Tool/software:
Hi,
I am using the BQ25306 IC to charge a 10,000mAh lithium polymer battery, and I need to set it up to charge at 3A. Based on the datasheet,
I understand the charge current ratio KICHGK_{ICHG}KICHG and the relationship ICHG=KICHGRICHGI_{CHG} = \frac{K_{ICHG}}{R_{ICHG}}ICHG=RICHGKICHG.
I calculated that for a 3A charge current, RICHGR_{ICHG}RICHG should be approximately 13.3kΩ using a KICHGK_{ICHG}KICHG value of 40000 AxΩ.
Given the information from the datasheet:
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For 1.72A Charge Current: RICHG=23.2kΩ
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For 1.0A Charge Current: RICHG=40.2kΩ
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For 0.5A Charge Current: RICHG=78.7kΩ
- Calculating RICHGR_{ICHG}RICHG for 3A Charge Current RICHG=3A40000=13333.33Ω≈13.3kΩ
But try all these resistor for set charge current 3 amp. We get some current near about 1.7amp at 10k resistor value.
- BQ25306 can generate heat due to internal power dissipation.
- Inductors and Capacitors: These components can also generate heat if not selected properly.
- The BQ25306 has a TS (Temperature Sense) pin designed for this purpose. Connect the NTC thermistor between the TS pin and GND.Use a resistor divider network if needed to match the thermistor's characteristics with the TS pin's requirements.So can you share me proper combination of resistance with NTC and without NTC
Could you please verify if this is correct and suggest any additional component recommendations or considerations for achieving a stable 3A charge current?
Schematic PDF.pdf
