L5973AD Datasheet | STMicroelectronics

2 A switch step down switching regulator Features - 2 A internal switch - Operating input voltage from 4 V to 36 V - 3.3 V / (±2%) reference voltage - Output voltage adjustable from 1.235 V to 35 V - Low dropout operation: 100% duty cycle - 500 k Hz Internally fixed frequency - Voltage feedforward - Zero load current operation - Internal current limiting - Inhibit for zero current consumption - Synchronization - Protection against feedback disconnection - Thermal shutdown Applications - Consumer: STB, DVD, TV, VCR, car radio, LCD monitors - Networking: XDSL, modems, DC-DC modules - puter: printers, audio/graphic cards, optical storage, hard disk drive - Industrial: chargers, car battery, DC-DC converters Figure 1. Test application circuit HSOP8 exposed pad Description The L5973AD is a step down monolithic power switching regulator with a switch current limit of 2 A so it is able to deliver more than 1.5 A DC current to the load depending on the application conditions. The output voltage can be set from 1.235 V to 35 V. The high current level is also achieved thanks to an SO8 package with exposed frame, that allows to reduce the Rth JA down to approximately 40 °C/W. The device uses an internal P-Channel D-MOS transistor (with a typical of 200 mΩ) as switching element to avoid the use of bootstrap capacitor and guarantee high efficiency. An internal oscillator fixes the switching frequency at 500 k Hz to minimize the size of external ponents. Having a minimum input voltage of 4 V only, it is particularly suitable for 5 V bus, available in all puter related applications. Pulse by pulse current limit with the internal frequency modulation offers an effective constant current short circuit protection. VIN = 4V to 35V C1 10μF 35V CERAMIC VREF 3.3V SYNC. P C4 22n F 6 1 8...