MAX1820ZEUB+T [MAXIM]
Switching Regulator, Current-mode, 1.55A, 1200kHz Switching Freq-Max, PDSO10, MICRO, SOP-10;
| 型号： | MAX1820ZEUB+T |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Switching Regulator, Current-mode, 1.55A, 1200kHz Switching Freq-Max, PDSO10, MICRO, SOP-10 开关 光电二极管 |
| 文件： | 总18页 (文件大小：766K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-2011; Rev 2; 7/02
WCDMA Cellular Phone 600mA
Buck Regulators
General Description
Features
The MAX1820/MAX1821 low-dropout, pulse-width-mod-
ulated (PWM) DC-DC buck regulators are optimized to
provide power to the power amplifier (PA) in WCDMA
cell phones; however, they may be applied in many
other applications where high efficiency is a priority. The
supply voltage range is from 2.6V to 5.5V, and the guar-
anteed output current is 600mA; 1MHz PWM switching
allows for small external components, while skip mode
reduces quiescent current to 180µA with light loads.
ꢀ Dynamically Adjustable Output from 0.4V to 3.4V
(MAX1820)
ꢀ Programmable Output from 1.25V to 5.5V
(MAX1821)
ꢀ SYNC to 13MHz External Clock (MAX1820X)
ꢀ SYNC to 19.8MHz External Clock (MAX1820Y)
ꢀ NO SYNC, Internal 1MHz Oscillator (MAX1820Z)
The MAX1820 is dynamically controlled to provide vary-
ing output voltages from 0.4V to 3.4V. The circuit is
designed such that the output voltage settles in <30µs
for a full-scale change in voltage and current. The
MAX1821 is set with external resistors to provide any
fixed output voltage in the 1.25V to 5.5V range.
ꢀ Low Quiescent Current
180µA (typ) in Skip Mode
0.1µA (typ) in Shutdown Mode
ꢀ No External Schottky Diode Required
ꢀ 600mA Guaranteed Output Current
ꢀ 0% to 100% Duty-Cycle Operation
The MAX1820/MAX1821 include a low on-resistance
internal MOSFET switch and synchronous rectifier to
maximize efficiency and minimize external component
count; 100% duty-cycle operation allows for low dropout
of only 150mV at 600mA load, including the external
inductor resistance. The devices are offered in 10-pin
ꢀ 150mV Dropout at 600mA Load (Including R
of External Inductor)
DC
ꢀ µMAX or UCSP Packaging
✕
µMAX and tiny 3 4 chip-scale (UCSP™) packages.
Typical Operating Circuits
________________________Applications
4.7µH
INPUT
2.6V TO
5.5V
DYNAMIC
OUTPUT
WCDMA Cell Phone Power Amplifiers
PDA, Palmtop, and Notebook Computers
Microprocessor Core Supplies
Digital Cameras
BATT
LX
0.4V TO 3.4V
OUT
SHDN
4.7µF
PGND
MAX1820
13MHz
OR
19.8MHz
PCMCIA and Network Cards
Hand-Held Instruments
COMP
GND
SYNC
V
OUT
CONTROL
DAC
REF
Typical Operating Circuits continued at end of data sheet.
Ordering Information continued at end of data sheet.
Pin Configurations appear at end of data sheet.
SKIP
UCSP is a trademark of Maxim Integrated Products, Inc.
Ordering Information
SYNC
PART
OUTPUT VOLTAGE
TEMP RANGE
PIN-PACKAGE
UCSP MARK
FREQ (MHz)
No Sync
19.8
✕
✕
✕
MAX1820ZEBC*
MAX1820YEBC*
MAX1820XEBC*
MAX1820ZEUB
MAX1820YEUB
MAX1820XEUB
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
Dynamic
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
3
3
3
4 UCSP
4 UCSP
4 UCSP
AAB
AAL
AAM
—
13
No Sync
19.8
10 µMAX
10 µMAX
10 µMAX
—
13
—
*UCSP reliability is integrally linked to the user’s assembly methods, circuit board material, and environment. Refer to the UCSP
Reliability Notice in the UCSP Reliability section of this data sheet for more information.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
WCDMA Cellular Phone 600mA
Buck Regulators
ABSOLUTE MAXIMUM RATINGS
BATT, OUT (FB), SHDN, SYNC, SKIP,
REF to GND.......................................................-0.3V to +6.0V
PGND to GND .......................................................-0.3V to +0.3V
LX, COMP to GND...................................-0.3V to (V
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Ranges
✕
3
4 UCSP ....................................................-40°C to +150°C
+ 0.3V)
BATT
10-Pin µMAX..................................................-65°C to +150°C
Solder Profile (UCSP) ......................................................(Note 1)
Lead Temperature (soldering, 10s) .................................+300°C
Output Short-Circuit Duration ............................................Infinite
Continuous Power Dissipation (T = +70°C)
A
✕
3
4 UCSP (derate 10.4mW/°C above +70°C)............832mW
10-Pin µMAX (derate 5.6mW/°C above +70°C)...........444mW
Note 1: For UCSP solder profile information, visit www.maxim-ic.com/1st_pages/UCSP.htm.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
BATT
(V
= 3.6V, SHDN = BATT, SKIP = SYNC = GND, V
= 1.25V (MAX1820 only), T = 0°C to +85°C, unless otherwise noted.
