JAJSKU9B December 2022 – February 2024 BQ25628 , BQ25629
PRODUCTION DATA
The 1.5-MHz switching frequency allows the use of small inductor and capacitor values to maintain an inductor saturation current higher than the charging current (ICHG) plus half the ripple current (IRIPPLE):
The inductor ripple current depends on the input voltage (VVBUS), the duty cycle (D = VBAT/VVBUS), the switching frequency (fS) and the inductance (L).
The maximum inductor ripple current occurs when the duty cycle (D) is approximately 0.5. Usually inductor ripple is designed between 20% and 40% of the maximum charging current as a trade-off between inductor size and efficiency.