TPS92200D2DDCR [TI]
TPS92200 4-V to 30-V Input Voltage, 1.5-A Output Current, Synchronous Buck LED Driver With Flexible Dimming Options;
| 型号： | TPS92200D2DDCR |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | TPS92200 4-V to 30-V Input Voltage, 1.5-A Output Current, Synchronous Buck LED Driver With Flexible Dimming Options |
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| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
TPS92200
SLVSER4A – MAY 2020 – REVISED SEPTEMBER 2021
TPS92200 4-V to 30-V Input Voltage, 1.5-A Output Current,
Synchronous Buck LED Driver With Flexible Dimming Options
1 Features
3 Description
•
•
4-V to 30-V wide input range
Integrated 150-mΩ and 90-mΩ MOSFETs for
1.5-A continuous output current
Ultra-low shut-down current: 1 μA
Ultra-low output discharge current from load: 1 μA
1-MHz switching frequency
Maximum duty cycle up to 99%
Peak current mode with internal compensation
Flexible dimming options:
The TPS92200 device is a 1.5-A synchronous
buck LED driver with 30-V maximum input voltage.
By integrating the high-side and low-side NMOS
switches, the TPS92200 device provides high power
density with high efficiency in an ultra-small solution
size. The TPS92200 device uses peak-current-mode
control and full internal compensation to provide high
transient response performance over a wide range of
operating conditions.
•
•
•
•
•
•
– TPS92200D1: PWM dimming with digital input
and analog dimming with analog input
– TPS92200D2: analog dimming with digital input
Ultra-low and accurate FB voltage: 99 mV ±3 mV
Full protection features:
The TPS92200 device supports flexible dimming
methods. TPS92200D1 implements both PWM and
analog dimming modes. In PWM dimming mode,
LEDs turn on and off according to PWM duty cycle
periodically. The device's analog dimming mode is
achieved by changing the internal reference voltage
proportional to the voltage level of the analog input in
5% to 100% range. TPS92200D2 implements deeper
analog dimming by changing the internal reference
voltage proportional to the duty cycle of the PWM
signal input in 1% to 100% range.
•
•
– LED open-load protection
– LED+ short-to-GND protection with auto-retry
– LED+ and LED– short circuitry protection with
auto-retry
– Sense-resistor open-load and short-to-GND
protection with auto-retry
– Thermal shutdown protection with auto-retry
SOT23 (6) package
VQFN-HR (6) package
For safety and protection, the TPS92200 devices
implement full protections, including LED open, LED+
short-to-GND, LED short, sense resistor open and
short, and device thermal protection.
•
•
2 Applications
•
•
•
•
•
•
Video surveillance IR/White LED driver
Facial recognition IR LED driver
Stage lighting LED driver
General industrial and commercial illumination
Medical UV LED driver
Device Information
PART NUMBER
TPS92200D1DDCR
TPS92200D2DDCR
PACKAGE
SOT-23-THIN (6)
SOT-23-THIN (6)
BODY SIZE (NOM)
1.60 mm × 2.90 mm
1.60 mm × 2.90 mm
1.50 mm × 2.00 mm
1.50 mm × 2.00 mm
TPS92200D1RXLR(1) VQFN-HR (6)
TPS92200D2RXLR(1) VQFN-HR (6)
AA or Li-Ion battery charger
(1) Product preview status only.
COUT
L
RSENSE
RFB
FB
BOOT
SW
CBOOT
EN/DIM Input
DIM
GND
RDIM
VIN
VIN
CIN
Simplified Schematic
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
TPS92200
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SLVSER4A – MAY 2020 – REVISED SEPTEMBER 2021
Table of Contents
1 Features............................................................................1
2 Applications.....................................................................1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Pin Configuration and Functions...................................3
6 Specifications.................................................................. 4
6.1 Absolute Maximum Ratings ....................................... 4
6.2 ESD Ratings .............................................................. 4
6.3 Recommended Operating Conditions ........................4
6.4 Thermal Information ...................................................4
6.5 Electrical Characteristics ............................................5
6.6 Timing Requirements .................................................6
6.7 Switching Characteristics ...........................................6
6.8 Typical Characteristics................................................7
7 Detailed Description......................................................10
7.1 Overview...................................................................10
7.2 Functional Block Diagram.........................................10
7.3 Feature Description...................................................11
7.4 Device Functional Modes..........................................15
8 Application and Implementation..................................17
8.1 Application Information............................................. 17
8.2 Typical Application.................................................... 17
9 Power Supply Recommendations................................30
10 Layout...........................................................................30
10.1 Layout Guidelines................................................... 30
10.2 Layout Example...................................................... 30
11 Device and Documentation Support..........................32
11.1 Receiving Notification of Documentation Updates..32
11.2 Support Resources................................................. 32
11.3 Trademarks............................................................. 32
11.4 Electrostatic Discharge Caution..............................32
11.5 Glossary..................................................................32
12 Mechanical, Packaging, and Orderable
Information.................................................................... 32
4 Revision History
Changes from Revision * (May 2020) to Revision A (September 2021)
Page
•
•
•
•
•
Updated the numbering format for tables, figures and cross-references throughout the document...................1
Added VQFN-HR package information...............................................................................................................1
Added VQFN-HR package information...............................................................................................................1
Add VQFN-HR package information...................................................................................................................3
Added VQFN-HR package information.............................................................................................................30
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5 Pin Configuration and Functions
FB
DIM
1
2
3
6
5
4
BOOT
SW
GND
VIN
Not to scale
Figure 5-1. DDC Package 6-Pin SOT-23-THIN Top View
BOOT
1
6
5
FB
DIM
SW
VIN
2
3
4
GND
Figure 5-2. RXL Package 6-Pin VQFN-HR Top View
Table 5-1. Pin Functions
PIN
TYPE(1)
DESCRIPTION
NAME DDC NO. RXL NO.
BOOT
FB
6
1
3
1
6
4
O
I
A bootstrap capacitor is required between BOOT and SW.
LED current detection feedback
Power ground
GND
G
Dimming input. In PWM dimming mode, LED current is turned ON and
OFF according to PWM duty cycle periodically (TPS92200D1). In analog
dimming mode, the internal reference is proportional to the analog voltage
on DIM pin (TPS92200D1) or the PWM duty input (TPS92200D2).
DIM
2
5
I
SW
VIN
5
4
2
3
O
P
Switching node to external inductor
Input supply voltage
(1) I = Input, O = Output, P = Supply, G = Ground
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6 Specifications
6.1 Absolute Maximum Ratings
over operating ambient temperature range (unless otherwise noted)(1)
MIN
–0.3
–0.3
–0.3
–0.3
–0.3
–5
MAX
UNIT
V
IN
32
7
Input voltage range, VI
DIM
V
FB
7
V
BOOT-SW
SW
7
V
Output voltage range, VO
32
32
150
150
V
SW (20 ns transient)
V
Operating junction temperature, TJ
Storage temperature range, Tstg
–40
–65
°C
°C
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Theseare stress
ratings only, which do not imply functional operation of the device at these or anyother conditions beyond those indicated
under Recommended OperatingConditions. Exposure to absolute-maximum-rated conditions for extended periods mayaffect device
reliability.
