7905 IC Fixed15V Negative Voltage Regulator
The LM7915 belongs to the 79xx series of fixed negative voltage regulators. It provides a constant −15V output from a higher negative input voltage source, making it ideal for analog and digital circuits that require negative supply rails.
The regulator operates with an input voltage typically ranging from −17V to −30V, while supporting up to 1A output current under proper heat dissipation conditions. Internal protection features include thermal shutdown, current limiting, and short-circuit protection, which enhance safety and longevity in a wide variety of applications.
Designers often pair the LM7915 with a complementary positive regulator, such as the LM7815, to produce dual-polarity power supplies for audio processing, instrumentation, and industrial control systems. Its ease of use and minimal external components make it a versatile choice for stable −15V regulation.
Pin Configuration (TO-220 Package)
| Pin | Name | Description |
|---|---|---|
| 1 | Ground | Common ground |
| 2 | Input | Negative unregulated voltage |
| 3 | Output | Regulated −15V output |
Key Features
Supplies a fixed −15V output for electronic systems.
Delivers up to 1A current with adequate heatsinking.
Works with inputs down to −30 volts reliably.
Includes thermal overload protection for safe operation.
Limits output current under overload or fault conditions.
Protects circuits against short-circuit damage automatically.
Comes in TO-220 and compact SMD packages.
Applications
Used in analog systems requiring negative 15V rails.
Supports audio amplifiers with clean negative voltage supply.
Powers operational amplifiers in instrumentation applications.
Helps create dual voltage supplies with LM7815 regulator.
Useful in power supplies for measurement equipment.
Works in embedded designs with negative voltage requirements.
Fits industrial and lab-grade electronics needing −15V.
Specifications Table
| Parameter | Value |
|---|---|
| Output Voltage | −15V ± 2% |
| Maximum Output Current | 1A (with heatsink) |
| Input Voltage Range | −17V to −30V |
| Dropout Voltage | ~2V |
| Line Regulation | 10–50 mV |
| Load Regulation | 50–150 mV |
| Quiescent Current | 5–8 mA |
| Ripple Rejection | 60–80 dB |
| Operating Temperature Range | 0°C to +125°C |
| Junction Temperature Max | +150°C ‘ |
| Storage Temperature Range | −65°C to +150°C |
| Package Options | TO-220, DPAK, TO-92, SOT-223 |
