LTC3537

The LTC®3537 combines a high effi ciency, 2.2MHz step-up DC/DC converter with an idependent 100mA low dropout regulator (LDO). The step-up converter starts from an input voltage as low as 0.68V and contains an internal 0.4 switch and a 0.6 synchronous rectifi er that disconnects from the output when disabled in shutdown. A switching frequency of 2.2MHz minimizes solution footprint by allowing the use of tiny, low profi le inductors and ceramic capacitors.

The current mode PWM design is internally compensated, reducing external parts count. Fixed frequency switching is maintained until a light load current is sensed, at which point Burst Mode® operation is engaged to maximize effi ciency. For low noise operation, Burst Mode Operation can be disabled. Anti-ring circuitry reduces EMI by damping the inductor in discontinuous mode.

Additional features of LTC3537 include a low shutdown current of under 1A and thermal overload protection. The integrated LDO regulator provides a very low noise, programmable low dropout supply.