Description
PM6685 is a dual step-down controller specifically designed to provide extremely high efficiency conversion, with lossless current sensing technique. The constant on-time architecture assures fast load transient response and the embedded voltage feed-forward provides nearly constant switching frequency operation. An embedded integrator control loop compensates the DC voltage error due to the output ripple.

FEATUREs
■ CONSTANT ON TIME TOPOLOGY ALLOWS VERY FAST LOAD TRANSIENTS
■ 6V TO 28V INPUT VOLTAGE RANGE
■ FIXED 5V-3.3V OUTPUT VOLTAGES
■ 5V AND 3.3V ALWAYS VOLTAGES AVAILABLE DELIVER 100mA PEAK CURRENT
■ 1.23V ± 1% REFERENCE VOLTAGE AVAILABLE
■ NO RSENSE CURRENT SENSING USING LOW SIDE MOSFETs’ RDS(on)
■ ACCURATE CURRENT SENSE WITH RSENSE
■ NEGATIVE CURRENT LIMIT
■ SOFT START INTERNALLY FIXED AT 2ms
■ SOFT OFF FOR OUTPUT DISCHARGE
■ LATCHED OVP AND UVP
■ SELECTABLE PULSE SKIPPING AT LIGHT LOADS
■ SELECTABLE MINIMUM FREQUECY (25kHz) IN PULSE SKIP MODE
■ 4 mW MAXIMUM QUIESCENT POWER
■ INDIPENDENT POWER GOOD SIGNALs
■ OUTPUT VOLTAGE RIPPLE COMPENSATION

APPLICATIONs
■ NOTEBOOK COMPUTERS
■ TABLET PC OR SLATES
■ MOBILE SYSTEM POWER SUPPLY
■ 3-4 CELLS Li+ BATTERY POWERED DEVICES