M62244FP
Description of operation
The detection times given in this section are for Tchg = 240 minutes.
The voltage values are all typical values.
The charge-current values are for RS = 0.2 Ω.
1. Detecting the adapter-voltage
When an adapter is connected, the voltage from the adapter is the Vcc-pin voltage for the power supply of the IC.
Detection of the adapter voltage thus takes the form of monitoring of the Vcc-pin voltage; when this voltage
departs from the specified range, charging stops, and the standby state (adapter-voltage standby mode) is entered.
Detection is used to set up the following conditions.
When the adapter voltage falls:
(1) When charging has stopped (adapter-detection voltage 1)
(a) If Vcc > 5.2 V, the IC enters the charging-enabled state.
(b) When Vcc ≤ 5.2 V, the IC enters the corresponding charge-standby state (adapter-voltage standby, L mode).
(2) During charging (adapter-detection voltage 2)
(a) As long as Vcc > 4.95 V, charging is continued.
(b) When Vcc ≤ 4.95 V, the IC enters the corresponding charge-standby state (adapter-voltage standby, L
mode).
When the adapter voltage rises:
(1) When Vcc ≥ 6.3 V, the IC enters the corresponding charge-standby state (adapter-voltage standby, H mode).
(2) When Vcc ≤ 6.1 V, the IC returns to the normal state.
Charging stops in adapter-voltage standby L mode, and the LEDs retain the states they had before the mode
transition.
Charging stops in adapter-voltage standby H mode, but in this case LED1 blinks, and LED2 is turned off.
On normal resumption from either of the above modes, the system returns to the state before the mode transition.
Triggering of resets:
(1) When Vcc ≤ 2.6 V, operation of the IC is terminated (outside the operating range).
(2) When Vcc ≥ 2.8 V, the IC starts operation from the reset state.
2. Detecting a connected battery
The IC uses the conditions below to test for battery connection. The conditions are designed for use with batteries
in battery packs that do not include thermistor pins.
(1) Either of the following conditions is assumed to indicate that a battery is connected.
(a) Detection of a battery voltage of 1.0 V or more
(b) During application of precharge 1 for 400 ms, the battery-voltage never rises above 4 V.
(2) Either of the following conditions is assumed to indicate the absence of a battery.
(a) During charging
Charging current remains at or below 100 mA (when the Ifull pin is open), and the battery voltage remains
at or below 1.0 V when the charge-switch is turned off every 400 ms.
(b) When charging has stopped
Battery-voltage is 1.0 V or less, and the battery voltage becomes 4 V or more after the 10-ms charge-switch
is turned on.
Rev.1.0, Sep.19.2003, page 11 of 17
RENESAS [ RENESAS TECHNOLOGY CORP ]
