Overview
The LM7812CT/NOPB is a 3-terminal positive voltage regulator produced by Texas Instruments. It is part of the LM340 and LM7805 family of monolithic voltage regulators. This device is designed to provide a fixed output voltage of 12 volts and can deliver up to 1.5 amps of output current. The LM7812CT/NOPB is known for its robust features, including internal current-limiting, thermal shutdown, and safe-area compensation, making it essentially indestructible if adequate heat sinking is provided.
It is widely used in various applications requiring stable and regulated voltage, such as industrial power supplies, switched-mode power supply (SMPS) post-regulation, HVAC systems, and test and measurement equipment. The regulator is available in several package options, including the TO-220 package, which is space-efficient and easy to use.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Output Voltage | 11.5 - 12.5 | V |
| Output Current | Up to 1.5 | A |
| Line Regulation | 120 mV (max) | - |
| Load Regulation | 120 mV (max) | - |
| Quiescent Current | 8 mA (typ) | - |
| Dropout Voltage | 2 V (typ) | - |
| Operating Temperature Range | 0 to 125 | °C |
| Package Type | TO-220 (NDE) | - |
| Junction-to-Ambient Thermal Resistance | 23.9 °C/W | - |
Key Features
- Output Current up to 1.5 A
- Fixed Output Voltage of 12 V
- Output Voltage Tolerances of ±2% at TJ = 25°C
- Line Regulation of 0.01% / V at 1-A Load
- Load Regulation of 0.3% / A
- Internal Thermal Overload, Short-Circuit, and SOA Protection
- Available in Space-Saving SOT-223 Package (though LM7812CT/NOPB is in TO-220)
- No Output Capacitance Required for Stability
Applications
- Industrial Power Supplies
- Switched-Mode Power Supply (SMPS) Post-Regulation
- HVAC Systems
- Test and Measurement Equipment
- Brushed and Brushless DC Motor Drivers
- Solar Energy String Inverters
Q & A
- What is the output voltage of the LM7812CT/NOPB?
The output voltage of the LM7812CT/NOPB is 12 volts.
- What is the maximum output current of the LM7812CT/NOPB?
The maximum output current is up to 1.5 amps.
- What are the key protection features of the LM7812CT/NOPB?
The device features internal thermal overload, short-circuit, and safe-area compensation protection.
- What is the operating temperature range of the LM7812CT/NOPB?
The operating temperature range is from 0 to 125°C.
- Does the LM7812CT/NOPB require an output capacitor for stability?
No, the LM7812CT/NOPB does not require an output capacitor for stability, although it can improve transient response.
- What are the common applications of the LM7812CT/NOPB?
Common applications include industrial power supplies, SMPS post-regulation, HVAC systems, and test and measurement equipment.
- What package types are available for the LM7812 series?
The LM7812 series is available in several packages, including TO-220, SOT-223, and others, though the LM7812CT/NOPB specifically comes in the TO-220 package.
- How does the LM7812CT/NOPB handle thermal issues?
The device has internal thermal overload protection and can be used with heat sinks to reduce thermal resistance.
- What is the junction-to-ambient thermal resistance of the LM7812CT/NOPB in the TO-220 package?
The junction-to-ambient thermal resistance is 23.9 °C/W.
- Can the LM7812CT/NOPB be used for adjustable output voltages?
Yes, the LM7812CT/NOPB can be used with external components to obtain adjustable output voltages and currents.