REF A
Typical values are at T = +25°C.) (Note 2)
A
PARAMETER
Input BATT Voltage
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
V
2.6
5.5
V
IN
Undervoltage Lockout
Threshold
V
V
rising, 1% hysteresis
BATT
2.20
2.35
2.55
V
UVLO
SKIP = GND (MAX1820Z/MAX1821)
SKIP = BATT, no switching
180
450
300
2000
Quiescent Current
I
µA
SKIP = GND (MAX1820Y, MAX1820X, and
MAX1821X)
Q
240
360
SKIP = BATT, 1MHz switching
SKIP = GND
3300
530
550
0.1
1000
1000
6
Quiescent Current in Dropout
µA
µA
SKIP = BATT, no switching
SHDN = GND
Shutdown Supply Current
I
SHDN
ERROR AMPLIFIER
V
= 1.932 0.005V, load = 0 to 600mA,
REF
3.33
0.35
250
3.4
0.40
400
0.1
3.47
0.45
SKIP = BATT or GND
OUT Voltage Accuracy
(MAX1820)
V
R
V
OUT
V
= 0.227 0.005V, load = 0 to 30mA,
REF
SKIP = BATT, V
≤ 4.2V
BATT
OUT Input Resistance
(MAX1820)
kΩ
µA
V
OUT
REF Input Current (MAX1820)
I
1
REF
FB Voltage Accuracy
(MAX1821)
V
FB = COMP
1.225
1.25
0.01
1.275
50
FB
FB Input Current (MAX1821)
I
V
= 1.4V
nA
FB
FB
Transconductance
g
30
0.2
50
85
1.0
µS
V
m
COMP Clamp Low Voltage
COMP Clamp High Voltage
0.45
2.15
2.04
2.28
V
2
_______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
ELECTRICAL CHARACTERISTICS (continued)
(V
= 3.6V, SHDN = BATT, SKIP = SYNC = GND, V = 1.25V (MAX1820 only), T = 0°C to +85°C, unless otherwise noted.
REF A
BATT
Typical values are at T = +25°C.) (Note 2)
A
PARAMETER
CONTROLLER
SYMBOL
CONDITIONS
MIN
TYP
MAX
0.3
UNITS
I
I
I
I
= 180mA, V
= 180mA, V
= 180mA, V
= 180mA, V
= 3.6V
= 2.6V
= 3.6V
= 2.6V
0.15
0.2
LX
LX
LX
LX
BATT
BATT
BATT
BATT
P-Channel On-Resistance
P
Ω
RDS
0.2
0.35
N-Channel On-Resistance
N
Ω
V/A
A
RDS
0.3
Current-Sense Transresistance
R
0.25
0.75
0.50
0.75
1.55
CS
P-Channel Current-Limit
Threshold
Duty factor = 100%
1.2
P-Channel Pulse-Skipping
Current Threshold
SKIP = GND
0.04
0.13
0.24
A
A
SKIP = BATT
SKIP = GND
-1.6
0.02
-1
-0.85
0.08
0.1
-0.45
0.14
1
N-Channel Current-Limit
Threshold
LX Leakage Current
Maximum Duty Cycle
I
V
= 5.5V, LX = GND or BATT
BATT
µA
%
LX
duty
100
MAX
SKIP = GND
0
Minimum Duty Cycle
duty
%
MIN
SKIP = BATT, V
= 4.2V
10
BATT
P-P
SYNC AND OSCILLATOR
SYNC = sine wave, SYNC input = 200mV
SYNC = sine wave, SYNC input = 800mV
13
13
13
13
P-P
SYNC Divide Ratio
(MAX1820X)
Hz/Hz
MHz
P-P
SYNC Capture Range
(MAX1820X)
SYNC = sine wave, AC-coupled,
10
-1
-5
13
16
+1
+5
SYNC input = 500mV
P-P
V
= 1V (MAX1820Z, MAX1821)
SYNC
SYNC Leakage Current
Frequency
I
µA
SYNC
V
= 1V (MAX1820X, MAX1820Y, and
SYNC
MAX1821X)
SYNC = sine wave, SYNC input = 200mV
SYNC = sine wave, SYNC input = 800mV
SYNC = sine wave, AC-coupled,
18
18
18
18
P-P
SYNC Divide Ratio
(MAX1820Y)
Hz/Hz
MHz
P-P
SYNC Capture Range
(MAX1820Y)
15
19.8
1
21
SYNC input = 500mV
P-P
Internal Oscillator Frequency
(MAX1820Z, MAX1821)
f
SYNC = GND
0.8
1.2
MHz
OSC
LOGIC INPUTS (SKIP, SHDN)
Logic Input High
V
1.6
-1
V
V
IH
Logic Input Low
V
0.4
1
IL
Logic Input Current
0.1
µA
_______________________________________________________________________________________
3
WCDMA Cellular Phone 600mA
Buck Regulators
ELECTRICAL CHARACTERISTICS
BATT
(V
= 3.6V, SHDN = BATT, SKIP = SYNC = GND, V
= 1.25V (MAX1820 only), T = -40°C to +85°C, unless otherwise noted.)
REF A
(Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
Input BATT Voltage
V
2.6
5.5
V
IN
Undervoltage Lockout
Threshold
V
V
rising, 1% hysteresis
BATT
2.15
2.55
300
360
V
UVLO
SKIP = GND (MAX1820Z, MAX1821)
SKIP = GND (MAX1820X, MAX1820Y, and
MAX1821X)
Quiescent Current
I
Q
µA
SKIP = BATT, no switching
SKIP = GND
2000
1000
1000
6
Quiescent Current in Dropout
µA
µA
SKIP = BATT, no switching
SHDN = GND
Shutdown Supply Current
I
SHDN
ERROR AMPLIFIER
V
= 1.932 0.005V, load = 0 to 600mA,
REF
3.33
0.35
250
3.47
0.45
SKIP = BATT or GND
OUT Voltage Accuracy
(MAX1820)
V
V
OUT
V
= 0.227 0.005V, load = 0 to 30mA,
REF
SKIP = BATT, V
≤ 4.2V
BATT
OUT Input Resistance
(MAX1820)
R
kΩ
µA
V
OUT
REF Input Current (MAX1820)
I
1
REF
FB Voltage Accuracy
(MAX1821)
V
FB = COMP
1.225
1.275
FB
FB Input Current (MAX1821)
I
FB
V
= 1.4V
50
nA
FB
Transconductance
g
30
0.2
85
1.0
µS
V
m
COMP Clamp Low Voltage
COMP Clamp High Voltage
CONTROLLER
2.04
2.28
V
P-Channel On-Resistance
N-Channel On-Resistance
Current-Sense Transresistance
P
I
I
= 180mA, V
= 180mA, V
= 3.6V
= 3.6V
0.3
Ω
Ω
RDS
RDS
LX
LX
BATT
N
0.35
0.75
BATT
R
0.25
0.75
V/A
CS
P-Channel Current-Limit
Threshold
Duty factor = 100%
1.55
0.24
A
A
A
P-Channel Pulse-Skipping
Current Threshold
SKIP = GND
0.04
SKIP = BATT
SKIP = GND
-1.6
-0.45
0.14
N-Channel Current-Limit
Threshold
0.01
4
_______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
ELECTRICAL CHARACTERISTICS (continued)
(V
BATT
= 3.6V, SHDN = BATT, SKIP = SYNC = GND, V = 1.25V (MAX1820 only), T = -40°C to +85°C, unless otherwise noted.)