6.2 ESD Ratings
VALUE
±2000
±500
UNIT
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)
V(ESD)
Electrostatic discharge
V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2)
(1) JEDEC document JEP155 states that 500-V HBM allows safemanufacturing with a standard ESD control process.
(2) JEDEC document JEP157 states that 250-V CDM allows safemanufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating ambient temperature range (unless otherwise noted)
MIN
4
MAX
UNIT
IN
30
6
V
V
Input voltage range
DIM
–0.1
–0.1
–0.1
–0.1
–40
FB
6
V
BOOT-SW
SW
6
V
Output voltage range
30
125
V
Operating Junction temperature, TJ
°C
6.4 Thermal Information
TPS92200
DDC (SOT-23-6)
6 PINS
123.4
TPS92200
THERMAL METRIC(1)
RXL (VQFN-HR-6)
UNIT
6 PINS
136.1
95.3
RθJA
RθJC(top)
RθJB
ψJT
Junction-to-ambient thermal resistance
Junction-to-case (top) thermal resistance
Junction-to-board thermal resistance
°C/W
°C/W
°C/W
°C/W
°C/W
60.5
41.4
49.3
Junction-to-top characterization parameter
Junction-to-board characterization parameter
12.3
4.6
ψJB
40.9
48.1
(1) For more information about traditional and new thermalmetrics, see the Semiconductor and IC Package Thermal Metricsapplication
report, SPRA953.
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6.5 Electrical Characteristics
The electrical ratings specified in this section apply to all specifications in thisdocument, unless otherwise noted. These
specifications are interpreted as conditions that do notdegrade the device parametric or functional specifications for the life of
the product containingit. TJ = –40°C to +125°C, VIN = 4 V to 30 V, (unlessotherwise noted).
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX UNIT
INPUT SUPPLY
VIN
Input voltage range
4
3.5
3.3
30
3.9
3.7
V
V
Rising VIN
Falling VIN
3.7
3.5
0.2
1
VIN undervoltage lockout
VIN_UVLO
V
Hysteresis
V
ISD
Shut down current from VIN
Discharge current from SW and BOOT
Normal operating current
VIN = 12 V, VDIM = 0 V
VIN floating, VDIM = 0 V
VDIM = 3.3 V
3
3
1
µA
uA
mA
IDISC
1
IOP
0.5
DIMMING
VDIM_L
VDIM_H
VANA
Low-level input voltage
0.3
V
V
V
High-level input voltage
0.65
0.65
Analog dimming range (TPS92200D1 only)
1.2
DIM minimum on time to enable device
(TPS92200D2 only)
tDIM_ON1
VDIM = 3.3 V
190
36
300
nS
DIM minimum on time when PWM dimming
(TPS92200D2 only)
tDIM_ON2
tDIM_OFF
VDIM = 3.3 V
VDIM = 0 V
150
102
nS
DIM minimum off time to disable device
mS
FEEDBACK AND ERROR AMPLIFIER
VFB_REF FB pin reference voltage
VFB_OVP
VDIM = 3.3 V
VDIM = 3.3 V
96
99
mV
mV
FB pin overvoltage protection threshold
140
FB reference voltage when maximum dimming
input (TPS92200D1 only)
VFB_DMAX
VDIM = 1.2 V
99
5
mV
mV
mV
FB reference voltage when minimum dimming
input (TPS92200D1 only)
VDIM = 0.65 V
VFB_DMIN
FB reference voltage when minimum dimming
duty cycle (TPS92200D2 only)
DIM pin duty cycle <= 3%
1
POWER STAGE
RHS
High-side FET on resistance
Low-side FET on resistance
VIN ≥ 5 V
VIN ≥ 5 V
150
90
mΩ
mΩ
RLS
CURRENT LIMIT
ILIM_HS
High-side current limit
2.9
2.4
1.4
3.3
3
4
3.6
2.4
A
A
A
ILIM_LS_SOUR
ILIM_LS_SINK
Low-side sourcing current limit
Low-side sinking current limit
1.8
THERMAL PROTECTION
Thermal shutdown temperature
Hysteresis
165
15
°C
°C
TTSD
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UNIT
SLVSER4A – MAY 2020 – REVISED SEPTEMBER 2021
6.6 Timing Requirements
MIN
TYP
MAX
AUTO-RETRY TIMING
tRETRY_ON
tRETRY_OFF
SOFT START
tSS
Auto-retry on-time
Auto-retry off-time
512
60
Cycles
ms
Internal soft-start time
0.5
ms
6.7 Switching Characteristics
TJ = –40°C to +125°C, VIN = 4V to 30V, (unless otherwise noted).
PARAMETER
Switching frequency
Maximum duty cycle
Minimum on time
Minimum off time
Maximum on time
TEST CONDITIONS
MIN
0.8
TYP
MAX
UNIT
fsw
1
99%
75
1.2
MHz
DMAX
tMIN_ON
tMIN_OFF
tMAX_ON
100
90
ns
ns
us
65
6.6
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6.8 Typical Characteristics
VIN = 12 V, unless otherwise specified.
1100
1080
1060
1040
1020
1000
980
3
2.5
2
1.5
1
960
940
0.5
0
920
900
0
5
10
15 20
Input Voltage (V)
25
30
35
-50
-25
0
25
50
75
100
125
150
D011
Junction Temperature (èC)
D006
Figure 6-1. Output Current vs Input Voltage
Figure 6-2. Shutdown Current vs Junction Temperature
1100
1080
1060
1040
1020
1000
980
120
100
80
60
40
20
0
960
940
920
900
0
1
2
3 4
LED Count
5
6
7
0
0.2
0.4
0.6
0.8
1
DIM Voltage (V)
1.2
1.4
1.6
D012
D004
Figure 6-3. Output Current vs LED Count
Figure 6-4. DIM Voltage vs FB Voltage in Analog Dimming (for
TPS92200D1)
100
90
80
70
60
50
40
30
20
10
0
1.6
1.4
1.2
1
0.8
0.6
0.4
0
10
20
30
40
50
60
DIM Duty Cycle (%)
70
80
90 100
-50
-25
0
25
50
75
100
125
150
Junction Temperature (èC)
D005
D007
Figure 6-5. DIM Duty Cycle vs FB Voltage in Analog Dimming
(for TPS92200D2)
Figure 6-6. Switching Frequency vs Junction Temperature
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6.8 Typical Characteristics (continued)
VIN = 12 V, unless otherwise specified.
