ZHCS229C September 2011 – January 2020 BQ24725A
PRODUCTION DATA.
The charger switching frequency can be adjusted ±18% to solve EMI issue via SMBus command. ChargeOption() bit [9]=0 disable the frequency adjust function. To enable frequency adjust function, set ChargeOption() bit[9]=1. Set ChargeOption() bit [10]=0 to reduce switching frequency, set bit[10]=1 to increase switching frequency.
If frequency is reduced, for a fixed inductor the current ripple is increased. Inductor value must be carefully selected so that it will not trig cycle-by-cycle peak over current protection even for the worst condition such as higher input voltage, 50% duty cycle, lower inductance and lower switching frequency.