REF A
(Notes 2, 3)
PARAMETER
SYMBOL
CONDITIONS
= 5.5V, LX = GND or BATT
BATT
MIN
-1
MAX
UNITS
µA
LX Leakage Current
Maximum Duty Cycle
I
V
1
LX
duty
100
%
MAX
SKIP = GND
0
Minimum Duty Cycle
duty
%
MIN
SKIP = BATT, V
= 4.2V
10
BATT
SYNC AND OSCILLATOR
SYNC = sine wave, SYNC input = 200mV
SYNC = sine wave, SYNC input = 800mV
13
13
13
13
P-P
SYNC Divide Ratio
(MAX1820X)
Hz/Hz
MHz
P-P
SYNC Capture Range
(MAX1820X)
SYNC = sine wave, AC-coupled,
10
16
SYNC input = 500mV
P-P
18
18
SYNC = sine wave, SYNC input = 200mV
SYNC = sine wave, SYNC input = 800mV
SYNC = sine wave, AC-coupled,
18
18
P-P
SYNC Divide Ratio
(MAX1820Y)
Hz/Hz
MHz
P-P
SYNC Capture Range
(MAX1820Y)
15
-1
-5
21
+1
SYNC input = 500mV
P-P
V
SYNC
= IV (MAX1820Z, MAX1821)
SYNC Leakage Current
I
µA
SYNC
V
SYNC
= IV (MAX1820X, MAX1820Y, and
+5
MAX1821X)
Internal Oscillator Frequency
(MAX1820Z, MAX1821)
f
SYNC = GND
0.8
1.6
1.2
MHz
OSC
LOGIC INPUTS (SKIP, SHDN)
Logic Input High
V
V
V
IH
Logic Input Low
V
0.4
1
IL
Logic Input Current
µA
Note 2: Limits are 100% production tested at T = +25°C for UCSP parts. Limits over the entire operating temperature range are
A
guaranteed by design and characterization but are not production tested.
Note 3: Specifications to -40°C are guaranteed by design and not subject to production test.
Typical Operating Characteristics
(T = +25°C, unless otherwise noted.)
A
EFFICIENCY vs. OUTPUT VOLTAGE
EFFICIENCY vs. INPUT VOLTAGE
NORMAL MODE, R = 10Ω
EFFICIENCY vs. OUTPUT VOLTAGE
(NORMAL MODE, V = 3.6V)
(PWM MODE, V = 3.6V)
IN
LOAD
IN
100
90
80
70
60
50
40
30
20
10
0
100
100
90
80
70
60
50
40
R = 5Ω
LOAD
R
LOAD
= 5Ω
90
80
70
60
50
40
V
= 3.4V
OUT
V
= 1.8V
OUT
R = 10Ω
LOAD
R
= 10Ω
LOAD
R = 15Ω
LOAD
R
= 15Ω
LOAD
V
= 0.4V
OUT
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
OUTPUT VOLTAGE (V)
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
(V)
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
OUTPUT VOLTAGE (V)
V
IN
_______________________________________________________________________________________
5
WCDMA Cellular Phone 600mA
Buck Regulators
Typical Operating Characteristics (continued)
(T = +25°C, unless otherwise noted.)
A
MAX1821 EFFICIENCY vs. LOAD CURRENT
MAX1821 EFFICIENCY vs. LOAD CURRENT
(V = 2.5V)
MAX1821 EFFICIENCY vs. LOAD CURRENT
(V = 1.5V)
(V
= 3.3V)
OUT
OUT
OUT
100
100
100
90
80
70
60
50
40
30
20
10
0
90
80
70
60
50
40
30
20
10
0
90
80
70
60
50
40
V
= 5.0V
V = 2.7V
IN
IN
V
= 3.6V
IN
V
= 3.6V
IN
V
= 3.6V
IN
V
= 5.0V
IN
V
= 2.7V
IN
V
= 2.7V
IN
V
= 3.6V
IN
V
= 3.6V
IN
V
= 5.0V
IN
V
= 5.0V
30
20
IN
V
= 5.0V
IN
SKIP = GND (DASHED LINE)
SKIP = BATT (SOLID LINE)
SKIP = GND (DASHED LINE)
SKIP = BATT (SOLID LINE)
SKIP = GND (DASHED LINE)
SKIP = BATT (SOLID LINE)
10
0
1
10
100
1000
1
10
100
1000
1
10
100
1000
LOAD CURRENT (mA)
LOAD CURRENT (mA)
LOAD CURRENT (mA)
DROPOUT VOLTAGE vs. LOAD CURRENT
SUPPLY CURRENT vs. SUPPLY VOLTAGE
SUPPLY CURRENT vs. SUPPLY VOLTAGE
140
120
100
80
9
8
7
6
5
4
3
2
1
0
220
200
180
160
140
120
100
80
60
40
60
V
= 3.4V
OUT
RL = 57mΩ
20
V
= 1.5V
V
= 1.5V
OUT
OUT
SKIP = BATT
40
SKIP = GND
0
20
0
100
200
300
400
500
600
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
SUPPLY VOLTAGE (V)
2.0 2.5 3.0 3.5
4.0 4.5 5.0 5.5
LOAD CURRENT (mA)
SUPPLY VOLTAGE (V)
HEAVY-LOAD SWITCHING WAVEFORMS
(V = 3.8V, V = 3.4V,
LIGHT-LOAD PWM SWITCHING WAVEFORMS
(V = 3.8V, V = 0.45V,
MEDIUM-LOAD SWITCHING WAVEFORMS
(V = 3.8V, V
= 1.8V,
IN
OUT
IN
OUT
IN
LOAD
OUT
I
= 600mA, SKIP = BATT)
I
= 30mA, SKIP = BATT)
LOAD
MAX1820/21 toc12
I
= 300mA, SKIP = BATT)
LOAD
MAX1820/21 toc10
MAX1820/21 toc11
A
B
A
A
B
B
C
C
C
400ns/div
400ns/div
400ns/div
A: V , 5V/div
A: V , 5V/div
LX
A: V , 5V/div
LX
LX
B: INDUCTOR CURRENT, 500mA/div
C: V (AC-COUPLED), 5mV/div
B: INDUCTOR CURRENT, 100mA/div
C: V (AC-COUPLED), 5mV/div
B: INDUCTOR CURRENT, 500mA/div
C: V (AC-COUPLED), 5mV/div
OUT
OUT
OUT
6
_______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
Typical Operating Characteristics (continued)
(T = +25°C, unless otherwise noted.)
