ACT8712
PIN DESCRIPTIONS CONT’D
PIN
17
18
19
20
21
Rev0, 25-Feb-08
NAME
GA
FB3
OVP3
GP3
SW3
DESCRIPTION
Analog Ground. Connect GA directly to a quiet ground node. Connect GA, GP12, and GP3
together at a single point as close to the IC as possible.
Feedback Sense for REG3. Connect this pin to the LED string current sense resistor to
sense the LED current.
Over-Voltage Protection Input for REG3. Connect this pin directly to the output node to
sense and prevent over-voltage conditions.
Power Ground for REG3. Connect GP3 directly to a power ground plane. Connect GA,
GP12, and GP3 together at a single point as close to the IC as possible.
Switching Node Output for REG3. Connect this pin to the switching end of the inductor.
Active-Low Open-Drain Charger Status Output. nSTAT sinks current whenever the charger
is charging the battery, and is high-Z otherwise. nSTAT has a 6mA (typ) current limit, allow-
ing it to directly drive an indicator LED without additional external components. To generate
a logic-level output, connect nSTAT to an appropriate supply voltage (typically OUT2)
through a 10kΩ or greater pull-up resistor.
Tri-State Charging State Select Input. When ISET1[ ] = [0000], drive CHGLEV to VSYS or
to a logic high for high-current charging mode (maximum charge current of 500mA), and
drive to GA or a logic low for low-current charging mode (maximum charge current of
100mA). Allow CHGLEV to float (|I
CHGLEV
| < 2µA) to disable the charger.
Battery Charger Output. Connect this pin directly to the battery anode (+ terminal) to sense
the battery voltage.
Exposed Pad. Must be soldered to ground on PCB.
22
nSTAT
23
CHGLEV
24
EP
BAT
EP
Innovative Products.
Active Solutions.
ActivePMU
is a trademark of Active-Semi.
I
2
C
TM
is a trademark of Philips Electronics.
TM
-6-
www.active-semi.com
Copyright © 2008 Active-Semi, Inc.
ACTIVE-SEMI [ ACTIVE-SEMI, INC ]
