Description

Micro PMU with 800 mA Buck, 300 mA LDO, Supervisory, Watchdog, and Manual Reset Features: Input voltage range: 2.3 V to 5.5 V One 800 mA buck regulator One 300 mA LDO 20-lead, 4 mm × 4 mm LFCSP package Initial regulator accuracy: ±1% Overcurrent and thermal protection Soft start Undervoltage lockout Open-drain processor reset with threshold monitoring ±1.5% threshold accuracy over the full temperate range Guaranteed reset output valid to VCC = 1 V Dual watchdog for secure systems Watchdog 1 controls reset Watchdog 2 controls reset and regulators power cycle Buck regulator key specifications Current-mode topology for excellent transient response 3 MHz operating frequency Uses tiny multilayer inductors and capacitors Mode pin selects forced PWM or auto PFM/PSM modes 100% duty cycle low dropout mode LDO key specifications Low VIN from 1.7 V to 5.5 V Stable with1 μF ceramic output capacitors High PSRR, 60 dB up to 1 kHz/10 kHz Low output noise Low dropout voltage: 150 mV at 300 mA load −40°C to +125°C junction temperature range