3.775
3.75
0.7
0.65
0.6
3.725
3.7
Rising
Falling
0.55
0.5
3.675
3.65
3.625
3.6
0.45
0.4
3.575
3.55
0.35
0.3
3.525
-40
-20
0
20
40
60
80
100 120 140
-50
-25
0
25
50
75
100
125
150
Junction Temperature (èC)
Junction Temperature (èC)
D004
D009
Figure 6-7. VIN UVLO Threshold vs Junction Temperature
Figure 6-8. DIM Enable Threshold vs Junction Temperature
0.7
0.65
0.6
300
250
200
150
100
50
0.55
0.5
0.45
0.4
0.35
0.3
0
-50
-25
0
25
50
75
100
125
150
-40 -25 -10
5
20 35 50 65 80 95 110 125
Junction Temperature (èC)
Junction Temperature (èC)
D010
D013
Figure 6-9. DIM Shutdown Threshold vs Junction Temperature
Figure 6-10. High-side FET On Resistance vs Junction
Temperature
200
160
120
80
3.6
3.5
3.4
3.3
3.2
3.1
3
40
0
-40 -25 -10
5
20 35 50 65 80 95 110 125
Junction Temperature (èC)
-40 -25 -10
5
20 35 50 65 80 95 110 125
Junction Temperature (èC)
D014
D015
Figure 6-11. Low-Side FET On Resistance vs Junction
Temperature
Figure 6-12. High-Side FET Source Current Limit vs Junction
Temperature
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6.8 Typical Characteristics (continued)
VIN = 12 V, unless otherwise specified.
3.2
1.9
1.8
1.7
1.6
1.5
3.1
3
2.9
2.8
2.7
2.6
-40 -25 -10
5
20 35 50 65 80 95 110 125
Junction Temperature (èC)
-40 -25 -10
5
20 35 50 65 80 95 110 125
Junction Temperature (èC)
D016
D017
Figure 6-13. Low-Side FET Source Current Limit vs Junction
Temperature
Figure 6-14. Low-Side FET Sink Current Limit vs Junction
Temperature
100
90
80
70
60
50
40
100
90
80
70
60
50
40
30
30
1IRLED
2IRLED
1IRLED
2IRLED
20
20
4IRLED
6IRLED
4IRLED
6IRLED
10
0
10
0
0
20
40 60
PWM Duty Cycle (%)
80
100
0
20
40 60
PWM Duty Cycle (%)
80
100
D002
D001
Figure 6-15. Efficiency at 1-A Output Current, 4.7-µH Inductor,
12-V Input Voltage
Figure 6-16. Efficiency at 1.5-A Output Current, 4.7-µH Inductor,
12-V Input Voltage
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7 Detailed Description
7.1 Overview
The TPS92200 device is a 1.5-A synchronous buck LED driver with 30-V maximum input voltage. By integrating
the high-side and low-side NMOS switches, the TPS92200 device provides high power density with high
efficiency in an ultra-small solution size.
The TPS92200 device is fully internally compensated without additional external components, which enables
a simple design on a limited board space. The device uses peak current mode control to regulate the LED
current with high accuracy. Switching frequency is internally set to 1 MHz, allowing the use of extremely small
surface-mount inductors and chip capacitors.
The TPS92200 devices support flexible dimming methods. TPS92200D1 implement both PWM and analog
dimming modes. In PWM dimming mode, the LED turns on and off according to PWM duty cycle periodically.
The device's analog dimming mode is achieved by changing the internal reference voltage proportional to the
voltage level of the analog input in 5% to 100% range. TPS92200D2 implement deeper analog dimming by
changing the internal reference voltage proportional to the duty cycle of the PWM signal input in 1% to 100%
range.
For safety and protection, the TPS92200 devices implement full protections include LED open, LED+ short-to-
GND, LED short, sense resistor open and short, and device thermal protection. Hiccup mode is triggered at
current limit or FB pin overvoltage scenario to avoid the device overheats.
7.2 Functional Block Diagram
BOOT
IN
HS Driver
HS
HS
TSD
Current Sense
Current Limit
Device
Slope
ON/OFF
Compensation
DIM
Dimming
Control
PWM Comparator
Error Amplifier
SW
VREF
PWM
Control
Over Current Protection
Auto-retry
Mode
FB
VFB_OVP
Oscillator
LS Driver
LS
Current Limit
GND
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7.3 Feature Description
7.3.1 Peak-Current-Mode PWM Control
The TPS92200 device uses peak-current-mode control and full internal compensation to provide high transient
response performance over a wide range of operating conditions. The switching frequency is internally set to 1
MHz when the minimum off time tMIN_OFF is not triggered, thus minimizing the external inductor and capacitor
size.
During each switching cycle, when the high-side power switch is turned on, the load current is sensed through
the external sense resistor, RSENSE. The sensed voltage on the FB pin is compared with the internal voltage
reference, VREF, through the error amplifier. The output of the error amplifier, VCOMP, is compared with the real-
time current, IHS_SENSE, going through the high-side power switch. Slope compensation circuitry is implemented
in the device to prevent sub-harmonic oscillations as the duty cycle increases in peak-current-control mode.
When the peak value of VHS_SENSE reaches VCOMP in the PWM comparator, the high-side power switch is turned
off and the low-side NMOS is turned on at the same time. The low-side power switch stays turned on until the
end of the PWM cycle. Thus, by regulating the real-time peak current in each switching cycle, the device controls
the load current at the target value.
Error Amplifier
FB
PWM Comparator
VCOMP
+
VREF
+
PWM
VHS_SENSE
IHS_SENSE
ISLOPE
Figure 7-1. Error Amplifier and PWM Comparator
7.3.2 Setting LED Current
The LED current is set by the external resistor between the LEDs cathode and GND. Because the FB pin voltage
reference VFB_REF is fixed at 99 mV, the sensing resistor can be calculated using Equation 1.
VFB _REF
=
RSENSE
ILED
(1)
7.3.3 Internal Soft Start
The TPS92200 device implements the internal soft-start function. The VREF ramps smoothly during the soft-start
period. The internal soft-start period is set as tSS, 0.5 ms typically.
7.3.4 Input Undervoltage Lockout
The device implements internal Undervoltage Lockout (UVLO) circuitry on the IN pin. The device is disabled
when the IN pin voltage falls below the internal IN UVLO threshold, 3.5-V typical. The internal IN UVLO threshold
has a hysteresis of 0.2-V typical.
7.3.5 Bootstrap Regulator
The TPS92200 integrates a bootstrap regulator inside, and requires an external capacitor between the BOOT
and SW pins to provide the gate driver voltage for the high-side power switch. TI recommends a 0.1-µF ceramic
capacitor with an X7R or X5R dielectric because of the stable characteristics over temperature and voltage.
7.3.6 Maximum Duty Cycle
For a buck LED driver, the maximum duty cycle is limited by the minimum off time tMIN_OFF and switching
frequency. To achieve the maximum brightness when the input voltage is close to output voltage, the TPS92200
device has a mechanism to decrease the switching frequency. This mechanism extends the on-time up to
tMAX_ON, 6.6 µs (typical). With this function, the TPS92200 device maximum duty cycle is able to go up to DMAX
,
99% (typical).
