LTC1775

LTC1775 High Power No RSENSE Current Mode Synchronous Step-Down Switching Regulator TM FEATURES s s s s s s s s s s s s s s s s s DESCRIPTIO Highest Efficiency Current Mode Controller No Sense Resistor Required 300mV Maximum Current Sense Voltage Stable High Current Operation Dual N-Channel MOSFET Synchronous Drive Wide VIN Range: 4V to 36V Wide VOUT Range: 1.19V to VIN ± 1% 1.19V Reference Programmable Fixed Frequency with Injection Lock Very Low Drop Out Operation: 99% Duty Cycle Forced Continuous Mode Control Pin Optional Programmable Soft Start Pin Selectable Output Voltage Foldback Current Limit Output Overvoltage Protection Logic Controlled Micropower Shutdown: IQ < 30µA Available in 16-Lead Narrow SSOP and SO Packages The LTC®1775 is a synchronous step-down switching regulator controller that drives external N-channel power MOSFETs using few external components. Current mode control with MOSFET VDS sensing eliminates the need for a sense resistor and improves efficiency. Largely similar to the LTC1625, the LTC1775 has twice the maximum sense voltage for high current applications. The frequency of a nominal 150kHz internal oscillator can be synchronized to an external clock over a 1.5:1 frequency range. Burst ModeTM operation at low load currents reduces switching losses and low dropout operation extends operating time in battery-powered systems. A forced continuous mode control pin can assist secondary winding regulation by disabling Burst Mode operation when the m...