices sales or distribution representative.
©2017–2019 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D15496-0-8/19(A)
Rev. A | Page 34 of 34
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