Voltage regulator 7905
🛠️ Voltage Regulator – 7905 (−5 V, 1 A)
Overview
The 7905 is a three-terminal negative linear voltage regulator that outputs a stable −5 V DC from a more negative input (typically −7 V to −35 V). It supports up to 1 A of output current and includes built-in protections like over-current, thermal shutdown, and safe-area limiting—making it dependable for use in dual-supply circuits, op‑amp rails, and audio preamps.
Key Features
Fixed −5 V DC output
Output current up to 1 A (1.5 A limited with thermal protection)
Input voltage range: typically between −7 V and −35 V
Protections: thermal shutdown, short-circuit, and safe-area limiting
Standard TO‑220 package
Low ground pin current allows for voltage boosting with resistors
Dropout voltage around 2 V
Pinout (Facing front with leads down)
Ground (GND) – reference point
Input (Vin) – more negative than −7 V
Output (Vout) – regulated −5 V
Applications
Dual power supplies (+5 V/−5 V) for analog circuits
Negative rail for op‑amps, DACs, and audio amplifiers
Negative sensor bias or reference supplies
Mixed-sign power rails in measurement systems
✅ Resources
📄 Datasheet: LM79XX Series −5 V Regulator – full specs, protections, and circuit examples gadgetronicx.com+15ti.com+15kynix.com+15youtube.com
🎥 YouTube Tutorial: “How to use a 7905 as a negative voltage source” – breadboard wiring, caps, and explanation infodatasheet.com+13youtube.com+13eleccircuit.com+13