for further information contact your local stmicroelectronics sales office. may 2012 doc id 023235 rev 1 1/4 4 STEVAL-ISA101V1 2 a dc step-down switching regulator with 4 v/36 v input voltage range based on the l5973d data brief features v in : 4 v to 36 v v out : 1.235 v to 36 v output current: 2 a dc internal oscillator switching frequency: 250 khz short-circuit protection inhibit and thermal shutdown rohs compliant description the STEVAL-ISA101V1 demonstration board is based on the l5973d, a step-down monolithic switching regulator with 2 a dc (2.5 a switch peak current) current capability over the output voltage range (1.235 v to 36 v). the operating input voltage ranges from 4 v to 36 v. the device is based on bcd5 technology. the embedded power element is a p-channel d-mos transistor so the driving stage does not require any bootstrap capacitor and the duty cycle can range up to 100%. an internal oscillator fixes the switching frequency at 250 khz. a synchronization pin is available when a higher switching frequency (up to 700 khz) is required. pulse-by-pulse current protection and a frequency foldback feature always guarantee an effective short-circuit protection. other features include voltage feed-forward, protection against feedback disconnection, inhibit and thermal shutdown. previous sales code: eval5973d. www.st.com
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