A4059
BATTERY MANAGEMENT
AiT Semiconductor Inc.
www.ait-ic.com
PROGRAMMABLE VOLTAGE AND
CURRENT LINEAR BATTERY MANAGEMENT CHIP
From the above derivation can be seen to be setting the temperature range and supply voltage VIN is
irrelevant, only with R1, R2, RTH, RTL; one, RTH, RTL can access the relevant manuals or through
experimental test battery be.
In practice, if only one side of the temperature characteristics of concern, such as over-temperature
protection, then R2 can’t and can only R1. R1 derivation becomes very simple, not discussed here
Open-drain output status indication
A4059 has two open-drain status indication sides, CHAG and DONE, the two status indicator LEDs client
can drive or microcontroller port. CHAG used to indicate charging status, charging time, CHAG is low; DONE
to indicate the charging end of the state, when the charging end, DONE is low. When the battery
temperature is outside the normal temperature range more than 0.15 seconds, CHAG and the DONE pin is
high impedance output state.
When the battery charger not received, the charger will quickly charge the output capacitor to the constant
voltage value, as the battery voltage detection the BAT pin input leakage current, the BAT pin voltage will
slowly down to recharge threshold, so the BAT pin voltage is 150mV to form a ripple waveform, while CHAG
output pulse signal that there is no battery installed. When the battery BAT pin external connectors for the
4.7uF capacitor, the pulse period of about 2Hz
The following table lists CHAG and DONE pin status in each case:
State
CHAG
DONE
Charge
Always bright
Always off
Full
Without Battery
Flashing
Error
Always off
Always bright
Always off
Always off
Always bright
NOTE1: CHAG flicker frequency with external capacitor when not connect battery, generally recommended
4.7uF.The greater the capacitance, the smaller frequency flicker.
NOTE2: The error situation: Beyond the operating temperature range (temperature too high or too low), I set
side vacant, VIN <VBAT, VIN <3.8V and so on.
REV1.0 - OCT 2013 RELEASED -
- 9 -
AITSEMI [ AiT Semiconductor ]
