MAX8939 Datasheet, PDF (14/43 Pages) Maxim Integrated Products – System Power Management for Mobile Handset Hardware Input Enable

System Power Management
for Mobile Handset
Pin Description (continued)
PIN
NAME
FUNCTION
C1
LED3
Indicator LED Connection. Connect LED3 to the cathode of the precharge indicator LED. If a
precharge indicator LED is not used, leave LED3 unconnected.
C2
LED2 25mA LED Current Regulator. Connect LED2 to the cathode of the second LED string.
C3
CHG
Charger Disable Input. Connect CHG high to disable the charger, or low to enable the charger. Once
the charger is enabled or disabled through I²C, the state of CHG is ignored until reset.
C4
SDA
Data Input for Serial Interface. High impedance when the I²C interface is off.
C5
LDO3
200mA LDO Output. Connect a 2.2FF capacitor from LDO3 to ground. In shutdown, LDO3 is pulled
to ground through an internal 100I.
C6
LDO2
200mA LDO Output. Connect a 2.2FF capacitor from LDO2 to ground. In shutdown, LDO2 is pulled
to ground through an internal 100I.
4.9V Regulated LDO Output with Input Overvoltage Protection. Connect a 1FF ceramic capacitor
D1
SAFE_OUT from SAFE_OUT to ground. SAFE_OUT can be used to supply low-voltage-rated USB systems and
the precharge indicator.
D2
OUTVIB
Vibrator Driver Output. Connect OUTVIB to the vibrator motor. Connect a 1FF ceramic capacitor from
OUTVIB to ground.
D3
IRQ
Interrupt Request Open-Drain Output
D4
PWR_ON Open-Drain Output to Wake Sleeping Baseband. PWR_ON_CMP pulses low while the charger is
_CMP connected. See the PWR_ON_CMP section for details.
D5
LDO4
100mA LDO Output. Connect a 1FF capacitor from LDO4 to ground. In shutdown, LDO4 is pulled to
ground through an internal 100I.
D6
LDO1
400mA LDO Output. Connect a 4.7FF capacitor from LDO1 to ground. In shutdown, LDO1 is pulled
to ground through an internal 50I.
Charger Input Supply Voltage. CHG_IN is the power-supply input for the SAFE_OUT linear regulator
E1
CHG_IN
and the battery charger. The operating range for the charger input is 4.1V to 10V. CHG_IN is
protected up to 28V. When VCHG_IN exceeds 10.6V, SAFE_OUT and the charger are disabled.
Connect a 1FF or larger ceramic capacitor from CHG_IN to ground.
Charge Current Monitoring Analog Output. CHG_MON outputs a voltage proportional to the charge
E2
CHG_MON
current with 1.2V corresponding to the programmed fast-charge current. The CHG_MON output
includes ripple from loads on the battery. If this is not desired, connect a small 0.01FF to 0.1FF
capacitor at the input of the ADC to filter the ripple.
E3
INVIB
Input Supply for the Vibrator Driver. Connect INVIB to BATT. Connect a 1FF ceramic capacitor from
INVIB to PGND.
E4
BATT Battery Connection and IC Supply Voltage. Connect a 10FF ceramic capacitor from BATT to ground.
E5
AGND Analog Ground. Connect PGND1, PGND2, and AGND to the PCB ground plane.
E6
REF
Reference Noise Bypass. Connect a 0.1FF ceramic capacitor from REF to AGND. Do not load. REF is
high impedance when shut down.
14   �������������������������������������������������������������������������������������