STEVAL-ISA082V1 STMicroelectronics

S T E VA L - I S A 0 8 2 V 1 3 A peak 800 kHz fixed-frequency PWM synchronous step-down evaluation board with enable on/off based on the ST1S40IPHR Data brief Description The STEVAL-ISA082V1, based on the ST1S40IPHR, is an internally compensated 800 kHz fixed-frequency PWM synchronous stepdown converter evaluation board. The ST1S40 operates from 4.0 V to 18.0 V input, while it regulates an output voltage as low as 0.8 V and up to VIN (100% duty cycle). The ST1S40 integrates a 95 m high-side switch and a 69 m synchronous rectifier allowing very high efficiency with very low output voltage. The peak current mode control with internal compensation delivers a very compact solution with a minimum component count. The ST1S40 is protected through cycle-by-cycle Features current limiting in case of overload and is also Input voltage Vin = 4 V to 18 V protected by a current foldback function with Output voltage Vout = 3.3 V frequency reduction in case of short-circuit. Maximum output current: 3 A The device is available with an enable on/off Switching frequency: 800 kHz function. Short-circuit protected RoHS compliant October 2015 DocID022276 Rev 2 1/4 www.st.com For further information contact your local STMicroelectronics sales office Schematic diagram STEVAL-ISA082V1 1 Schematic diagram Figure 1: Circuit schematic L 3.3H VOUT (3.3V) VIN (12V) SW VINSW VINA Cin a R1 ST1S40 EN/PG 0.1 1 F FB Cout Cin sw R2 PGND/AGND 22F 10 F GSPG1410151545SG 2/4 DocID022276 Rev 2