A
LIGHT-LOAD SKIP-SWITCHING WAVEFORMS
(V = 4.2V, V = 1.5V,
EXITING AND ENTERING SHUTDOWN
IN
OUT
(V = 3.6V, V
= 3.4V, R
= 15Ω)
LOAD
MAX1820/21 toc14
IN
OUT
LOAD = 30mA, SKIP = GND)
MAX1820/21 toc13
V
SHDN
5V/div
A
B
V
OUT
2V/div
C
I
BATT
0.5A/div
2ms/div
2µs/div
A: V , 5V/div
LX
B: INDUCTOR CURRENT, 500mA/div
C: V (AC-COUPLED), 20mV/div
OUT
LOAD TRANSIENT (I
= 20mA TO 420mA,
LOAD TRANSIENT (I
= 20mA TO 420mA,
LOAD
LOAD
V
= 1.5V, V = 3.6V, SKIP = BATT)
IN
MAX1820/21 toc15
V
= 1.5V, V = 3.6V, SKIP = GND)
IN
MAX1820/21 toc16
OUT
OUT
I
I
OUT
200mA/div
OUT
200mA/div
V
V
OUT
OUT
AC-COUPLED
100mV/div
AC-COUPLED
100mV/div
C
= 10µF
C
= 10µF
OUT
OUT
40µs/div
40µs/div
MAX1820
LINE TRANSIENT (V = 3.6V TO 4.0V,
IN
REF TRANSIENT (V
= 0.23V TO 1.932V,
REF
V
OUT
= 1.5V, I
= 300mA)
LOAD
MAX1820/21 toc18
R
LOAD
= 10Ω, V = 3.6V, SKIP = BATT)
IN
MAX1820/21 toc17
V
V
IN
REF
1V/div
200mV/div
V
OUT
AC-COUPLED
20mV/div
V
OUT
1V/div
C
= 10µF
OUT
40µs/div
20µs/div
_______________________________________________________________________________________
7
WCDMA Cellular Phone 600mA
Buck Regulators
Typical Operating Characteristics (continued)
(T = +25°C, unless otherwise noted.)
A
OUTPUT SWITCHING HARMONICS
vs. FREQUENCY
OUTPUT SWITCHING HARMONICS
vs. FREQUENCY
(V = 3.8V, V
= 3.4V, I = 600mA)
(V = 3.8V, V
= 1.8V, I
= 300mA)
IN
OUT
LOAD
IN
OUT
LOAD
1.6
1.2
1.6
1.2
0.8
0.4
0.8
0.4
0
0
0.1
1
10
0.1
1
10
FREQUENCY (MHz)
FREQUENCY (MHz)
OUTPUT SWITCHING HARMONICS
vs. FREQUENCY
OUTPUT NOISE (V = 3.6V,
IN
V
= 1.8V, I
= 300mA)
OUT
OUT
(V = 4.2V, V
= 0.4V, I
= 30mA)
IN
OUT
LOAD
4.0
3.0
2.0
1.6
1.2
0.8
1.0
0
0.4
0
0.1
1
10
250
100
0.1
1
10
FREQUENCY (MHz)
FREQUENCY (MHz)
Pin Description
PIN
MAX1821
NAME
FUNCTION
MAX1820
UCSP
MAX1820
µMAX
MAX1821
µMAX
UCSP
PWM/Skip-Mode Input. Drive with logic 0 to use PWM at medium
and heavy loads and pulse skipping at light loads. Drive with
logic 1 to force PWM at all loads.
A1
1
A1
1
SKIP
Compensation. Typically, connect an 82kΩ (for MAX1821) or
43kΩ (for MAX1820) series resistor and 330pF capacitor from
this pin to GND to stabilize the regulator.
A2
A3
2
3
A2
2
COMP
OUT
—
—
Output Voltage Sense Input. Connect OUT directly to the output.
8
_______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
Pin Description (continued)
PIN
NAME
FUNCTION
MAX1820
UCSP
MAX1820
µMAX
MAX1821
UCSP
MAX1821
µMAX
Output Feedback Sense Input. To set the output voltage,
connect FB to the center of an external resistive divider between
the output and GND. FB voltage regulates to 1.25V.
—
—
A3
3
FB
External Reference Input. Connect REF to the output of a D/A
converter for dynamic adjustment of the output voltage. REF-to-
OUT gain is 1.76.
A4
4
—
—
REF
REF
Internal Reference Bypass. Connect a 0.047µF capacitor from
REF to GND.
—
—
A4
4
B4
C4
5
6
B4
C4
5
6
GND
Ground
PGND
Power Ground
Inductor Connection. LX connects to the drains of the internal
power MOSFETs. LX is high impedance in shutdown mode.
C3
7
C3
7
LX
Supply Voltage Input. Connect BATT to a 2.6V to 5.5V source.
Bypass BATT to PGND with a low-ESR 10µF capacitor.
C2
C1
8
9
C2
C1
8
9
BATT
SHDN
Active-Low, Shutdown Control Input
Clock Synchronization Input. Drive SYNC with a 13MHz
(MAX1820X, MAX1821X) or 19.8MHz (MAX1820Y) AC-coupled
sine-wave input to synchronize power switching at 1MHz.
MAX1820Z and MAX1821 do not have SYNC capability.
Connect SYNC to GND to use the internally generated,
free-running 1MHz clock. MAX1820Z and MAX1821 SYNC pin
must be connected to GND.
