LTC3521 Datasheet, PDF (20/20 Pages) Linear Technology – Wide VIN, 1A Buck-Boost DC/DC and Dual 600mA Buck DC/DC Converters

LTC3521
TYPICAL APPLICATION
V_IN
2.4V TO
4.2V
+
V_OUT3
1.2V
600mA
Li-Ion to 3.3V at 800mA, 1.8V at 600mA and 1.2V at
600mA with Sequenced Start-Up
Li-Ion
4.7µF ^L1
4.7µH
L3
4.7µH
C3
R5
10µF 100k
R6
499k
100k
PV_IN1
SW1A
SW1B
PV_IN2
SW2
FB2
SW3
LTC3521
FB3
V_OUT1
PGOOD1
PWM
BURST
FB1
PGOOD3
SHDN1
SHDN2
PGOOD1 PGOOD2
PWM
SHDN3
PGND1 GND PGND2
L2
4.7µH
R3
137k
R4
68.1k
R1
1.0M
R2
221k
R5
499k
ON
OFF
V_OUT2
1.8V
C2 _600mA
10µF
V_OUT1
3.3V
800mA
C1
22µF
(1A,
V_IN
>
3.0V)
3521 TA03a
Sequenced Start-Up Waveforms
V_OUT2
2V/DIV
V_OUT3
2V/DIV
V_OUT1
2V/DIV
SHDN2, 5V/DIV
PGOOD2, 5V/DIV
PGOOD3, 5V/DIV
500µs/DIV
3521 TA03b
Related Parts
PART NUMBER
DESCRIPTION
COMMENTS
LTC3100
LTC3101
700mA I_SW, 1.5MHz, Synchronous Step-Up, 250mA
94% Efficiency, V_IN: 0.7V to 5V, V_OUT(MAX) = 5.25V, I_Q = 15µA,
Synchronous Step-Down DC/DC Converter and 100mA LDO I_SD < 1µA, 3mm × 3mm QFN-16 Package
Wide V_IN, Multioutput DC/DC Converter and PowerPath™
Controller, 800mA Buck-Boost, Dual 350mA Buck
Converters, 50mA Always-On LDO
95% Efficiency, V_IN: 1.8V to 5.5V, I_Q = 38µA, Standby I_Q = 15µA,
4mm × 4mm QFN-24 Package
LTC3409
600mA I_OUT, 1.7MHz/2.6MHz, Synchronous Step-Down
DC/DC Converter
LTC3441/LTC3442/ 1.2A I_OUT, 2MHz, Synchronous Buck-Boost DC/DC
LTC3443
Converter
LTC3520
1A 2MHz, Synchronous Buck-Boost and 600mA Buck
Converter
LTC3522
400mA 2MHz, Synchronous Buck-Boost and 200mA Buck
Converter
LTC3531/LTC3531-3/ 200mA I_OUT, 1.5MHz, Synchronous Buck-Boost DC/DC
LTC3531-3.3
Converter
LTC3532
500mA I_OUT, 2MHz, Synchronous Buck-Boost DC/DC
Converter
LTC3547
Dual 300mA I_OUT, 2.25MHz, Synchronous Step-Down
DC/DC Converter
96% Efficiency, V_IN: 1.6V to 5.5V, V_OUT(MIN) = 0.6V, I_Q = 65µA,
I_SD < 1µA, DFN Package
95% Efficiency, V_IN: 2.4V to 5.5V, V_OUT(MIN): 2.4V to 5.25V,
I_Q = 50µA, I_SD < 1µA, DFN Package
95% Efficiency, V_IN: 2.2V to 5.5V, V_OUT(MAX) = 5.25V, I_Q = 55µA,
I_SD < 1µA, 4mm × 4mm QFN-24 Package
95% Efficiency, V_IN: 2.4V to 5.5V, V_OUT(MAX) = 5.25V, I_Q = 25µA,
I_SD < 1µA, 3mm × 3mm QFN-16 Package
95% Efficiency, V_IN: 1.8V to 5.5V, V_OUT(MIN): 2V to 5V, I_Q = 16µA,
I_SD < 1µA, ThinSOT and DFN Packages
95% Efficiency, V_IN: 2.4V to 5.5V, V_OUT(MIN): 2.4V to 5.25V,
I_Q = 35µA, I_SD < 1µA, MS10 and DFN Packages
95% Efficiency, V_IN: 2.5V to 5.5V, V_OUT(MIN) = 0.6V, I_Q = 40µA,
I_SD < 1µA, DFN-8 Package
20 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3521f
LT 0310 • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2010