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7.3.7 Overcurrent Protection
The device is protected from overcurrent conditions by cycle-by-cycle current limiting on both the high-side
NMOS and the low-side NMOS.
7.3.7.1 High-Side MOSFET Overcurrent Protection
During each switching on cycle, the high-side sense voltage, VHS_SENSE, is compared with VCOMP to generate
the PWM duty cycle. In order to prevent an overcurrent stress, VCOMP is internally clamped to set the high-side
NMOS current limit as ILIM_HS. When the peak of IHS_SENSE exceeds ILIM_HS, the high-side MOSFET is turned
off and the low-side MOSFET is turned on accordingly. An auto-retry mechanism is implemented for this case, if
an output overcurrent condition occurs for more than auto-retry on time tRETRY_ON, which is programmed for 512
switching cycles, the device shuts down for an auto-retry off-time tRETRY_OFF, which is 60 ms typically.
7.3.7.2 Low-Side MOSFET Sourcing Overcurrent Protection
During each switching off-cycle, the low-side MOSFET is turned on and the conduction current is monitored by
the internal circuitry. At the end of every clock cycle, the low-side MOSFET sourcing current is compared to the
internally set low-side sourcing-current limit, ILIM_LS_SOUR. If the low-side sourcing-current limit is exceeded, the
high-side MOSFET does not turn on and the low-side MOSFET stays on for the next clock cycle. The high-side
MOSFET turns on again when the low-side current is below the low-side sourcing current limit at the start of a
cycle.
7.3.7.3 Low-Side MOSFET Sinking Overcurrent Protection
During each switching off-cycle, the device also monitors the sinking current of the low-side MOSFET by
detecting the voltage across it and setting a sinking overcurrent limit, ILIM_LS_SINK, to protect the low-side power
switch from overstress. When the peak of the sinking current reaches ILIM_LS_SINK, both the high-side MOSFET
and low-side MOSFET are turned off. The high-side MOSFET turns on again when the low-side current is below
the low side sinking current-limit at the start of a new cycle.
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7.3.8 Fault Protection
The device is protected from several kinds of fault conditions, such as LED open and short, sense resistor open
and short, and thermal shutdown.
Table 7-1. Protections
TYPE
CRITERION
BEHAVIOR
LED open load
VFB close to 0 mV
The device keeps maximum duty cycle turn-on.
When VFB > VFB_OVP , the device keeps the
minimum on-time, and starts the auto-retry
timer. During the auto-retry mode, the device is
protected by the overcurrent limits.
LED+ and LED– short circuit
VFB > VFB_OVP
When the high-side or low-side MOSFET current
limit is triggered, the device starts the auto-retry
timer.
High-side or low-side NMOS current limit
triggered
LED+ short-to-GND
Sense-resistor open load
When VFB > VFB_OVP , the device keeps the
minimum on-time, and starts the auto-retry timer.
VFB > VFB_OVP
When the high-side or low-side MOSFET current
limit is triggered, the device starts the auto-retry
timer.
High-side or low-side MOSFET current limit
triggered
Sense-resistor short circuit to GND
Disable the device when TJ>TTSD, re-activate
the device when TJ falls below the hysteresis
level.
Thermal shutdown
TJ > TTSD
7.3.8.1 LED Open-Load Protection
When LED load is open, VFB voltage is low. The internal error amplifier output voltage, VCOMP, is driven high and
clamped. The high-side MOSFET is forced to turn on with the maximum PWM duty cycle, DMAX
.
7.3.8.2 LED+ and LED– Short Circuit Protection
When LED+ and LED– are shorted, VFB is higher than internal reference voltage, VREF, and internal error
amplifier output voltage VCOMP is driven low and clamped. The high-side MOSFET is forced to turn on with
the minimum on-time each cycle, tMIN_ON. In this case, if the output voltage is too low, the inductor current
cannot balance in a cycle, causing current runaway. Finally, the inductor current is clamped by low-side
MOSFET sourcing current limit ILIM_LS_SOUR which is 3-A typical. If VFB rises higher than VFB_OVP, the device
starts the auto-retry timer. Once the counter, tRETRY_ON, expires, the device shuts down and starts another
counter, tRETRY_OFF. During the shutdown period, both high-side and low-side MOSFETs are turned off. Once
the hiccup timer expires, TPS92200 restarts again. The device repeats these behaviors until the failure condition
is removed. During the auto-retry mode, the device is also protected by the overcurrent limits of both high-side
power switch and low-side power switch.
7.3.8.3 LED+ Short Circuit to GND Protection
When LED+ is shorted to GND, VFB is low and VCOMP is driven high and clamped. The high-side MOSFET
is forced to turn on with maximum PWM duty cycle, once either the high-side or low-side overcurrent limit is
triggered, the device starts the auto-retry counter. When the counter tRETRY_ON expires, the device shuts down
and starts another counter tRETRY_OFF. During the shutdown period, both high-side and low-side NMOSs are
switched off. The device repeats these actions until the failure condition is removed.
7.3.8.4 Sense-Resistor Open-Load Protection
When the RSENSE load is open, VFB is higher than VREF, and VCOMP is driven low and clamped. The high-side
NMOS is forced to turn on with the minimum on-time each cycle, tMIN_ON. If VFB rises higher than VFB_OVP
,
the device starts the auto-retry timer. Once the counter tRETRY_ON expires, the device shuts down and starts
another counter tRETRY_OFF. During the shutdown period, both high-side and low-side NMOSs are switched off.
The device repeats these actions until the failure condition is removed. To prevent the FB pin from overvoltage
damage during the tRETRY_ON period, the FB pin implements a comparator with a 1-V threshold. If VFB > 1 V,
both high-side and low-side NMOSs are switched off immediately and the tRETRY_OFF counter starts.
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7.3.8.5 Sense Resistor Short Circuit-to-GND Protection
When RSENSE is shorted to GND, VFB is low and VCOMP is driven high and clamped. Once the current reaches
either the high-side overcurrent limit or low-side overcurrent limit, the device starts the auto-retry counter.
Once the tRETRY_ON counter expires, the device shuts down and starts another counter, tRETRY_OFF. During the
shutdown period, both high-side and low-side NMOSs are switched off. The device repeats these actions until
the failure condition is removed.
7.3.8.6 Overvoltage Protection
When the FB pin, for some reason, has a voltage higher than 1-V applied, the device shuts down immediately.
Both high-side and low-side MOSFETs are kept off, and the device starts the auto-retry counter, tRETRY_OFF
.
When the counter tRETRY_OFF expires, the device restarts again. If the failure still exists, TPS92200 repeats
above hiccup shutdown and restart process.
7.3.8.7 Thermal Shutdown
The TPS92200 device implements a thermal shutdown mechanism to protect the device from damage due to
overheating. When the junction temperature rises to 160°C (typical), the device shuts down immediately. The
TPS92200 device releases thermal shutdown when the junction temperature of the device is reduced to 145°C
(typical).
