AS3607 datasheet(24/71 Pages) AMSCO

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AS3606 AS3607 2v2

Data Sheet - D e t a i l e d D e s c r i p t i o n - P o w e r M anage ment F uncti ons

Figure 13. Charger States

8.4.1 Soft Charge/Trickle Charge

If the battery and therefore VBATSW is below 3V the charger is working in a fixed soft charge mode with a smaller trickle charging current of 24-

265mA. After reaching the 3V level the charger switches to the constant current mode with the programmed charging current.

8.4.2 End of Charge Detection

For the EOC level 4 presets can be selected. This makes it possible to monitor the charging progress also during constant voltage mode. If the

EOC level is reached an interrupt can be generated, but it is also possible to poll the charger status bits at any time.

8.4.3 VSUPSW and Temperature Supervision

The charger will automatically reduce the charging current if VSUPSW drops below the selected level. It will automatically stop charging when

the chip temperature gets too to hot. The charger will return to normal operation as defined in the charger registers if VSUPSW and the chip

temperature return to their normal operating range.

8.4.4 Battery Temperature Supervision

This charger block also features a supply for an external NTC resistor to measure the battery temperature while charging. If the temperature is

too high (voltage on BATTEMP pin is below VBATTEMP_ON) the charger will stop operation. If needed an interrupt can be generated based on

this event. When the battery temperature drops the charger the voltage on BATTEMP pin will rise above VBATTEMP_OFF and the charger will

start charging again. This is forming a temperature hysteresis of about 3 to 5°C to avoid an oscillation of the charger.

The levels for switching off the charger (45ºC or 55ºC) as well as the type of NTC (10k or 100k) can be selected via register settings. The battery

temperature supervision via the NTC can be switched off (NTC_ON = 0).

The supply for the NTC will be only on when a charger is detected and NTC_ON bit is set.

8.4.5 No Battery Detection

If the charger state machine reaches EOC 2 times within a very short period it assumes that there is no battery connected to the VBATSW

terminal.

After this a sensing current of 1uA is applied to the BATTEMP pin to detect if a battery is reconnected.

AS3607 Datasheet(PDF) 24 Page - ams AG