Features
 Step-down current mode PWM (1.5 MHz) DC-DC converter
 2% DC output voltage tolerance
 Internal soft-start for STARTUP current limitation and power on delay of 50 - 100 μs
 Typical efficiency: > 70% over all operating conditions
 1.5 A output current capability
 Not switching quiescent current: max 2.5 mA over temperature range
 Switch VDS: max. 350 mV at ISW = 750 mA
 Uses tiny capacitors and inductors
 Available in DFN6D 3 x 3 mm package with exposed pad

Description
The ST1S03 is a step-down DC-DC converter optimized for powering a low voltage digital core in HDD applications and, generally, to replace the high current linear solution when the power dissipation may cause a high 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-mount components: as well as the resistor divider to set the output voltage value, only an inductor, a Schottky diode and two capacitors are required. Besides, a low output ripple is guaranteed by the current mode PWM topology and by the use of low ESR SMD ceramic capacitors. The device is thermal protected and current limited to prevent damages due to an accidental short-circuit. The ST1S03 device is available in a DFN6D package.