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7.4 Device Functional Modes
Table 7-2. Functional Modes
DIM Pin
Constant High
DIM Pin
Constant Low
Device Name
Dimming Input Type
Dimming Output Type
Digital signal
•
•
Amplitude: VH > 1.4 V and VL < 0.3 V
Frequency: 100 Hz–2 kHz
PWM Dimming
TPS92200D1
TPS92200D2
Analog voltage
Device full on
Device turned off
5%–100% Analog Dimming
1%–100% Analog Dimming
•
•
Amplitude: 0.65 V–1.2 V
Digital signal
Frequency: 20 kHz–200 kHz
7.4.1 Enable and Disable the Device
The DIM pin performs not only the dimming function, but also the enable-and-disable function. When the VIN
voltage is above the UVLO threshold, the TPS92200 device can be enabled by driving the DIM pin higher than
the threshold voltage VDIM_H for a period longer than tDIM_ON1. To disable the device, the DIM pin must be kept
lower than the threshold voltage VDIM_L for a period longer than tDIM_OFF. External pulldown is required to set the
device as default-disabled, because the DIM pin is designed as a high-impedance input.
7.4.2 TPS92200D1 PWM Dimming
For the TPS92200D1 version, when applying a digital signal on the DIM pin, the device enters into PWM
dimming mode. The amplitude of the digital signal must be higher than 1.4 V for high level and less than 0.3
V for low level, which is out of the analog dimming range (0.65 V–1.2 V). TI recommends the frequency of the
digital signal be from 100 Hz to 2 kHz to achieve good dimming accuracy. In PWM dimming mode, the output
turns on and off simultaneously with the digital-input high and low pulses, respectively.
Output Duty
100%
PWM Duty
0%
0%
100%
Figure 7-2. TPS92200D1 PWM Dimming
7.4.3 TPS92200D1 Analog Dimming
For the TPS92200D1 version, when applying an analog voltage on the DIM pin and the amplitude is between
0.65 V and 1.2 V, the device enters into analog dimming mode, and the reference voltage VREF is changed
proportionally to the analog input level. When VDIM = 0.65 V, the reference voltage is 5 mV. When VDIM = 1.2 V,
the reference voltage is 99 mV.
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VFB
99mV
VDIM
Figure 7-3. TPS92200D1 Analog Dimming
7.4.4 TPS92200D2 Analog Dimming
5mV
0.65V
1.2V
The TPS92200D2 version supports accurate analog dimming with a digital signal. When applying a digital signal
on the DIM pin, the device enters into analog dimming mode, and the reference voltage VREF is changed
proportionally to the duty cycle of digital input. The frequency of the digital signal must be within the range of 20
kHz to 200 kHz.
VFB
99mV
PWM Duty
0mV
0%
100%
Figure 7-4. TPS92200D2 Analog Dimming
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8 Application and Implementation
Note
Information in the following applications sections is not part of the TI component specification,
and TI does not warrant its accuracy or completeness. TI’s customers are responsible for
determining suitability of components for their purposes, as well as validating and testing their design
implementation to confirm system functionality.
8.1 Application Information
The TPS92200 device is typically used as a buck converter to drive one or more LEDs from a 4-V to 30-V input.
8.2 Typical Application
8.2.1 TPS92200D1 12-V Input, 1.5-A, 2-Piece IR LED Driver With Analog Dimming
Figure 8-1. 12-VIN, 1.5-A, 2-piece IR LED, Analog Dimming Reference Design
8.2.1.1 Design Requirements
For this design example, use the parameters in the following table.
Table 8-1. Design Parameters
PARAMETER
Input voltage range
LED forward voltage
Output voltage
VALUE
12 V ±10%
1.75 V
3.6 V (1.75 × 2 + 0.1)
1.5 A
Maximum LED current
Inductor current ripple
LED current ripple
Input voltage ripple
30% of maximum LED current
20 mA or less
200 mV or less
Analog dimming with TPS92200D1: 0.65-V to 1.2-V analog input on
DIM pin
Dimming type
8.2.1.2 Detailed Design Procedure
8.2.1.2.1 Inductor Selection
Use Equation 2 to calculate the recommended value of the output inductor L.
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k
8176 × 88+0(max ) F 8176
o
L =
88+0(max ) × -
× +.'& × B
59
+0&
(2)
where
•
KIND is a coefficient that represents the amount of inductor ripple current relative to the maximum LED
current.
•
•
ILED is the maximum LED current.
VOUT is the sum of the voltage across the LED load and the voltage across the sense resistor.
In general, the value of KIND is suggested between 0.2 and 0.4. For the application that can tolerate higher LED
current ripple or use larger output capacitors, one can choose 0.4 for KIND, otherwise, smaller KIND like 0.2 can
be chosen to get smaller LED current ripple.
With the chosen inductor value, the user can calculate the actual inductor current ripple using Equation 3.
k
8176 × 88+0(max ) F 8176
o
+
=
.(NELLHA )
88+0(max ) × . × B
59
(3)
For TPS92200, TI suggests that the inductor current ripple be larger than 300 mA to assure loop stability. If the
calculated inductor current ripple is less than 300 mA, TI suggests a smaller inductor.
The inductor RMS current and saturation-current ratings must be greater than those seen in the application.
These ratings ensure that the inductor does not overheat or saturate. During power up, transient conditions,
or fault conditions, the inductor current can exceed its normal operating current. For this reason, the most
conservative approach is to specify an inductor with a saturation current rating equal to or greater than the
converter current limit. This action is not always possible due to application size limitations. The peak-inductor-
current and RMS current equations are shown in Equation 4 and Equation 5.
IL(ripple)
IL(peak) = ILED
+
2
(4)
2
IL(ripple)
2
IL(rms)
=
ILED
+
12
(5)
In this design, VIN(max) = 13.2 V, VOUT = 3.6 V, ILED = 1.5 A, choose KIND = 0.3, the calculated inductance is
5.8-µH. A 4.7-µH inductor is chosen. With this inductor, the ripple, peak, and RMS currents of the inductor are
0.56 A, 1.78 A and 1.51 A respectively. The chosen inductor has ample margin.
8.2.1.2.2 Input Capacitor Selection
The device requires an input capacitor to reduce the surge current drawn from the input supply and the switching
noise from the device. Ceramic capacitors with X5R or X7R dielectrics are highly recommended because of their
low ESR and small temperature coefficients. For most applications, a 10-μF capacitor with an additional 0.1-µF
capacitor from VIN to GND to provide additional high-frequency filtering is enough. The input capacitor voltage
rating must be greater than the maximum input voltage.
In this design, a 10-µF, 35-V X7R ceramic capacitor is chosen. This yields around 40-mV input ripple voltage.
