High Input Voltage, Current Mode Boost, Flyback and SEPIC Controller

The LTC1871-7 is a current mode, boost, flyback and SEPIC controller optimized for driving 6V-rated MOSFETs in high voltage applications. The LTC1871-7 works equally well in low or high power applications and requires few components to provide a complete power supply solution. The switching frequency can be set with an external resistor over a 50kHz to 1MHz range, and can be synchronized to an external clock using the MODE/SYNC pin. Burst Mode operation at light loads, a low minimum operating supply voltage of 6V and a low shutdown quiescent current of 10µA make the LTC1871-7 well suited for battery-operated systems. For applications requiring constant frequency operation, Burst Mode operation can be defeated using the MODE/SYNC pin. The LTC1871-7 is available in the 10-lead MSOP package.

VIN Range

INTVCC

Features

LTC1871

2.5V to 36V

5.2V

-

LTC1871-1

2.5V to 36V

5.2V

Lower Burst Mode Threshold (0.195V vs. 0.3V)

LTC1871-7

6V to 36V

7V

Drives 6V Gate N-Channel MOSFETs

LTC1871X

2.5V to 36V

5.2V

175°C Junction Temp, 100% Tested at 175°C

Applications

* Telecom Power Supplies

* 42V Automotive Systems

* 24V Industrial Controls

* IP Phone Power Supplies

* Optimized for High Input Voltage Applications

* Wide Chip Supply Voltage Range: 6V to 36V

* Internal 7V Low Dropout Voltage Regulator Optimized for 6V-Rated MOSFETs

* Current Mode Control Provides Excellent Transient Response

* High Maximum Duty Cycle (92% Typ)

* ±2% RUN Pin Threshold with 100mV Hysteresis

* ±1% Internal Voltage Reference