L5973D

L5973D 2.5 A switch step down switching regulator Features ■ 2.5 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 ■ 250 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: changers, car battery, DC-DC converters Figure 1. Test application circuit HSOP8 exposed pad Description The L5973D is a step down monolithic power switching regulator with a minimum switch current limit of 2.5 A so it is able to deliver more than 2 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(j-amb) down to approximately 40 °C/W. The device uses an internal P-channel D-MOS transistor (with a typical Rdson of 250 mΩ) as switching element to minimize the size of the external components. An internal oscillator fixes the switching frequency at 250 kHz. Having a minimum input voltage of 4 V only, it is particularly su...