FP8103 datasheet(11/19 Pages) FEELING

11 / 19 page

FP8103

This datasheet contains new product information.

Feeling Technology reserves the rights to modify the product specification without notice.

No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.

Website: http://www.feeling-tech.com.tw

Rev. 0.70

11/19

Charge Termination

A charge cycle is terminated when the charge current falls to 1/10 the programmed value after

the final float voltage is reached. This condition is detected by using an internal, filtered comparator to

monitor the PROG pin. When the PROG pin voltage falls below 100mV for longer then TTERM (1.8ms),

charging is terminated. The charge current is shut off and the FP8103 enters standby mode, where the

input supply current drops to 55uA. The FP8103 draws no current from the battery in standby mode.

This feature reduces the charge and discharge cycles on the battery, further prolong the battery life.

Thermal Protection

An internal thermal feedback loop reduces the programmed charge current if the die temperature

rises above a preset value of approximately 145°C. This feature protects the FP8103 from excessive

temperature and allows the user to push the limits of the power handing capability of a given circuit

board without risk of damaging the FP8103. The charge current can be set according to typical

ambient temperature with the assurance that the charge will automatically reduce the current in worst

case condition.

Battery Temperature Fault Monitoring

In the event of a battery over-temperature condition, the charging control will turn off the internal

pass device and report a battery temperature fault on the TEMP pin. Inside the FP8103, two internal

voltage references VTEMP-H and VTEMP-L are fixed at 80% ×VCC and 45% ×VCC respectively. As the

TEMP pin voltage rises above VTEMP-H or falls below VTEMP-L, the FP8103 stops charging and indicates

a fault condition. After the system recovers from a temperature fault, the device will resume charging

operation. For applications that do not need to monitor the battery temperature, short the TEMP pin to

the GND.

The values of R1 and R2 are set according to the battery temperature range and the value of

thermal sensitive resistor. If the battery is equipped with NTC(Negative Temperature Coefficient)

thermistor and the temperature monitor range is TL~TH(TL< TH), then RT, the thermistor resistance,

decreases as temperature increases from TL to TH, means RTL>RTH.

The TEMP pin voltage can be calculated as:

Vcc

TEMP







Thus, this VTEMP decreases as the temperature increase from TL to TH.

To set proper R1 and R2 value for temperature protection, we set:

FP8103 Datasheet(PDF) 11 Page - Feeling Technology Corp.