8.2.1.2.3 Output Capacitor Selection
The output capacitor reduces the high-frequency ripple current through the LED string. Various guidelines
disclose how much high-frequency ripple current is acceptable in the LED string. Excessive ripple current in the
LED string increases the RMS current in the LED string, and therefore the LED temperature also increases.
1. Calculate the total dynamic resistance of the LED string (RLED) using the LED manufacturer's data sheet.
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2. Calculate the required impedance of the output capacitor (ZOUT) given the acceptable peak-to-peak ripple
current through the LED string, ILED(ripple) × IL(ripple), is the peak-to-peak inductor ripple current as calculated
previously in inductor selection.
3. Calculate the minimum effective output capacitance required.
4. Increase the output capacitance appropriately due to the derating effect of applied dc voltage.
See Equation 6, Equation 7, and Equation 8.
¿8(
4.'&
=
× # KB .'&O
¿+(
(6)
(4.'& + 45'05' ) × +.'&(NELLHA )
<
%176
=
+.(NELLHA ) F +.'&(NELLHA )
(7)
(8)
1
%
176
=
2è × B × <%176
59
Once the output capacitor is chosen, Equation 9 can be used to estimate the peak-to-peak ripple current through
the LED string.
<
× +.(NELLHA )
%176
+
=
.'&(NELLHA )
<
+ 4.'& + 45'05'
%176
(9)
OSRAM SFH4715A IR LED is used here. The dynamic resistance of this LED is 0.29 ohm at 1.5-A forward
current. Ceramic capacitors with X5R or X7R dielectrics are highly recommended because of their low ESR and
small temperature coefficients. In this design, a 10-µF, 35-V X7R ceramic capacitor is chosen, the part number is
GRM32ER7YA106KA12L. The calculated ripple current of the LED is about 23.8 mA.
8.2.1.2.3.1 Sense Resistor Selection
The maximum LED current is 1.5 A at 100% PWM duty and the corresponding VREF is 99 mV. By using Equation
1, calculate the needed sense resistance at 66 mΩ. Pay close attention to the power consumption of the sense
resistor in this design at 148.5 mW, and make sure the chosen resistor has enough margin in its power rating.
8.2.1.2.3.1.1 Other External Components Selection
In this design, a 0.1-µF, 50-V X7R ceramic capacitor is chosen for CBOOT
.
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8.2.1.3 Application Curves
Blue: SW, Red: Inductor Current, Green: LED Current Ripple
(AC)
Blue: SW, Red: Inductor Current, Green: LED Current Ripple
(AC)
Figure 8-2. LED Current Ripple at VDIM = 0.65 V
Figure 8-3. LED Current Ripple at VDIM = 1.2 V
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Figure 8-4. LED Current Transient for a VDIM
Transition From 0.65 V to 1.2 V
Figure 8-5. LED Current Transient for a VDIM
Transition From 1.2 V to 0.65 V
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Figure 8-6. Start-Up at VDIM = 1.2 V
Figure 8-7. Shutdown at VDIM = 1.2 V
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Black: Vout, Blue: SW, Green: LED Current, Orange: Inductor
Current
Black: Vout, Blue: SW, Green: LED Current, Orange: Inductor
Current
Figure 8-8. LED Open-Load Protection
Figure 8-9. LED+ Short-to-GND Protection
Black: Vout, Blue: SW, Green: LED Current, Orange: Inductor
Current
Black: Vout, Blue: SW, Green: LED Current, Orange: Inductor
Current
Figure 8-10. LED+ and LED– Short Circuit-
Figure 8-11. Sense-Resistor Open-Load Protection
Black: Vout, Blue: SW, Green: LED Current, Orange: Inductor Current
Figure 8-12. Sense-Resistor Short-to-GND Protection
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8.2.2 TPS92200D1 24-V Input, 1-A, 6-Piece WLED Driver With PWM Dimming
Figure 8-13. 24-VIN, 1-A, 6-piece WLED, PWM Dimming Reference Design
8.2.2.1 Design Requirements
For this design example, use the parameters in the following table.
Table 8-2. Design Parameters
PARAMETER
Input voltage range
LED forward voltage
Output voltage
VALUE
24 V ±10%
3 V
18.1 V (3 × 6 + 0.1)
1 A
Maximum LED current
Inductor current ripple
LED current ripple
Input voltage ripple
60% of maximum LED current
20 mA or less
200 mV or less
PWM dimming with TPS92200D1: 500 Hz, 1% to 100% duty cycle
input on the DIM pin
Dimming type
8.2.2.2 Detailed Design Procedure
8.2.2.2.1 Inductor Selection
For this application, input voltage is 24-V rail with 10% variation, output is 6 white LEDs in series and the
inductor current ripple requirement is less than 60% of maximum LED current. To choose a proper peak-to-peak
inductor current ripple, the low-side FET sink current limit must not be violated when the converter works in
no-load condition. This action requires the half of peak-to-peak inductor current ripple to be lower than that limit.
Another consideration is the increased core loss and copper loss in the inductor with this larger peak-to-peak
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current ripple which is also acceptable. Once this peak-to-peak inductor current ripple is chosen, use Equation
10 to calculate the recommended value of the output inductor L.
k
8176 × 88+0(max ) F 8176
o
L =
88+0(max ) × -
× +.'& × B
59
+0&
(10)
where
•
KIND is a coefficient that represents the amount of inductor ripple current relative to the maximum LED
current.
•
•
ILED is the maximum LED current.
VOUT is the sum of the voltage across LED load and the voltage across sense resistor.
With the chosen inductor value, the user can calculate the actual inductor-current ripple using Equation 11.
k
8176 × 88+0(max ) F 8176
o
+
=
.(NELLHA )
88+0(max ) × . × B
59
(11)
In this design, VIN(max) = 26.4 V, VOUT = 18.1 V, ILED = 1 A, choose KIND = 0.6, the calculated inductance is 9.49
µH. A 10-µH inductor is chosen. With this inductor, the ripple, peak, and rms currents of the inductor are 0.57 A,
1.29 A, and 1.01 A, respectively.
8.2.2.2.2 Input Capacitor Selection
In this design, a 10-µF, 35-V X7R ceramic capacitor, part number GRM32ER7YA106KA12L, from muRata is
chosen. This ceramic capacitor yields around 30-mV input-ripple voltage.
8.2.2.2.3 Output Capacitor Selection
The dynamic resistance of this Cree white LED is 0.67 ohm at 1-A forward current. In this design, choose a
10-µF, 35-V X7R ceramic capacitor, part number GRM32ER7YA106KA12L. The calculated ripple current of LED
is about 11.5mA.
8.2.2.2.3.1 Sense Resistor Selection
The maximum LED current is 1 A, and the corresponding VREF is 99 mV. Using Equation 1, calculate the needed
sense resistance at 99 mΩ. Pay close attention to the power consumption of the sense resistor in this design at
99 mW, and make sure the chosen resistor has enough margin in its power rating.
8.2.2.2.3.1.1 Other External Components Selection
See the Other External Components Selection.
