The PowerWise Simple Switcher controller family includes four synchronous buck controllers for communications and industrial systems. The LM3150 features an adjustable switching frequency and output voltage, and the LM3151, LM3152 and LM3153 feature a range of fixed frequencies along with a fixed 3.3V output voltage. 

Input voltages for the controllers range from 6V to 42V with output current capability up to 12A. The controllers require minimal external components, which simplifies the design process and reduces the overall system size. The Simple Switcher controllers feature 93% peak efficiency at load, making them energy efficient. 

Controller designs are more complex than integrated switching system designs due to the challenges associated with selecting external Mosfets. National’s Webench suite of online tools has been expanded to include Mosfet selection and analysis for a quick and easy controller design. 

Technical features of the Simple Switcher synchronous controllers

The four Simple Switcher controllers are easy-to-use components to design an efficient, medium-current, step-down power controller.  The LM3150, LM3151, LM3152 and LM3153 employ a constant-on-time (COT) control topology that eliminates the need for an external compensation network, which reduces external component count and design complexity.

The emulated ripple-mode technology allows for the use of low equivalent-series-resistance (ESR) output capacitors which further reduces system size, complexity and output voltage ripple, providing enhanced electrical performance.

The LM3150 controller features an adjustable output voltage down to 0.6V and programmable operating frequency up to 1 MHz.  For more information on the LM3150 or to order samples and an evaluation board, visit http://www.national.com/pf/LM/LM3150.html.

The LM3151, LM3152 and LM3153 controllers feature fixed-frequencies of 250 kHz, 500 kHz and 750 kHz, respectively, and include output currents up to 12A. Each offer a fixed 3.3V output voltage with varying input voltages from 6V to 42V and require just 11 external components for easy design and small system size.

For more information on the LM3151, LM3152 and LM3153 or to order samples and an evaluation board, visit http://www.national.com/pf/LM/LM3151.html, http://www.national.com/pf/LM/LM3152.html and http://www.national.com/pf/LM/LM3153.html.