Datasheet

www.ti.com
PIN ASSIGNMENTS
bq24702
bq24703
SLUS553E – MAY 2003 – REVISED OCTOBER 2007
Table 1. TERMINAL FUNCTIONS
TERMINAL
I/O DESCRIPTION
bq24702 bq24703
NAME
(PW) (QFN)
ACDET 1 26 I AC or adapter power detection
ACDRV 24 25 O AC or adapter power source selection output
ACN 11 8 I Negative differential input
ACP 12 9 I Positive differential input
ACPRES 2 27 O AC power indicator
ACSEL 3 28 I AC adapter power select
ACSET 6 3 I Adapter current programming voltage
ALARM 19 19 O Alarm output
BATDEP 4 1 I Depleted battery level
BATDRV 23 24 O Battery power source select output
BATP 13 12 I Battery charge regulation voltage measurement input to the battery-voltage g
m
amplifier
BATSET 9 6 I External override to an internal precision reference
COMP 10 7 O Inverting input to the PWM comparator
ENABLE 8 5 I Charge enable
GND 17 17 O Supply return and ground reference
IBAT 14 13 O Battery current differential amplifier output
PWM 21 21 O Gate drive output
SRN 15 15 I Negative differential battery current sense amplifier input
SRP 16 16 I/O Positive differential battery current sense amplifier input
SRSET 5 2 I Battery charge current programming voltage
VCC 22 22 I Operational supply voltage
VHSP 20 20 O Voltage source to drive gates of the external MOSFETs
VREF 7 4 O Precision 5-V reference
VS 18 18 I System (load) voltage input pin
ACDET: AC or adapter power detection. This input pin is used to determine the presence of the ac adapter.
When the voltage level on the ACDET pin is less than V
ACPRES
, the bq24702/bq24703 is in sleep mode, the
PWM control is disabled, the BATDRV is driven low, and the ACDRV is driven high. This feature can be used to
automatically select battery as the system power source.
ACDRV: AC or adapter power source select output. This pin drives an external P-channel MOSFET used to
switch to the ac wall-adapter as the system power source. When the ACSEL pin is high while the voltage on the
ACDET pin is greater than V
ACPRES
, the output ACDRV pin is driven low (V
HSP
). This pin is driven high (V
CC
)
when the ACDET is less than V
ACPRES
.
ACN, ACP: Negative and positive differential inputs, respectively for ac-to-dc adapter current sense resistor.
ACPRES: This open-drain output pin is used to indicate the presence of ac power. A logic high indicates there is
a valid ac input. A low indicates the loss of ac power. ACPRES is high when the voltage level on the ACDET pin
is greater than V
ACPRES
.
ACSEL: AC adapter power select. This input selects either the ac adapter or the battery as the power source. A
logic high selects ac power, while a logic low selects the battery.
ACSET: Adapter current programming voltage. This input sets the system current level at which dynamic power
management occurs. Adapter currents above this programmed level activate the dynamic power management
and proportionally reduce the available power to the battery.
12 Submit Documentation Feedback Copyright © 2003 – 2007, Texas Instruments Incorporated
Product Folder Link(s): bq24702 bq24703