Hello,
I have a charger application with the bq51050B. Everything work well (charging, wireless power Transfer...).
Today I tested my application in a climate chamber to see if the JEITA current reduction works.
Unfortunately my board didn't reduce the charge current by 50% at 45 °C. Temperature rises up to 53 °C and no current reduction happened.
My design uses the same NTC type (ERTJZEG103JA) as in the example calulation of the datasheet.
My schematic uses R1, R3 and C3 as shown in Fig. 29 of the datasheet and the values are:
R1 = 29k4 / R3 = 14k3 as in the example calulation of the datasheet.
I have no external R2 (Fig. 29 of the datasheet) assuming that this 20 kOhm resistor is internally.
Why does the JEITA current reduction don't work?
Could you please give me some hints what could be wrong?
Best regards
Christian Zellner