data brief for further information contact your local stmicroelectronics sales office. november 2010 doc id 18215 rev 1 1/4 4 STEVAL-ISA052V1 high efficiency step-down cont roller with embedded 2 a ldo regulator demonstration board based on the pm6675s features 4.5 v to 28 v input voltage range 0.6 v, 1 % voltage reference 1.5 v fixed output voltage 0.6 v to 3.3 v adjustable output voltage 1.237 v 1 % reference voltage available very fast load transient response constant on- time loop control no-rsense current sens ing using low-side mosfets? r ds(on) negative current limit latched ovp, uvp and thermal shutdown fixed 3 ms soft-start selectable pulse-skipping at light load selectable no-audible (33 khz) pulse-skip mode all ceramic output capacitors application supported output voltage ripple compensation output soft-end rohs compliant description the STEVAL-ISA052V1 demonstration board is based on the pm6675s device which consists of a single high efficiency step-down controller and an independent low drop-out (ldo) linear regulator. the constant on-time (cot) architecture assures fast transient response supporting both electrolytic and ceramic output capacitors. an embedded integrator control loop compensates the dc voltage error due to the output ripple. selectable low-consumption mode allows the highest efficiency over a wide range of load conditions. the low-noise mode sets the minimum switching frequency to 33 khz for audio-sensitive applications. the ldo lin ear regulator can sink and source up to 2 apk. two fixed current limits (1 a and 2 a) can be chosen. an active soft-end is independently performed on both the switching and the linear regulator outputs when disabled. STEVAL-ISA052V1 www.st.com
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STEVAL-ISA052V1 revision history doc id 18215 rev 1 3/4 2 revision history table 1. document revision history date revision changes 12-nov-2010 1 initial release.
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