EC49022 datasheet(7/8 Pages) E-CMOS

7 / 8 page

1A, Single Cell Linear Lithium Battery Charger

E-CMOS Corp. (www.ecmos.com.tw)

Page 7 of 8

4J30N Rev. F001

EC49022

Charge termination

A charge cycle is terminated when the charge current falls to 1/10th the programmed value after the final float

voltage is reached. This condition is detected by using an internal filtered comparator to monitor the PROG pin.

When the PROG pin voltage falls below 100mV for longer than tTEMP (typically 1.8mS), Charging is terminated.

The charge current is latched off and the EC49022 enters standby mode, where the input supply current drops to

μA (Note:C/10 termination is disabled in trickle charging and thermal limiting modes).

When charging, transient loads on the BAT pin can cause the PROG pin to fall below 100mV for short periods

of time before the DC charge current has dropped to 1/10th the programmed value. The 1.8mS filter time (tTEMP)

on the termination comparator ensures that transient loads of this nature do not result in premature charge cycle

termination. Once the average charge current drops below 1/10th the programmed value, the EC49022

terminated the charge cycle and ceases to provide any current through the BAT pin. In this state all loads on the

BAT pin must be supplied by the battery.

Charge status indicator

EC49022 has two open-drain status indicator output CHRG and STDBY . CHRG is pull-down when the

EC49022 in a charge cycle. In other status CHRG in high impedance. CHRG and STDBY are all in high

impedance when the battery out of the normal temperature.

Represent in failure state, when TEMP pin in typical connecting, or the charger with no battery: red LED

and

green LED all don’t light. The battery temperature sense function is disabled by connecting TEMP pin to

GND. If battery is not connected to charger, CHRG pin outputs a PWM level to indicate no battery. If BAT pin

connects a

10μF capacitor, the frequency of CHRG flicker about 1-4S, If not use status indicator should set

status indicator output connected to GND.

EC49022 Datasheet(PDF) 7 Page - E-CMOS Corporation