Datasheet

MAX8808X/MAX8808Y/MAX8808Z
1A Linear Li+ Battery Chargers with Integrated Pass
FET and Thermal Regulation in 2mm x 2mm TDFN
_______________________________________________________________________________________ 5
Pin Description
PIN NAME FUNCTION
1IN
Input Supply Voltage. Bypass IN to GND with a 1µF or larger ceramic capacitor to improve line
noise and input transient rejection.
2VLInternally Generated Logic Supply for IC. Bypass VL to GND with a 0.47µF ceramic capacitor.
3 GND
Ground. Connect GND and exposed pad to a large copper ground plane for maximum power
dissipation. Connect GND to the exposed paddle directly under the IC.
4 ISET
Charge-Current Program and Fast-Charge Current Monitor. Output current from ISET is 1.08mA
per amp of battery charging current. Set the charging current by connecting a resistor from ISET
to GND. Fast-charge current = 1302V / R
ISET
Ω.
5 CHG
Charging Indicator. CHG is an open-drain output that goes low (LED capable) when charging
begins. CHG is high impedance when the battery current drops below 10% of the fast-charging
current, or when the IC is disabled. Connect a pullup resistor to the µP’s I/O voltage when
interfacing with a µP logic input.
EN
(MAX8808X/
MAX8808Z)
Logic-Level Enable Input. Drive EN high to disable charger. Pull EN low or leave unconnected for
normal operation. EN has an internal 200kΩ pulldown resistor.
6
EN
(MAX8808Y)
Logic-Level Enable Input. Drive EN low to disable charger. Pull EN high for normal operation. EN
has no internal pullup or pulldown resistor.
7 ACOK
Input Status Indicator. ACOK is an open-drain output that asserts low when V
IN
< +7V and (V
IN
–
V
BATT
) ≥ 40mV. ACOK requires an external 100kΩ pullup resistor. ACOK is high impedance
during shutdown.
8 BATT
Li+ Battery Connection. Bypass BATT to GND with a ceramic capacitor of at least 2.2µF per
ampere of charge current.
—EP
Exposed Paddle. Connect the exposed paddle to a large ground plane for maximum power
dissipation. Connect GND to the exposed paddle directly under the IC.