B1
10
B1
10
SYNC
battery life. An additional forced PWM mode (with
optional external synchronization) switches at a con-
stant frequency, regardless of load, to provide a well-
controlled spectrum in noise-sensitive applications.
Battery life is maximized by low-dropout operation at
100% duty-cycle and a 0.1µA (typ) logic-controlled
shutdown mode.
_______________Detailed Description
The MAX1820/MAX1821 PWM step-down DC-DC con-
verters are optimized for low-voltage, battery-powered
applications where high efficiency and small size are
priorities. The MAX1821 is a general-purpose device
that uses external feedback resistors to set the output
voltage from 1.25V to V
, and the MAX1820 is
BATT
specifically intended to power a linear PA in WCDMA
handsets. An analog control signal dynamically adjusts
the MAX1820’s output voltage from 0.4V to 3.4V with a
settling time <30µs.
PWM Control
The MAX1820/MAX1821 use a slope-compensated,
current-mode PWM controller capable of achieving
100% duty cycle. The current-mode control design is
capable of minimum duty cycles of less than 10%,
ensuring a constant switching frequency with outputs
as low as 0.4V when powered from a single lithium-ion
(Li+) cell. Current-mode feedback provides stable
switching and cycle-by-cycle current limiting for superi-
or load and line response and protection of the internal
MOSFET and synchronous rectifier. The output voltage
is regulated by switching at a constant frequency and
then modulating the power transferred to the load dur-
The MAX1820/MAX1821 operate at a high 1MHz
switching frequency that reduces external component
size. Each device includes an internal synchronous rec-
tifier that provides for high efficiency and eliminates the
need for an external Schottky diode. The normal operat-
ing mode uses constant-frequency PWM switching at
medium and heavy loads, and automatically pulse
skips at light loads to reduce supply current and extend
_______________________________________________________________________________________
9
WCDMA Cellular Phone 600mA
Buck Regulators
BATT
TO
IC BIAS
1.25V
VOLTAGE
REFERENCE
PWM
COMPARATOR
ERROR SIGNAL
SLOPE COMP
GND
CURRENT SENSE
PWM CONTROL
AND
SKIP LOGIC
LX
TRANSIMPEDANCE
ERROR AMP
SKIP
COMPARATOR
OUT
REF
CLAMP
SKIP THRESHOLD
PGND
1MHz
OSCILLATOR
÷13 OR
÷18
MAX1820
Figure 1. MAX1820 Simplified Functional Diagram (No SYNC for MAX1820Z)
BATT
1.25V
TO
IC BIAS
VOLTAGE
REFERENCE
PWM
COMPARATOR
ERROR SIGNAL
SLOPE COMP
GND
CURRENT SENSE
PWM CONTROL
AND
SKIP LOGIC
LX
TRANSIMPEDANCE
ERROR AMP
SKIP
COMPARATOR
OUT
REF
CLAMP
SKIP THRESHOLD
PGND
1MHz
OSCILLATOR
MAX1821
Figure 2. MAX1821 Simplified Functional Diagram (No SYNC for MAX1821)
ing each cycle, using the PWM comparator. The power
transferred to the load is adjusted by changes in the
inductor peak current limit during the first half of each
cycle, based on the output error voltage.
ramp that is summed with the internal P-channel MOS-
FET current (Figures 1 and 2).
The second half of the cycle begins when the reference
ramp is greater than the error voltage. The P-channel
MOSFET is turned off, the synchronous rectifier is
turned on, and inductor current continues to flow to the
output capacitor. The output capacitor stores charge
when the current is high and releases it when the
inductor current is low, smoothing the voltage across
A new cycle begins at each falling edge of the internal
oscillator. The controller turns on the P-channel MOS-
FET to increase the inductor current, and the slope
compensation block initiates a new reference current
10 ______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
4.7µH
V
= 2.6V TO 5.5V
V
OUT
= 1.5V
IN
BATT
LX
10µF
0.1µF
4.7µF
R1
6kΩ
MAX1821
SHDN
SYNC
PGND
FB
REF
R2
30kΩ
0.047µF
COMP
R
C
C2*
1pF
SKIP
GND
82kΩ
C1
330pF
* CAN BE OMITTED IF CERAMIC OUTPUT CAPACITOR IS USED.
Figure 3. Standard Operating Circuit
the load. The duty cycle of a buck step-down converter
is ideally a ratio of the output voltage to input voltage in
steady-state condition.
There are three steady-state operating conditions for
the MAX1820/MAX1821 in normal mode. The device
performs in continuous conduction for heavy loads in a
manner identical to forced PWM mode. The inductor
current becomes discontinuous at medium loads,
requiring the synchronous rectifier to be turned off
before the end of a cycle as the inductor current reach-
es zero. The device enters into skip mode when the
converter output voltage exceeds its regulation limit
before the inductor current reaches its skip thres-
hold level.
The MAX1820/MAX1821 have internal switch current
limits of 1.2A (typ). If I exceeds this maximum, the
LX
high-side FET turns off and the synchronous rectifier
turns on. This lowers the duty cycle and causes the out-
put voltage to droop as long as the load current
remains excessive. There is also a synchronous rectifier
current limit of -0.85A when the device is operating in
forced PWM mode (see the Forced PWM Operation sec-
tion). If the negative current limit is exceeded, the syn-
chronus rectifier is turned off, and the inductor current
continues to flow through its body diode until the begin-
ning of the next cycle or the inductor current drops to
zero. This means there is a limit on how much current
the device is allowed to shuttle in response to output
power reduction.
During skip mode, a switching cycle initiates when the
output voltage has dropped out of regulation. The P-
channel MOSFET switch turns on and conducts current
to the output-filter capacitor and load until the inductor
current reaches the skip peak current limit. Then the
main switch turns off, and the magnetic field in the
inductor collapses, while current flows through the syn-
chronous rectifier to the output filter capacitor and the
load. The synchronous rectifier is turned off when the
inductor current reaches zero. The MAX1820/ MAX1821
wait until the skip comparator senses a low output volt-
age again.
Normal Mode Operation
Connecting SKIP to GND enables MAX1820/MAX1821
normal operation (Figure 3). This allows automatic PWM
control at medium and heavy loads and skip mode at
light loads to improve efficiency and reduce quiescent
current to 180µA. Operating in normal mode also allows
the MAX1820/MAX1821 to pulse skip when the peak
inductor current drops below 130mA, corresponding to
a load current of approximately 65mA.
