78SR series 3.3V/5V/12V outputs high-efficiency switching regulators with LM78XX pinouts
The DATEL 78SR Series datasheet covers the 7803SR, 7805SR and 7812SR high-efficiency step-down switching regulators. These models provide 3.3V/0.5A, 5V/0.5A or 12V/0.4A outputs and are pin- and size-compatible with LM7805 and LM7812 regulators in TO-220 SIP packages. A 260kHz switching frequency provides efficiencies as high as 95%, and full-load operation from 9V, 12V, 24V or 36V supplies at up to +70°C requires no heat sinks, no temperature derating, no forced-air cooling and no external capacitors.
The document includes technical notes, input/output model tables, performance and functional specifications, typical performance curves, ordering information and mechanical specifications. Technical notes cover input/output filtering, input fusing, lack of input-output isolation, overvoltage protection, 40Vdc operation, soldering and handling, horizontal-pin models and dropout voltage.
| Output Voltage | +3.3Vdc, +5.0Vdc, +12.0Vdc |
|---|---|
| Rated Output Current | 0.5A for 7803SR and 7805SR; 0.4A for 7812SR |
| Input Voltage Range | +7.5-36Vdc for 7803SR and 7805SR; +15-36Vdc for 7812SR |
| Quiescent Current | 3mA typical, 5mA maximum |
| Efficiency | Up to 95% |
| Switching Frequency | 260kHz |
| Operating Temperature | -40 to +70°C |
| Storage Temperature | -40 to +85°C |
| Package | Open-frame SIP |
| Weight | 0.08 ounces (2.2g) |
| Pin Soldering | +260°C for 5 seconds |
It provides 3.3V/0.5A, 5V/0.5A or 12V/0.4A outputs.
No; full-load operation at up to +70°C requires no heat sinks and no temperature derating.
No, the internal input and output circuits share a common GND connection, so there is no electrical isolation.
Inputs up to 40Vdc are allowed only with reduced load current, and the input must never exceed 45Vdc.