High Power Step-Down Synchronous DC/DC Controllers for Low Voltage Operation

The LTC3830/LTC3830-1 are high power, high efficiency switching regulator controllers optimized for 3.3V-5V to 1.xV-3.xV step-down applications. A precision internal reference and feedback system provide ±1% output regulation over temperature, load current and line voltage variations. The LTC3830/LTC3830-1 use a synchronous switching architecture with N-channel MOSFETs. Additionally, the chip senses output current through the drain-source resistance of the upper N-channel FET, providing an adjustable current limit without a current sense resistor.

The LTC3830/LTC3830-1 operate with an input supply voltage as low as 3V and with a maximum duty cycle of >91% over temperature. They include a fixed frequency PWM oscillator for low output ripple operation. The 200kHz free-running clock frequency can be externally adjusted or synchronized with an external signal from 100kHz to 500kHz. In shutdown mode, the LTC3830 supply current drops to <10µA. The LTC3830-1 differs from the LTC3830 S8 version by replacing shutdown with a soft-start function.

For a similar, pin compatible DC/DC converter with an output voltage as low as 0.6V, please refer to the LTC3832.

Applications

* CPU Power Supplies

* Multiple Logic Supply Generator

* Distributed Power Applications

* High Efficiency Power Conversion

* High Power Switching Regulator Controller for 3.3V-5V to 1.xV-3.xV Step-Down Applications

* No Current Sense Resistor Required

* Low Input Supply Voltage Range: 3V to 8V

* Maximum Duty Cycle >91% Over Temperature

* All N-Channel External MOSFETs

* Excellent Output Regulation: ±1% Over Line, Load and Temperature Variations

* High Efficiency: Over 95% Possible

* Adjustable or Fixed 3.3V Output (16-Pin Version)

* Programmable Fixed Frequency Operation: 100kHz to 500kHz

* External Clock Synchronization

* Soft-Start (16-Pin Version and LTC3830-1)

* Low Shutdown Current: <10µA

* Overtemperature Protection

* Available in S8, S16 and SSOP-16 Packages