Forced PWM Operation
Connect SKIP to BATT for forced PWM operation.
Forced PWM operation is desirable in sensitive RF and
data-acquisition applications to ensure that switching
harmonics do not interfere with sensitive IF and data-
sampling frequencies. A minimum load is not required
during forced PWM operation since the synchronous
rectifier passes reverse-inductor current as needed to
allow constant-frequency operation with no load.
During skip operation, the MAX1820/MAX1821 switch
only as needed to service the load, reducing the
switching frequency and associated losses in the inter-
nal switch, the synchronous rectifier, and the external
inductor.
______________________________________________________________________________________ 11
WCDMA Cellular Phone 600mA
Buck Regulators
Forced PWM operation uses higher supply current with
no load (3.3mA typ) compared to skip mode.
current falls. In normal mode, the synchronous rectifier
is turned off when either the output falls out of regula-
tion (and another on-time begins) or when the inductor
current approaches zero. In forced PWM mode, the
synchronous rectifier remains active until the beginning
of a new cycle.
100% Duty-Cycle Operation
The on-time can exceed one internal oscillator cycle,
which permits operation up to 100% duty cycle. As the
input voltage drops, the duty cycle increases until the
P-channel MOSFET is held on continuously. Dropout
voltage in 100% duty cycle is the output current multi-
plied by the on-resistance of the internal switch and
SYNC Input and Frequency Control
The MAX1820Z and MAX1821 internal oscillator is set
to a fixed 1MHz switching frequency. The MAX1820Z
and MAX1821 do not have synchronizing capability
and the SYNC pin must be connected to GND. The
MAX1820Y, MAX1820X, and MAX1821X are capable of
synchronizing to external signals. For external synchro-
nization, drive the SYNC pin with a 13MHz (MAX1820X
and MAX1821X) or 19.8MHz (MAX1820Y) AC-coupled
sine wave. SYNC has a perfect 13:1 (MAX1820X and
MAX1821X) or 18:1 (MAX1820Y) clock divider for 1MHz
(MAX1820X and MAX1821X) or 1.1MHz (MAX1820Y)
switching from common system clocks. The input fre-
quency range for SYNC is 10MHz to 16MHz
(MAX1820X, MAX1821X) or 15MHz to 21MHz
(MAX1820Y). Connect SYNC to GND to use the internal
free-running oscillator at 1MHz.
inductor, approximately 150mV (I
= 600mA). Near
OUT
dropout, the on-time may exceed one PWM clock
cycle; therefore, small-amplitude subharmonic ripple
may occur.
COMP Clamp
The MAX1820/MAX1821 compensation network has a
0.45V to 2.15V error regulation range. The clamp pre-
vents COMP from rising too high or falling too low to
optimize transient response.
Dropout
Dropout occurs when the input voltage is less than the
desired output voltage plus the IR drops in the circuit
components. The duty cycle is 100% during this condi-
tion, and the main switch remains on, continuously
delivering current to the output up to the current limit.
IR drops in the circuit are primarily caused by the on-
resistance of the main switch and the resistance in the
inductor.
Shutdown Mode
Drive SHDN to GND to place the MAX1820/MAX1821 in
shutdown mode. In shutdown, the reference, control
circuitry, internal switching MOSFET, and the synchro-
nous rectifier turn off, reducing the supply current to
0.1µA, and the output goes high impedance. Connect
SHDN to BATT for normal operation.
During dropout, the high-side P-channel MOSFET turns
on, and the controller enters a low-current consumption
mode. Every 6µs (6 cycles), the MAX1820/MAX1821
check to see if the device is still in dropout. The device
remains in this mode until the MAX1820/MAX1821 are
no longer in dropout.
Current-Sense Comparators
The MAX1820/MAX1821 use several internal current-
sense comparators. In PWM operation, the PWM com-
parator terminates the cycle-by-cycle on-time (Figures
1 and 2) and provides improved load and line
response. This allows tighter specification of the induc-
tor-saturation current limit to reduce inductor cost. A
second current-sense comparator used across the P-
channel switch controls entry into skip mode. A third
current-sense comparator monitors current through the
internal N-channel MOSFET to prevent excessive
reverse currents and determine when to turn off the
synchronous rectifier. A fourth comparator used at the
P-channel MOSFET detects overcurrent. This protects
the system, external components, and internal
MOSFETs under overload conditions.
Undervoltage Lockout (UVLO)
The MAX1820/MAX1821 do not operate with battery
voltages below the UVLO threshold of 2.35V (typ). The
BATT input remains high impedance until the supply
voltage exceeds the UVLO threshold. This guarantees
the integrity of the output voltage regulation and pre-
vents excessive current during startup and as the bat-
tery supply voltage drops during usage.
Synchronous Rectification
An N-channel synchronous rectifier eliminates the need
for an external Schottky diode and improves efficiency.
The synchronous rectifier turns on during the second
half of each cycle (off-time). During this time, the volt-
age across the inductor is reversed, and the inductor
12 ______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
Compensation and Stability
Applications Information
The MAX1820/MAX1821 are externally compensated
Setting the Output Voltage (MAX1820)
The MAX1820 is optimized for highest system efficiency
when applying power to a linear PA in WCDMA hand-
sets. When transmitting at less than full power, the sup-
ply voltage to the PA is reduced (from 3.4V to as low as
0.4V) to greatly reduce battery current. Figure 4 shows
the typical WCDMA PA load profile. The use of a DC-
DC converter such as the MAX1820 dramatically
reduces battery drain in these applications.
by placing a resistor and a capacitor (R and C1) in
C
series, from COMP to GND (Figure 3). The capacitor
integrates the current from the transimpedance amplifi-
er, averaging output capacitor ripple. This sets the
device speed for transient responses and allows the
use of small ceramic output capacitors because the
phase-shifted capacitor ripple does not disturb the cur-
rent regulation loop. The resistor sets the proportional
✕
gain of the output error voltage by a factor g
R .
C
m
Increasing this resistor also increases the sensitivity of
the control loop to the output capacitor ripple.
