Synchronous Converter Suits Portable Applications

Linear Technology's LTC3542 is a high-efficiency, 2.25-MHz, synchronous buck regulator that delivers up to 500 mA of continuous output current from either a 2-mm x 2-mm DFN or ThinSOT package.

Dec. 6, 2006

2 min read

Linear Technology’s LTC3542 is a high-efficiency, 2.25-MHz, synchronous buck regulator that delivers up to 500 mA of continuous output current from either a 2-mm x 2-mm DFN or ThinSOT package. Using a constant-frequency, current-mode architecture, the LTC3542 operates from an input voltage range of 2.5 V to 5.5 V, making it ideal for single cell Li-ion/Polymer, or multicell Alkaline/NiCad/NiMH applications.

It can generate output voltages as low as 0.6 V, enabling it to power the latest generation of low-voltage DSPs and microcontrollers. The LTC3542 uses internal switches with an R_DS(ON) of only 0.35 Ω (N-Channel) and 0.50 Ω (P-Channel) to deliver efficiencies as high as 96%. It also utilizes low dropout 100% duty cycle operation to allow output voltages equal to V_IN, further extending battery run-time.

The LTC3542 utilizes Low Ripple (<20 mV_PK-PK) Burst Mode operation to offer only 26 μA of no-load quiescent current. If the application is noise sensitive, Burst Mode operation can be replaced with an even lower noise pulse-skipping mode. The device maintains shutdown currents of less than 1 μA.

The LTC3542's switching frequency is synchronizable to an external clock between 1 MHz and 3 MHz. Other features include ±2% output voltage accuracy.

The LTC3542EDC is offered in a 2-mm x 2-mm DFN-6 package and the LTC3542ES6 is packaged in a 6-Lead ThinSOT package. Both are available from stock. Pricing starts at $1.75 each for both parts in 1000-piece quantities.