NCP1835

http://onsemi.com

2

FAULT

CFLG

V2P8

EN

VSNS

BAT

GND

ISEL TIMER

80 k

4.7

mF

GND

15 nF

Microprocessor

4.7

mF

Figure 1. Typical Application Circuit

0.1

mF

PIN FUNCTION DESCRIPTION

Pin

Symbol

Description

1

Input Supply Voltage. Provides power to the charger. This pin should be bypassed with at least a 4.7

mF ceramic

capacitor to ground.

2

FAULT

An open−drain output indicating fault status. This pin is pulled LOW under any fault conditions. A FAULT condition

resets the counter.

3

CFLG

An open−drain output indicating charging or end−of−charge states. The CFLG pin is pulled LOW when the

will be latched until a recharge cycle or a new charge cycle starts.

4

TIMER

TIMEOUT. Trickle Charge has a time limit of 1/8 of the TIMEOUT period.

5

GND

Ground pin of the IC. For thermal consideration, it is recommended to solder the exposed metal pad on the

backside of the package to ground.

6

EN

Enable logic input. Connect the EN pin to LOW to disable the charger or leave it floating to enable the charger.

7

V2P8

2.8 V reference voltage output. This pin outputs a 2.8 V voltage source when an adapter is present. The

maximum loading for this pin is 2.0 mA.

8

ISEL

9

VSNS

Battery voltage sense pin. Connect this as close as possible to the battery input connection.

10

BAT

Charge current output. A minimum 4.7

mF capacitor is needed for stability when the battery is not attached.