Datasheet

SYS
BAT
4.7uF
TS
NTC
AC
ISET
2.2uF
1uF
LiIon
SYS
PB_IN
VLDO1
THRESHOLD
RESET
SCLK
SDAT
set
charge
current
LDO1
200mA
BAT
INT
charger / powerpath
ON /
OFF
FB_DCDC1
2.2uH
L1
DCDC1
200mA
4.7uF
TPS65721
SYS
VINLDO1
Vout1
Vout2
GPIO1
GPIO2
GPIO0
GPIO3
GPIOor
5mA current
sink
I2Cinterface
reset
generator /
startuplogic
PGND
AGND
HOLD_LDO1
HOLD_DCDC1
MODE
FB_LDO1
AC
R5
R6
R1
R2
R3
R4
22pF
TPS65720
TPS65721
www.ti.com SLVS979 –OCTOBER 2009
FUNCTIONAL BLOCK DIAGRAM
PIN FUNCTIONS for QFN VERSION (RSN package)
PIN
I/O DESCRIPTION
NAME NO.
AC 17, 18 I Input power for power manager, connect to external DC supply.
SYS 19, 20 O System voltage; output of the power path manager. Power input for step-down converter DCDC1
BAT 21, 22 I/O Connect to battery + terminal
ISET 16 I Connect a resistor from this pin to GND to set fast charge current
TS 27 I Connect a thermistor from this pin to GND for battery temperature
AGND 28 Analog ground
PGND 24 Power ground
L1 23 O Switch output of step-down converter
FB_DCDC1 26 I Feedback input of step-down converter
HOLD_DCDC1 25 I Power-On input for DCDC1 converter. When pulled HIGH, the DCDC converter is kept enabled after
PB_IN was released HIGH.
VINLDO1 30 I Input voltage for LDO1
VLDO1 31 O Output voltage from LDO1
FB_LDO1 1 I Feedback input for LDO1
HOLD_LDO1 2 I Power-On input for LDO1. When pulled HIGH, LDO1 is kept enabled after PB_IN was released
HIGH.
SDAT 12 I/O Data line for the I2C interface
SCLK 8 I Clock input for the I2C interface
PB_IN 15 I Push button input; Turns on DCDC1 and LDO1 if pulled to GND.
INT 13 O Open drain interrupt output
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