New Industry Products

Semtech Expands Buck Converter Platform with 3.5MHz, 500mA Synchronous Device with 15 Digitally Controlled Output Voltages

February 01, 2010 by Jeff Shepard

Semtech Corp. announced the SC195, a highly integrated 500mA synchronous step-down (buck) regulator with the tiny size and output flexibility needed for low voltage point-of-load regulation, as well as mobile device applications.

The 1.5 x 1.5mm (0.6mm max. height) SC195 operates from inputs of 2.9V to 5.5V and provides 15 pin-programmable output voltages from 0.8V to 3.3V, covering all the typical core and I/O voltage rails with one device. The 3.5MHz PWM operation balances high efficiency (up to 94%) and fast transient response with small external components. Automatic PSAVE operation reduces quiescent current to 38µA typical at light loads. The SC195 includes a 0.1µA typical shutdown mode.

To set the output voltage, the SC195 utilizes four digital programming pins to eliminate external feedback components, thereby saving space, increasing reliability and eliminating the inventory overhead of stocking individual fixed output voltage regulators for each different load. In applications such as graphics or other processors where voltage levels change on the fly, the programming pins can be driven from the host controller to dynamically position the output voltage level.

With the SC195’s fully-integrated feedback network and internal loop compensation, a complete solution requires only three external components: two small ceramic input/output capacitors and a 1uH inductor. Due to the 3.5MHz switching frequency, multi-layer shielded inductors are very suitable, making it possible to build the complete solution in less than 15mm² PCB footprint with a very thin sub-millimeter profile.

"The SC195 gives our customers an excellent solution for critical power regulation – one that fits into designs where board space, high efficiency, low-power standby operation, flexibility, reduced inventory overhead, reliability and performance are necessary," said Karl Volk, Semtech Director of Marketing for Handheld Power. "The SC195 builds on Semtech’s extensive buck converter family, adding another green power converter with low-current capability and a unique blend of highly optimized features that bring real value."

For increased system reliability, the SC195 has built-in soft-start, over-voltage protection, over-temperature protection, foldback current limit, short-circuit protection, under-voltage lockout and floating programming pin protection. Fast transient response protects sensitive downstream ICs from excessive supply voltage variations. 100% duty-cycle operation is also supported for applications with low headroom between input and output.

The SC195 is available in 1.5 x 1.5mm lead-free 8-pin MLPQ-UT package, is halogen-free and complies with the European Union’s Restriction on Hazardous Substances in Electrical and Electronic Equipment (RoHS) directive to meet worldwide environmental and regulatory requirements.

The SC195 is priced at $0.69 each in 3,000-piece lots and is available immediately in production quantities. An evaluation board is also available.