Analog Devices Inc./Maxim Integrated

The LT1370 is a monolithic high frequency current mode switching regulator. It can be operated in all standard switching configurations including boost, buck, flyback, forward, inverting and "Cuk." A 6A high efficiency switch is included on the die, along with all oscillator, control and protection circuitry.The LT1370 typically consumes only 4.5mA quiescent current and has higher efficiency than previous parts. High frequency switching allows for very small inductors to be used.New design techniques increase flexibility and maintain ease of use. Switching is easily synchronized to an external logic level source. A logic low on the Shutdown pin reduces supply current to 12µA. Unique error amplifier circuitry can regulate positive or negative output voltage while maintaining simple frequency compensation techniques. Nonlinear error amplifier transconductance reduces output overshoot on start-up or overload recovery. Oscillator frequency shifting protects external components during overload conditions.ApplicationsBoost RegulatorsLaptop Computer SuppliesMultiple Output Flyback SuppliesInverting Supplies

The LT1371 is a monolithic high frequency current mode switching regulator. It can be operated in all standard switching configurations including boost, buck, flyback, forward, inverting and "Cuk". A 3A high efficiency switch is included on the die, along with all oscillator, control and protection circuitry.The LT1371 typically consumes only 4mA quiescent current and has higher efficiency than previous parts. High frequency switching allows for very small inductors to be used.New design techniques increase flexibility and maintain ease of use. Switching is easily synchronized to an external logic level source. A logic low on the Shutdown pin reduces supply current to 12µA. Unique error amplifier circuitry can regulate positive or negative output voltage while maintaining simple frequency compensation techniques. Nonlinear error amplifier transconductance reduces output overshoot on start-up or overload recovery. Oscillator frequency shifting protects external components during overload conditions.ApplicationsBoost RegulatorsLaptop Computer SuppliesMultiple Output Flyback SuppliesInverting Supplies

The LT1375/LT1376 are 500kHz monolithic buck mode switching regulators. A 1.5A switch is included on the die along with all the necessary oscillator, control and logic circuitry. High switching frequency allows a considerable reduction in the size of external components.The topology is current mode for fast transient response and good loop stability. Both fixed output voltage and adjustable parts are available.A special high speed bipolar process and new design techniques achieve high efficiency at high switching frequency. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. A shutdown signal will reduce supply current to 20μA on both parts. The LT1375 can be externally synchronized from 580kHz to 900kHz with logic level inputs.The LT1375/LT1376 fit into standard 8-pin PDIP and SO packages, as well as a fused lead 16-pin SO with much lower thermal resistance. Full cycle-by-cycle short-circuit protection and thermal shutdown are provided. Standard surface mount external parts are used, including the inductor and capacitors.For low input voltage applications with 3.3V output, see LT1507. This is a functionally identical part that can operate with input voltages between 4.5V and 12V.ApplicationsPortable ComputersBattery-Powered SystemsBattery ChargerDistributed Power