3.4
3.0
This resistor and capacitor set a compensation zero
that defines the system’s transient response. The load
pole is a dynamic pole, shifting the pole frequency with
changes in load. As the load decreases, the pole fre-
quency shifts to the left. System stability requires that
the compensation zero must be placed properly to
ensure adequate phase margin (at least 30° at unity
gain). The following is a design procedure for the com-
pensation network:
1.0
0.4
1) Select an appropriate converter bandwidth (f ) to
C
stabilize the system while maximizing transient
response. This bandwidth should not exceed 1/5 of
the switching frequency. Use 100kHz as a reason-
able starting point.
30
300
600
WCDMA PA SUPPLY CURRENT (mA)
Figure 4. Typical WCDMA PA Load Profile
2) Calculate the compensation capacitor, C1, based
on this bandwidth:
The MAX1820’s output voltage is dynamically
V
1
R2
1
O(MAX)
adjustable from 0.4V to V
input. The gain from V
by the use of the REF
BATT
to V
C1 =
g ×
m
is internally set to
OUT
REF
I
R
R1+R2 2× π × f
O(MAX) CS
C
1.76. V
can be adjusted during operation by driving
OUT
REF with an external DAC. The MAX1820 output
responds to full-scale change in voltage and current in
<30µs.
Resistors R1 and R2 are internal to the MAX1820; use
R1 = 151kΩ and R2 = 199kΩ as nominal values for cal-
culations. These resistors are external to the MAX1821
(see the Setting the Output Voltage section). Using
Setting the Output Voltage (MAX1821)
The MAX1821 is intended for general-purpose step-
down applications where high efficiency is a priority.
V
= 3.4V, I
= 0.6A, g = 50µs, R = 0.75Ω,
OMAX
OMAX
m
CS
C1 is evaluated as:
Select an output voltage between 1.25V and V
by
BATT
3.4V
0.6A 0.75Ω
1
199kΩ
151kΩ+199kΩ
TC1 =
50µs ×
connecting FB to a resistive divider between the output
and GND (Figure 3). Select feedback resistor R2 in the
5kΩ to 30kΩ range. R1 is then given by:
1
×
= 341pF
2× 3.14×100kHz
V
V
OUT
R1 = R2
-1
Selecting the nearest standard value of 330pF corre-
sponds to a 103kHz bandwidth, which is still accept-
able per the above criteria.
FB
where V = 1.25V.
FB
______________________________________________________________________________________ 13
WCDMA Cellular Phone 600mA
Buck Regulators
Table 1. Suggested Inductors
INDUCTANCE
SATURATION
CURRENT (A)
DIMENSIONS
(mm)
MANUFACTURER
PART NUMBER
ESR (mΩ)
(µH)
✕
✕
Coilcraft
DO1606
4.7
4.7
4.7
4.7
4.1
120
240 (max)
125
1.2
1.2
5.3 5.3 2.0
✕
✕
Coilcraft
Sumida
Sumida
Sumida
LPT1606-472
CDRH4D18-4R7
CR43
6.5 5.3 2.0
✕
✕
0.84
1.15
1.95
5
5
2
✕
✕
108.7
57
4.5 4.0 3.5
✕
✕
CDRH5D18-4R1
5.5 5.5 2.0
3) Calculate the equivalent load impedance, R , by:
For most designs, a reasonable inductor value (L
)
IDEAL
L
can be derived from the following equation:
V
OUT(MAX)
R ≈
L
V
(V
-V
)
OUT BATT OUT
I
L
=
OUT(MAX)
IDEAL
V
×LIR×I
× ƒ
BATT
OUT(MAX) OSC
4) Calculate the compensation resistance (R ) value to
C
cancel out the dominant pole created by the output
load and the output capacitance:
where LIR is the inductor current ripple as a percentage.
LIR should be kept between 20% and 40% of the maxi-
mum load current for best performance and stability.
1
1
The maximum inductor current is:
=
2× π ×R ×C
2× π ×R ×C1
C
L
OUT
LIR
2
I
= 1+
I
OUT(MAX)
L(MAX)
Solving for R gives:
C
R ×C
3.4V
0.6A 330pF
4.7µF
L
OUT
The inductor current becomes discontinuous if I
OUT
R
=
=
= 80.8kΩ
C
C1
decreases to LIR/2 from the output current value used
to determine L
.
IDEAL
5) Calculate the high-frequency compensation pole to
cancel the zero created by the output capacitor’s
equivalent series resistance (ESR):
Input Capacitor Selection
The input capacitor reduces the current peaks drawn
from the battery or input power source and reduces
switching noise in the IC. The impedance of the input
capacitor at the switching frequency should be less
than that of the input source so high-frequency switch-
ing currents do not pass through the input source.
1
1
=
`
2× π ×R
×C
2× π ×R3×C2
ESR
OUT
Solving for C2 gives:
The input capacitor must meet the ripple-current
R
×C
R3
4.7µF × 0.01Ω
80.8kΩ
requirement (I
) imposed by the switching currents.
ESR
OUT
RMS
C2 =
=
= 0.55pF
Nontantalum chemistries (ceramic, POSCAP, or OS-
CON) are preferred due to their resistance to power-up
surge currents:
In this case, C2 can be omitted due to the use of
ceramic capacitors. Larger output capacitors and high-
er ESR may require the use of capacitor C2.
VOUT(VBATT -VOUT
)
IRMS = I
LOAD
VBATT
Inductor Selection
A 4µH to 6µH inductor with a saturation current of at
least 800mA is recommended for most applications.
For best efficiency, the inductor’s DC resistance should
be <200mΩ, and saturation current should be >1A. See
Table 1 for recommended inductors and manufacturers.
For optimal circuit reliability, choose a capacitor that
has less than 10°C temperature rise at the peak ripple
current.
