STEVAL-ISA043V2 1.5 A /1.2 V high-frequency synchronous buck converter demonstration board based on the ST1S06 Data brief Features ■ Adjustable current-mode pulse width modulation (PWM) synchronous, step-down DC-DC converter with inhibit function ■ Input voltage, Vin: 2.5 V to 5.5 V ■ Output voltage, Vout: 3.3 V ■ Output current, Iout: 1.5 A ■ Switching frequency: 1.5 MHz ■ RoHS compliant Description This demonstration board, based on the ST1S06, is an adjustable current-mode PWM synchronous, step-down DC-DC converter with inhibit function. It is optimized for powering all low-voltage applications and, more generally, to replace the high-current linear solution when the power dissipation may cause overheating of the application environment. It provides up to 1.5 A over an input voltage range of 2.5 V to 5.5 V. STEVAL-ISA043V2 The constant-frequency, current-mode, PWM architecture and stable operation with ceramic capacitors results in a low, predictable output ripple. To clamp the error amplifier reference voltage, this device includes a soft-start control block generating a voltage ramp. The ST1S06 is available in a 6L-DFN 3x3 package. A high switching frequency (1.5 MHz) enables the use of tiny surface-mounted components (SMD). In addition to the resistor divider used to set the output voltage value, only an inductor and two capacitors are required. Moreover, low output ripple is guaranteed by the current-mode PWM topology and by the use of low series resistance (ESR) SMD ceramic capacitors. The device is thermal protected and current limited to prevent damage due to accidental short circuits. It is a complete 1.5 A switching regulator with its internal compensation eliminating the need for additional components. November 2010 Doc ID 18212 Rev 1 For further information contact your local STMicroelectronics sales office. 1/4 www.st.com 4 Circuit schematic STEVAL-ISA043V1 1 Circuit schematic Figure 1. Circuit schematic 6IN 6).?! 6).?37 ).( , ( 343 37 6OUT6 '.$ 6&" # & 2 + 2 + 2/4 Doc ID 18212 Rev 1 # & STEVAL-ISA043V1 2 Revision history Revision history Table 1. Document revision history Date Revision 10-Nov-2010 1 Changes Initial release. Doc ID 18212 Rev 1 3/4 STEVAL-ISA043V1 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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