Synchronous Switching Buck Controllers Deliver Up to 12A October 20, 2008
Targeting communications and industrial systems, the SIMPLE SWITCHER family of synchronous buck controllers includes four devices and provides up to 12A of output current. The LM3150 features an adjustable switching frequency and output voltage while the LM3151, LM3152, and LM3153 feature a range of fixed frequencies along with a fixed 3.3V output voltage. Input voltages range from 6V to 42V with an output current capability up to 12A. Requiring minimal external components, the controllers feature a 93% peak efficiency at load. Each employs a constant-on-time control topology that eliminates the need for an external compensation network and patent-pending emulated ripple-mode technology that allows the use of low equivalent-series-resistance output capacitors. The LM3150 controller features an adjustable output voltage down to 0.6V and a programmable operating frequency up to 1 MHz. The LM3151, LM3152, and LM3153 controllers feature fixed-frequencies of 250 kHz, 500 kHz, and 750 kHz, respectively. Each delivers a fixed 3.3V output voltage with a varying input voltage from 6V to 42V and requires 11 external components. Available in 14-pin TSSOPs, the LM3150, LM3151 and LM3152 cost $2.30 each/1,000 and the LM3153 is $2.22 each/1,000. NATIONAL SEMICONDUCTOR CORP., Santa Clara, CA. (800) 272-9959.
