Date: 28/01/2009

Synchronous buck regulator delivering 2.5Amps of current

The power efficient LTC3603 is a 3MHz synchronous buck regulator from Linear technology uses a constant frequency, current mode architecture. It can deliver up to 2.5A of continuous output current at low output voltages of 0.6V from a 4mm x 4mm QFN or a thermally enhanced MSOP-16 package. The LTC3603 operates from an input voltage of 4.5V to 15V, making it suitable for dual cell Li-Ion applications as well as 12V fixed rail systems. Its switching frequency is user programmable from 300kHz to 3MHz, enabling the use of tiny low cost capacitors and inductors.

The LTC3603 uses internal switches with RDS(ON) of 45mOhms and 85mOhms to deliver efficiencies up to 95%. It is capable of low dropout 99% duty cycle operation to allow output voltages very close to VIN. No load quiescent current is 75uA and less than 1uA in shutdown. An adjustable Burst Mode clamp can be programmed to maximize light load efficiency, making it well-suited for applications that demand maximum battery run-time. For applications that require the lowest noise possible, the LTC3603 can be configured to run in forced continuous mode reducing noise and potential RF interference. Additional features include a Power Good voltage monitor, external synchronization capability and thermal protection.

Other features:

1. 0.6V ±1% Reference Allows Precise, Low Output Voltages
2. Synchronizable to External Clock
3. Power Good Output Voltage Monitor
4. Overtemperature Protection
5. Overvoltage Protection
6. Industrial grade versions Operate over the -40°C to 125°C operating junction temperature range

Package: 16-Lead Exposed MSOP and 4mm × 4mm QFN Packages

Availability: Now in volumes

Price: Commercial grade starts at $3.80 each in 1,000-piece quantities, industrial are priced at $4.47 each in 1,000-piece quantities