LTC1628-PG Datasheet | Linear Technology

LTC1628/LTC1628-PG High Efficiency, 2-Phase Synchronous Step-Down Switching Regulators Features s s s s s s s s s s s s s s s s s DESCRIPTIO U APPLICATIO S s s s s s Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise OPTI-LOOPTM pensation Minimizes COUT Dual N-Channel MOSFET Synchronous Drive ±1% Output Voltage Accuracy Power Good Output Voltage Monitor (LTC1628-PG) DC Programmed Fixed Frequency 150k Hz to 300k Hz Wide VIN Range: 3.5V to 36V Operation Very Low Dropout Operation: 99% Duty Cycle Adjustable Soft-Start Current Ramping Foldback Output Current Limiting Latched Short-Circuit Shutdown with Defeat Option Output Overvoltage Protection Remote Output Voltage Sense Low Shutdown IQ: 20µA 5V and 3.3V Standby Regulators Small 28-Lead SSOP Package Selectable Constant Frequency or Burst Mode TM Operation The LTC®1628/LTC1628-PG are high performance dual step-down switching regulator controllers that drive all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows adjustment of the frequency up to 300k Hz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages out of phase. OPTI-LOOP pensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The precision 0.8V reference and power good output indicator are patible with future microprocessor generations, and a wide 3.5V to 30V (36V maximum) input supply range enpasses all battery chemistries. A RUN/SS pin for each controller provides both soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when overcurrent latchoff is disabled. Output overvoltage protection circuitry latches on the bottom MOSFET until VOUT returns to normal. The FCB mode pin can select among Burst Mode, constant frequency mode and continuous inductor current mode or...