Voltage regulator 7812
🛠️ Voltage Regulator – 7812 (12V, 1A/1.5A)
Overview The 7812 is a three-terminal linear voltage regulator that outputs a stable +12V DC from a higher input voltage (typically 14.5–35V). It can provide up to 1A of current (some versions up to 1.5A with adequate heatsinking), with internal protections such as over-current limiting, thermal shutdown, and safe operating area protection. It is widely used for powering various electronic circuits and modules that require a precise 12V supply, commonly found in automotive electronics, industrial control systems, audio amplifiers, and general-purpose power supplies.
Key Features
Fixed output voltage: +12V DC
Maximum output current: 1A (some versions up to 1.5A with heatsink)
Input voltage range: ~14.5V to 35V (minimum 2.5V above output voltage for regulation, so at least 14.5V is recommended for stable operation)
Internal short-circuit and thermal overload protection
Low quiescent current (~4-8mA)
Standard TO-220 package; other variants may exist
Typical Wiring with Capacitors
Vin → 7812 IN
GND → 7812 GND
Vout → 7812 OUT (regulated 12V)
Place 0.33µF capacitor from IN to GND close to the regulator (for stability, especially if the regulator is far from the power supply filter).
Place 0.1µF capacitor from OUT to GND close to the regulator (to improve transient response and high-frequency noise filtering).
Heatsink recommended if outputting high current or using a high dropout voltage (large difference between Vin and Vout), as linear regulators dissipate excess power as heat.
Applications
Regulated 12V power for various electronic projects and modules (e.g., small motors, relays, automotive accessories)
Small linear power supplies
Powering 12V LED strips or arrays
Post-regulation after switching supplies
Educational electronics and prototype breadboard circuits
✅ Resources