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8.2.2.3 Application Curves
Blue: SW, Red: Inductor Current, Green: LED Current Ripple
(AC)
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Figure 8-15. LED Current Transient From 1% to
100% Duty Cycle at 500 Hz
Figure 8-14. LED Current Ripple at 100% Duty
Cycle and 500 Hz
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Figure 8-17. Start-Up at 1% Duty Cycle and 500 Hz
Figure 8-16. LED Current Transient From 100% to
1% Duty Cycle at 500 Hz
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Figure 8-18. Shutdown at 1% Duty Cycle and 500
Hz
Figure 8-19. Start-Up at 100% Duty Cycle and 500
Hz
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Black: DIM, Blue: SW, Red: Inductor Current, Green: LED
Current
Figure 8-20. Shutdown at 100% Duty Cycle and 500
Hz
Figure 8-21. LED PWM Dimming at 1% Duty Cycle
and 200 Hz
Black: DIM, Blue: SW, Red: Inductor Current, Green: LED
Current
Black: DIM, Blue: SW, Red: Inductor Current, Green: LED
Current
Figure 8-22. LED PWM Dimming at 50% Duty Cycle
and 200 Hz
Figure 8-23. LED PWM Dimming at 99% Duty Cycle
and 200 Hz
Black: DIM, Blue: SW, Red: Inductor Current, Green: LED
Current
Black: DIM, Blue: SW, Red: Inductor Current, Green: LED
Current
Figure 8-25. LED PWM Dimming at 99% Duty Cycle
and 2 kHz
Figure 8-24. LED PWM Dimming at 50% Duty Cycle
and 2 kHz
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8.2.3 5-V Input, 1-A, 1-Piece IR LED Driver With TPS92200D2
Figure 8-26. 5-VIN, 1-A, 1-piece IR LED, Analog Dimming Reference Design
8.2.3.1 Design Requirements
For this design example, use the parameters in the below table.
Table 8-3. Design Parameters
PARAMETER
Input voltage range
LED forward voltage
Output voltage
VALUE
5 V ±10%
1.75 V
1.85 V (1.75 + 0.1)
1 A
Maximum LED current
Inductor current ripple
LED current ripple
Input voltage ripple
60% of maximum LED current
20 mA or less
200 mV or less
Analog dimming with TPS92200D2: 50 kHz, 1% to 100 % duty cycle
input on the DIM pin
Dimming type
8.2.3.2 Detailed Design Procedure
8.2.3.2.1 Inductor Selection
For this application, input voltage is 5-V rail with 10% variation, output is a single IR LED, and the inductor
current ripple requirement is less than 60% of maximum LED current.
Use Equation 12 to calculate the minimum value of the output inductor (LMIN).
k
8176 × 88+0(max ) F 8176
o
L =
88+0(max ) × -
× +.'& × B
59
+0&
(12)
where
•
KIND is a coefficient that represents the amount of inductor ripple current relative to the maximum LED
current.
•
•
ILED is the maximum LED current.
VOUT is the sum of the voltage across LED load and the voltage across sense resistor.
With the chosen inductor value, the user can calculate the actual inductor current ripple using Equation 13.
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k
8176 × 88+0(max ) F 8176
o
+
=
.(NELLHA )
88+0(max ) × . × B
59
(13)
In this design, VIN(max) = 5.5 V, VOUT = 1.85 V, ILED = 1 A, choose KIND = 0.6. The calculated inductance is 2.046
µH. A 2.2-µH inductor is chosen. With this inductor, the ripple, peak, and RMS currents of the inductor are 0.56
A, 1.28 A, and 1.01 A, respectively.
8.2.3.2.2 Input Capacitor Selection
In this design, a 10-µF, 35-V X7R ceramic capacitor, part number GRM32ER7YA106KA12L, from muRata is
chosen. This ceramic capacitor yields around 30-mV input ripple voltage.
8.2.3.2.3 Output Capacitor Selection
The dynamic resistance of this LED is 0.29 ohm at 1-A forward current. In this design, choose a 10-µF, 35-V
X7R ceramic capacitor, part number GRM32ER7YA106KA12. The calculated ripple current of LED is about 21.9
mA.
8.2.3.2.3.1 Sense Resistor Selection
The maximum LED current is 1 A, and the corresponding VREF is 99 mV. Using Equation 1, calculate the needed
sense resistance at 99 mΩ. Pay close attention to the power consumption of the sense resistor in this design at
99 mW, and make sure the chosen resistor has enough margin in its power rating.
8.2.3.2.3.1.1 Other External Components Selection
See the Other External Components Selection section.
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8.2.3.3 Application Curves
Blue: SW, Red: Inductor Current, Green: LED Current Ripple
(AC)
Blue: SW, Red: Inductor Current, Green: LED Current Ripple
(AC)
Figure 8-27. LED Current Ripple at 1% Duty Cycle
and 50 kHz
Figure 8-28. LED Current Ripple at 100% Duty
Cycle and 50 kHz
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Black: DIM, Blue: SW, Red: FB, Green: LED Current
Figure 8-29. LED Current Transient From 1% to
100% Duty Cycle at 50 kHz
Figure 8-30. LED Current Transient From 100% to
1% Duty Cycle at 50 kHz
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Black: DIM, Blue: SW, Red: VOUT, Green: LED Current
Figure 8-31. Start-Up at 100% Duty Cycle and 50
kHz
Figure 8-32. Shutdown at 100% Duty Cycle and 50
kHz
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Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Figure 8-33. LED Analog Dimming at 1% Duty
Figure 8-34. LED Analog Dimming at 50% Duty
Cycle d 20 kHz
Cycle and 20 kHz
Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Figure 8-35. LED Analog Dimming at 99% Duty
Cycle and 20 kHz
Figure 8-36. LED Analog Dimming at 1% Duty
Cycle and 200 kHz
Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Black: DIM, Blue: SW, Orange: Inductor Current, Green: LED
Current
Figure 8-37. LED Analog Dimming at 50% Duty
Cycle and 200 kHz
Figure 8-38. LED Analog Dimming at 99% Duty
Cycle and 200 kHz
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9 Power Supply Recommendations
The devices are designed to operate from an input voltage supply range between 4 V and 30 V. This input
supply must be well regulated. The device requires an input capacitor to reduce the surge current drawn from
the input supply and the switching noise from the device. Ceramic capacitors with X5R or X7R dielectrics are
highly recommended because of their low ESR and small temperature coefficients. For most applications, a
10-μF capacitor is enough.
10 Layout
The TPS92200 device requires a proper layout for optimal performance. The following section gives some
guidelines to ensure a proper layout.
10.1 Layout Guidelines
An example of a proper layout for the TPS92200 device is shown in Figure 10-1.
•
•
Creating a large GND plane for good electrical and thermal performance is important.
The IN and GND traces must be as wide as possible to reduce trace impedance. Wide traces have the
additional advantage of providing excellent heat dissipation.
