This four-phase reference design provides 3.3 VOUT at 24 A from a 3.8-V to 16-V automotive power source. The design uses two LMQ644A2-Q1 dual-channel synchronous buck regulators operating at a nominal switching frequency of 500 kHz. Forced pulse width modulation (FPWM) or pulse frequency modulation (PFM) for light load operation is jumper selectable. Test points are provided for frequency synchronization, power good and frequency response injection.
Features
- Dual-phase integrated-switch regulators for small solution size
- Selectable FPWM or PFM operation at light load
- 3.8-V minimum input for cold cranking
- 500-kHz switching frequency for best size versus efficiency
- Spread spectrum option for low EMI
- Tested to EN 55025 class 5 conducted emissions