14 ______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
Output Capacitor Selection
Table 2. Capacitor Selection
The output capacitor is required to keep the output volt-
age ripple small and to ensure regulation control loop
stability. The output capacitor must have low imped-
ance at the switching frequency. Ceramic capacitors
are recommended. The output ripple is approximately:
CAPACITOR
VALUE (µF)
ESR
(mΩ)
CAPACITOR
TYPE
CAPACITOR
C
C
4.7 to 10
<150
Ceramic
BATT
OUT
2.2 to 4.7
<50
Ceramic
(MAX1820)
✕
V
≈ LIR
I
OUT(MAX)
RIPPLE
C
OUT
4.7 to 10
<150
Ceramic
(MAX1821)
1
× ESR +
2 × ƒ
(
× C
OUT
)
OSC
Table 3. Component Manufacturers
See the Compensation Design section for a discussion
of the influence of output capacitance and ESR on reg-
ulation control-loop stability.
USA PHONE
NUMBER
MANUFACTURER
WEBSITE
The capacitor voltage rating must exceed the maximum
applied capacitor voltage. Consult the manufacturer’s
specifications for proper capacitor derating. Avoid Y5V
and Z5U dielectric types due to their huge voltage and
temperature coefficients of capacitance and ESR.
Coilcraft
Kemet
847-639-6400
408-986-0424
847-468-5624
847-956-0666
408-573-4150
www.coilcraft.com
www.kemet.com
Panasonic
Sumida
www.panasonic.com
www.sumida.com
www.t-yuden.com
Taiyo Yuden
PC Board Layout and Routing
High switching frequencies and large peak currents
make PC board layout a very important part of design.
Good design minimizes excessive EMI on the feedback
paths and voltage gradients in the ground plane, both
of which can result in instability or regulation errors.
Connect the inductor, input filter capacitor, and output
filter capacitor as close together as possible, and keep
their traces short, direct, and wide. Connect their
ground pins at a single common node in a star-ground
configuration. The external voltage-feedback network
should be very close to the FB pin, within 0.2in (5mm).
Keep noisy traces (from the LX pin, for example) away
from the voltage-feedback network; also, keep them
separate, using grounded copper. Connect GND and
PGND at a single point, as close as possible to the
MAX1820/MAX1821. The MAX1820/MAX1821 evalua-
tion kit manual illustrates an example PC board layout
and routing scheme.
______________________UCSP Reliability
The chip-scale package (UCSP) represents a unique
packaging form factor that may not perform equally to a
packaged product through traditional mechanical relia-
bility tests. UCSP reliability is integrally linked to the
user’s assembly methods, circuit board material, and
usage environment. The user should closely review
these areas when considering use of a UCSP package.
Performance through Operating Life Test and Moisture
Resistance remains uncompromised as it is primarily
determined by the wafer-fabrication process.
Mechanical stress performance is a greater considera-
tion for a UCSP package. UCSPs are attached through
direct solder contact to the user’s PC board, foregoing
the inherent stress relief of a packaged-product lead
frame. Solder joint contact integrity must be consid-
ered. Information on Maxim’s qualification plan, test
data, and recommendations are detailed in the UCSP
application note, which can be found on Maxim’s website,
www.maxim-ic.com.
UCSP Package Consideration
For general UCSP package information and PC layout
considerations, refer to the Maxim Application Note
(Wafer-Level Ultra-Chip-Board-Scale Package).
____________________Chip Information
TRANSISTOR COUNT: 2722
______________________________________________________________________________________ 15
WCDMA Cellular Phone 600mA
Buck Regulators
Ordering Information (continued)
SYNC
FREQ (MHz)
PART
OUTPUT VOLTAGE
TEMP RANGE
PIN-PACKAGE
UCSP MARK
No Sync
No Sync
13
✕
MAX1821EBC*
MAX1821EUB
MAX1821XEBC*
MAX1821XEUB
Programmable
Programmable
Programmable
Programmable
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
3
4 UCSP
AAC
—
10 µMAX
✕
3
4 UCSP
AAV
—
13
10 µMAX
*UCSP reliability is integrally linked to the user’s assembly methods, circuit board material, and environment. Refer to the UCSP
Reliability Notice in the UCSP Reliability section for more information.
Typical Operating Circuits (continued)
INPUT
2.6V TO
5.5V
OUTPUT
1.25V TO 5.5V
BATT
LX
PGND
FB
SHDN
MAX1821
COMP
SYNC
REF
SKIP
GND
Pin Configurations
TOP VIEW AFTER ASSEMBLED ON PC BOARD (BUMPS AT THE BOTTOM)
TOP VIEW
4
2
3
1
SKIP
COMP
OUT (FB)
REF
1
2
10 SYNC
SKIP
A1
COMP
A2
OUT (FB)
A3
REF
A4
A
B
C
9
8
7
6
SHDN
BATT
LX
MAX1820
3
4
5
MAX1821
SYNC
B1
GND
B4
GND
PGND
SHDN
C1
BATT
C2
LX
C3
PGND
C4
µMAX
( ) ARE FOR MAX1821 ONLY.
UCSP
( ) ARE FOR MAX1821 ONLY.
16 ______________________________________________________________________________________
WCDMA Cellular Phone 600mA
Buck Regulators
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
______________________________________________________________________________________ 17
WCDMA Cellular Phone 600mA
Buck Regulators
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages.)
e
4X S
10
10
INCHES
MAX
MILLIMETERS
MAX
1.10
0.15
0.95
3.05
3.00
3.05
3.00
5.05
0.70
DIM MIN
MIN
-
A
-
0.043
0.006
0.037
0.120
0.118
0.120
0.118
0.199
A1
A2
D1
D2
E1
E2
H
0.002
0.030
0.116
0.114
0.116
0.114
0.187
0.05
0.75
2.95
2.89
2.95
2.89
4.75
0.40
H
ÿ 0.50±0.1
0.6±0.1
L
0.0157 0.0275
0.037 REF
L1
b
0.940 REF
0.007
0.0106
0.177
0.270
0.200
1
1
e
0.0197 BSC
0.500 BSC
0.6±0.1
c
0.0035 0.0078
0.0196 REF
0.090
BOTTOM VIEW
0.498 REF
S
α
TOP VIEW
0∞
6∞
0∞
6∞
D2
E2
GAGE PLANE
A2
c
A
E1
b
L
α
A1
D1
L1
FRONT VIEW
SIDE VIEW
PROPRIETARY INFORMATION
TITLE:
PACKAGE OUTLINE, 10L uMAX/uSOP
APPROVAL
DOCUMENT CONTROL NO.
REV.
1
21-0061
I
1
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
18 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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