•
Thermal vias can be used to connect the top-side GND plane to additional printed-circuit board (PCB) layers
for heat dissipation and grounding.
•
•
•
•
The input capacitors must be located as close as possible to the IN pin and the GND pin.
The SW trace must be kept as short as possible to reduce radiated noise and EMI.
Do not allow switching current to flow under the device.
The FB trace must be kept as short as possible and placed away from the high-voltage switching trace and
the ground shield.
•
In higher-current applications, routing the load current of the current-sense resistor to the junction of the input
capacitor and GND node can be necessary.
10.2 Layout Example
COUT
OUT
SENSE
L
RFB
RSENSE
FB
BOOT
CBOOT
SW
SW
DIM
GND
TPS92200
IN
GND
IN
CIN
Figure 10-1. DDC Package Layout Example
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OUT
SENSE
COUT
L
RSENSE
RFB
CBOOT
BOOT
FB
SW
DIM
SW
VIN
GND
GND
IN
CIN
Figure 10-2. RXL Package Layout Example
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11 Device and Documentation Support
11.1 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on
Subscribe to updates to register and receive a weekly digest of any product information that has changed. For
change details, review the revision history included in any revised document.
11.2 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is provided "AS IS" by the respective contributors. They do not constitute TI specifications and do
not necessarily reflect TI's views; see TI's Terms of Use.
11.3 Trademarks
TI E2E™ is a trademark of Texas Instruments.
All trademarks are the property of their respective owners.
11.4 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric changes could cause the device not to meet its published
specifications.
11.5 Glossary
TI Glossary
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most-
current data available for the designated devices. This data is subject to change without notice and without
revision of this document. For browser-based versions of this data sheet, see the left-hand navigation pane.
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EXAMPLE BOARD LAYOUT
RXL0006A
VQFN-HR - 1 mm max height
PLASTIC SMALL OUTLINE - NO LEAD
(0.05)
(1)
(0.2)
2X (0.7)
6
1
(0.2)
(0.7)
(0.775)
(0.275)
PKG
(0.05)
2X (0.75)
6X (0.2)
3
4
(0.6)
3X (0.6)
(R0.05) TYP
(0.65)
2X (0.65)
PKG
LAND PATTERN EXAMPLE
SCALE:40X
0.05 MIN
ALL AROUND
0.05 MAX
ALL AROUND
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
METAL
SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
SOLDER MASK
DEFINED
SOLDER MASK DETAILS
4226620/A 04/2021
NOTES: (continued)
3. For more information, see Texas Instruments literature number SLUA271 (www.ti.com/lit/slua271).
www.ti.com
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PACKAGE OPTION ADDENDUM
www.ti.com
17-Nov-2021
PACKAGING INFORMATION
Orderable Device
Status Package Type Package Pins Package
Eco Plan
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
Samples
Drawing
Qty
(1)
(2)
(3)
(4/5)
(6)
PTPS92200D2RXLR
TPS92200D1DDCR
TPS92200D2DDCR
ACTIVE
VQFN-HR
RXL
DDC
DDC
6
6
6
3000
TBD
Call TI
Call TI
-40 to 85
-40 to 85
-40 to 85
ACTIVE SOT-23-THIN
ACTIVE SOT-23-THIN
3000 RoHS & Green
3000 RoHS & Green
SN
SN
Level-1-260C-UNLIM
Level-1-260C-UNLIM
1SZK
1T1K
(1) The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6)
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two
lines if the finish value exceeds the maximum column width.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
17-Nov-2021
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 2
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Aug-2021
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
B0
K0
P1
W
Pin1
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant
(mm) W1 (mm)
TPS92200D1DDCR
TPS92200D2DDCR
SOT-
23-THIN
DDC
DDC
6
6
3000
3000
180.0
9.5
3.17
3.1
1.1
4.0
8.0
Q3
SOT-
180.0
9.5
3.17
3.1
1.1
4.0
8.0
Q3
23-THIN
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
12-Aug-2021
*All dimensions are nominal
Device
Package Type Package Drawing Pins
SPQ
Length (mm) Width (mm) Height (mm)
TPS92200D1DDCR
TPS92200D2DDCR
SOT-23-THIN
SOT-23-THIN
DDC
DDC
6
6
3000
3000
184.0
184.0
184.0
184.0
19.0
19.0
Pack Materials-Page 2
PACKAGE OUTLINE
DDC0006A
SOT - 1.1 max height
S
C
A
L
E
4
.
0
0
0
SOT
3.05
2.55
1.100
0.847
1.75
1.45
0.1 C
B
A
PIN 1
INDEX AREA
1
6
4X 0.95
1.9
3.05
2.75
4
3
0.5
0.3
0.1
6X
TYP
0.0
0.2
C A B
C
0 -8 TYP
0.25
GAGE PLANE
SEATING PLANE
0.20
0.12
TYP
0.6
0.3
TYP
4214841/B 11/2020
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Reference JEDEC MO-193.
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EXAMPLE BOARD LAYOUT
DDC0006A
SOT - 1.1 max height
SOT
SYMM
6X (1.1)
1
6
6X (0.6)
SYMM
4X (0.95)
4
3
(R0.05) TYP
(2.7)
LAND PATTERN EXAMPLE
EXPLOSED METAL SHOWN
SCALE:15X
METAL UNDER
SOLDER MASK
SOLDER MASK
OPENING
SOLDER MASK
OPENING
METAL
EXPOSED METAL
EXPOSED METAL
0.07 MIN
ARROUND
0.07 MAX
ARROUND
NON SOLDER MASK
DEFINED
SOLDER MASK
DEFINED
SOLDERMASK DETAILS
4214841/B 11/2020
NOTES: (continued)
4. Publication IPC-7351 may have alternate designs.
5. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
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EXAMPLE STENCIL DESIGN
DDC0006A
SOT - 1.1 max height
SOT
SYMM
6X (1.1)
1
6
6X (0.6)
SYMM
4X(0.95)
4
3
(R0.05) TYP
(2.7)
SOLDER PASTE EXAMPLE
BASED ON 0.125 THICK STENCIL
SCALE:15X
4214841/B 11/2020
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
7. Board assembly site may have different recommendations for stencil design.
www.ti.com
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TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATA SHEETS), DESIGN RESOURCES (INCLUDING REFERENCE
DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES “AS IS”
AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY
IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD
PARTY INTELLECTUAL PROPERTY RIGHTS.
These resources are intended for skilled developers designing with TI products. You are solely responsible for (1) selecting the appropriate
TI products for your application, (2) designing, validating and testing your application, and (3) ensuring your application meets applicable
standards, and any other safety, security, regulatory or other requirements.
These resources are subject to change without notice. TI grants you permission to use these resources only for development of an
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is granted to any other TI intellectual property right or to any third party intellectual property right. TI disclaims responsibility for, and you
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TI objects to and rejects any additional or different terms you may have proposed. IMPORTANT NOTICE
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2021, Texas Instruments Incorporated
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