ACE4704
Fully 5A, 4cell Standalone Li-ion Battery Charger
End-of-Charge Current Setting
End-of-charge current can be set by connecting a resistor from EOC pin to GND, and is decided by the
following equation:
I
EOC
=1.278*(14,350+Rext) / RCS*10
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Where:
I
EOC
is the end-of-charge current in Ampere
Rext is the external resistance from EOC pin to GND in Ω. Rext can not be great than 100KΩ,
otherwise the charging may not be terminated correctly.
R
CS
is the current sense resistance between CSP pin and BAT pin in Ω
It is our interest to calculate the ratio between I
EOC
and I
CH
:
When Rext=0Ω, the minimum I
EOC
/I
CH
=9.17%
When Rext=100KΩ, the maximum I
EOC
/I
CH
=73%
Automatic Battery Recharge
After the charge cycle is completed and both the battery and the input power supply (wall adapter) are
still Connected, a new charge cycle will begin if the battery voltage drops below 16V due to self-discharge
or external loading. This will keep the battery capacity at more than 80% at all times without manually
restarting the charge cycle.
Battery Temperature Monitoring
A negative temperature coefficient (NTC) thermistor located close to the battery pack can be used to
monitor battery temperature and will not allow charging unless the battery temperature is within an
acceptable range. Connect a 10kΩ thermistor from the TEMP pin to ground. Internally, for hot
temperature, the low voltage threshold is set at 175mV which is equal to 50℃(RNTC≈3.5kΩ). For cold
temperature, the high voltage threshold is set at 1.61V which is equal to 0℃(RNTC≈32kΩ) with 50uA of
pull-up current.
Once the temperature is outside the window, the charge cycle will be suspended, and the charge cycle
resumes if the temperature is back to the acceptable range.
VER 1.2
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ACE [ ACE TECHNOLOGY CO., LTD. ]
