Datasheet

MAX8814
28V Linear Li+ Battery Charger with
Smart Autoboot Assistant
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Pin Description
PIN NAME FUNCTION
1IN
Input Supply Voltage. Bypass IN to GND with a 1µF or larger ceramic capacitor to minimize line noise
and maximize input transient rejection.
2 GND
Ground. Connect GND and the exposed paddle to a large copper ground plane for maximum power
dissipation. Connect GND to the exposed paddle directly under the IC.
3 ISET
Charge-Current Program and Fast-Charge Current Monitor. Output current from ISET is 877.2µA per
ampere of battery charging current. Set the charging current by connecting a resistor (R2 in Figure 3)
from ISET to GND. I
FAST-CHARGE
= 1596V / R
ISET
. To configure the MAX8814 as a USB charger, see
Figure 4.
4 ABI
Autobooting External Input. See the Autobooting Assistant section and Table 1 for autobooting
conditions. ABI is pulled to GND through an internal 200kΩ resistor.
5 ABO
Autobooting Logic Output. See the Autobooting Assistant section and Table 1 for autobooting
conditions.
6 EN
Logic-Level Enable Input. Drive EN high to disable charger. Drive EN low or leave unconnected for
normal operation. EN has an internal 200kΩ pulldown resistor.
7 POK
Input-Voltage Status Indicator. Connect a 1MΩ pullup resistor from POK to an external system supply.
POK is an open-drain output that asserts low when V
IN
> 4.25V and (V
IN
- V
BATT
) ≥ 40mV. If V
BATT
≥
(V
IN
- 40mV), the IC is shut down and POK becomes high impedance.
8 BATT Battery Connection. Bypass BATT to GND with a minimum of 2.2µF of capacitor.
—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.