SLUSCJ4B June 2017 – March 2022 BQ25600 , BQ25600D
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 0.5 or approximately 0.5. Usually inductor ripple is designed in the range between 20% and 40% maximum charging current as a trade-off between inductor size and efficiency for a practical design.