STEVAL-ISA042V1 1.5 A / 1.2 V step-down DC-DC converter demonstration board based on the ST1S03 Data brief as the use of a resistor divider to set the output voltage value. Only an inductor, a Schottky diode, and two capacitors are required. In addition, a low output ripple is guaranteed by the current-mode PWM topology and by the use of low ESR SMD ceramic capacitors. It is thermally protected and current limited to prevent damage due to accidental short-circuits. The ST1S03 is available in a DFN6 (3x3 mm) package. STEVAL-ISA042V1 Features * Adjustable current-mode PWM step-down DCDC converter * Output voltage, Vout: 1.2 V * Output current, Iout: 1.5 A * Internal compensation to eliminate additional components * Pulse skipping for Iout lower than 15 mA, to maintain the regulation with light loads * RoHS compliant Description The STEVAL-ISA042V1 demonstration board is a step-down DC-DC converter based on ST's ST1S03 switching regulator, optimized for powering the low-voltage digital core in HDD applications and, more generally, replacing the high-current linear solution when the power dissipation may cause excessive heating of the application environment. It provides up to 1.5 A over an input voltage range of 3 V to 16 V. A high switching frequency (1.5 MHz) allows the use of tiny surface-mounted components, as well May 2013 DocID024676 Rev 1 For further information contact your local STMicroelectronics sales office. 1/4 www.st.com 4 Circuit schematic 1 STEVAL-ISA042V1 Circuit schematic Figure 1. STEVAL-ISA042V1 demonstration board schematic $09 2/4 DocID024676 Rev 1 STEVAL-ISA042V1 2 Revision history Revision history Table 1. Document revision history Date Revision 21-May-2013 1 Changes Initial release. DocID024676 Rev 1 3/4 STEVAL-ISA042V1 Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries ("ST") reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST's terms and conditions of sale. Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no liability whatsoever relating to the choice, selection or use of the ST products and services described herein. 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