L5973AD

L5973AD 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 kHz 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 ■ Computer: 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 RthJA 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 kHz to minimize the size of external components. Having a minimum inpu...