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 STEVAL-ISA043V2 This demonstration board, based on the ST1S06, is an adjustable current-mode PWM synchronous, step-down DC-DC converter with inhibit function. The constant-frequency, current-mode, PWM It is optimized for powering all low-voltage architecture and stable operation with ceramic applications and, more generally, to replace the capacitors results in a low, predictable output high-current linear solution when the power ripple. To clamp the error amplifier reference dissipation may cause overheating of the voltage, this device includes a soft-start control application environment. block generating a voltage ramp. It provides up to 1.5 A over an input voltage range The ST1S06 is available in a 6L-DFN 3x3 of 2.5 V to 5.5 V. 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 1/4 For further information contact your local STMicroelectronics sales office. www.st.com 4 Circuit schematic STEVAL-ISA043V1 1 Circuit schematic Figure 1. Circuit schematic 6I N 6) . 6) . 3 7 , 34 3 ( ). ( 37 6O UT 6 . 6& 2 + & 2 & + 2/4 Doc ID 18212 Rev 1