ML4895

Extended al T Commerci 70˚C -20˚C to ent d Equipm le Handhel for Portab ING FEATURem ange perature R August 1996 PRELIMINARY ML4895 Synchronous Buck Controller GENERAL DESCRIPTION The ML4895 synchronous buck controller has been designed to provide high efficiency DC/DC conversion for portable products. The ML4895 can deliver a user programmable 2.5V to 4V output from input voltages of 5.9V to 15V. The ML4895 drives external P- and N-channel MOSFETs in a synchronous buck topology, allowing an overall conversion efficiency of greater than 90% over an output current range exceeding three decades, with an output current capability of up to 5A. The regulator can be disabled via the SHDN pin. While disabled, the output of the regulator is completely isolated from the circuit’s input supply, and the supply current is reduced to less than 5µA to help extend battery life. FEATURES s s s s Regulation to ±3% maximum Adjustable output synchronous buck (2.5V to 4V) Wide input voltage range (5.9V to 15V) Power conversion efficiencies of >90% over 3 decades of output current Integrated antishoot-through logic Shutdown control provides load isolation and minimum sleep mode power consumption Low shutdown current s s s BLOCK DIAGRAM 8 VIN P DRV 7 + VIN 5.9V - 15V 1 VREG BUCK REGULATOR N DRV 6 BIAS CIRCUITS ISENSE 3 VOUT 2.5V - 4V 5 GND – VFB 2 FROM SYSTEM POWER MANAGEMENT SHDN 4 SLEEP LOGIC 1 ML4895 PIN CONFIGURATION ML4895 8-Pin SOIC (S08) VREG VFB ISENSE SHDN 1 ...