A4059
BATTERY MANAGEMENT
AiT Semiconductor Inc.
www.ait-ic.com
PROGRAMMABLE VOLTAGE AND
CURRENT LINEAR BATTERY MANAGEMENT CHIP
DETAILED INFORMATION
Application Information
Set constant voltage charging voltage
Through an external resistor, the output voltage can be set , taking into account the accuracy requirements ,
it is recommended that the resistor with an accuracy of 1% . Constant voltage charging voltage (VBAT) can be
calculated:
VBAT=VFB×(1+R4 / R3)
Set the charge current
In constant-current mode, formula for calculating charge current: ICH = 1000V / RISET
ICH represents the charge current, units is ampere, RISET represents ISET pin to ground resistance in ohms.
For example, if you need 500mA charge current, according to the following formula:
R
ISET=1000V/0.5A = 2KΩ
In order to ensure good stability and temperature characteristics, RISET recommend the use of 1% precision
metal film resistors. By measuring the ISET pin voltage can be detected charge current. Charge current can
be calculated using the following formula: ICH = (VISET / RISET) × 1000
Battery temperature monitoring
In order to prevent the battery temperature is too high or too low on the battery damage, A4059 internal
battery temperature monitoring of integrated circuits. Battery temperature monitoring is by measuring the
TEMP pin voltage to achieve, TEMP pin voltage is within the battery NTC thermistor and a resistor divider
network.
A4059 the TEMP pin voltage with the chip and the two thresholds VLOW VHIGH compared to confirm whether
the battery temperature exceeds the normal range. In the A4059, VLOW were fixed in 30% × VIN, VHIGH were
fixed in 60% × VIN. If the TEMP pin voltage VTEMP <VLOW or VTEMP> VHIGH, the battery temperature is too high
or too low, charging will be suspended; If the TEMP pin voltage VTEMP VLOW and VHIGH in between, the charge
cycle will continue.
REV1.0 - OCT 2013 RELEASED -
- 7 -
AITSEMI [ AiT Semiconductor ]
