3.3V/5V/12V Outputs High-Effi ciency Switching Regulators with LM78xx Pinouts

Murata Power Solutions’ 7805SR-C (5V output), 7812SR-C (12V output) and 7803SR-C (3.3V output) step-down switching regulators are modern drop-in replacements for older, ineffi cient, LM7805 and LM7812 linear regulators. The 78XXSRs are pin- and size-compatible with industry-standard TO-220 SIP packages. A 260kHz switching frequency provides for effi ciencies as high as 95. Full-load (up to 0.5A) operation from 9V, 12V, 24V, or 36V supplies at ambient temperatures up to +70°C requires no heat sinks, no temperature derating, no forced-air cooling, and no external capacitors.

FEATURES

■ 3.3V/0.5A, 5V/0.5A or 12V/0.4A outputs; Pin and size-compatible with LM7805 & LM7812 regulators

■ Up to 95 effi ciency – no heat sinks or thermal derating required

■ Two SIP-packages fi t existing TO-220 footprints:

- Vertical-pin models occupy less than 0.1 square in.

- Optional horizontal pins provide 0.350 in. installed height

■ +7.5-36Vdc operating input range; Low 3mA quiescent current

■ Built-in fi lter capacitors – no external components required

■ –40 to +70°C operation at full load; Short-circuit protection Excellent load (±0.2) and line (±0.3) regulation

■ Ideal for powering instrumentation from 9V/12V/24V/28V supplies or batteries

■ Can be used with unregulated dc supplies protection