on October 16th 177

L7812CV Voltage Regulator Specifications and Uses

The L7812CV is a widely used voltage regulator that helps maintain stable power in electronic devices. In this article, you'll learn about its features, how it works, and its different uses in electronics. Whether you're working on a small project or something more advanced, this guide will walk you through the basics of the L7812CV and how it can benefit your setup.

Catalog

Overview of the L7812CV

The L7812CV is a three-terminal positive voltage regulator designed to provide stable power in electronic circuits. It helps ensure smooth voltage regulation directly on the circuit board, addressing potential distribution problems that can occur when regulating power from a single point. This component features internal protection mechanisms like current limiting and thermal shut-down, which contribute to its durability and reliable operation under various conditions. It can supply more than 1 amp of output current, provided that sufficient heat dissipation is in place. While the L7812CV is primarily used for fixed voltage regulation, it can also be combined with additional components to allow for adjustable voltage and current outputs, giving it flexibility in various applications.

L7812CV Pin Configuration

CAD Model of the L7812CV

Symbol L7812CV

L7812CV Footprint

3D Model

Key Features of the L7812CV

Output current up to 1.5 A

Output voltages of 5; 6; 8; 8.5; 9; 12; 15; 18; 24 V

Thermal overload protection

Short circuit protection

Output transition SOA protection

2 % output voltage tolerance (A version)

Guaranteed in extended temperature range (A version)

Technical Specifications of the L7812CV

The L7812CV from STMicroelectronics includes its technical specifications, features, and parameters, as well as a comparison with other components that have similar characteristics to the L7812CV.

Type	Parameter
Lifecycle Status	ACTIVE (Last Updated: 7 months ago)
Factory Lead Time	24 Weeks
Contact Plating	Tin
Mount	Through Hole
Mounting Type	Through Hole
Package / Case	TO-220-3
Number of Pins	3
Weight	2.299997g
Operating Temperature	0°C ~ 125°C
Packaging	Tube
Tolerance	5%
JESD-609 Code	e3
Part Status	Active
Moisture Sensitivity Level (MSL)	1 (Unlimited)
Number of Terminations	3
Terminal Position	SINGLE
Number of Functions	1
Base Part Number	L7812
Pin Count	3
Voltage - Input (Max)	35V
Output Voltage	12V
Output Type	Fixed
Max Output Current	1.5A
Output Configuration	Positive
Quiescent Current	8mA
Output Voltage 1	12V
Number of Regulators	1
Min Input Voltage	14V
Protection Features	Over Temperature, Short Circuit
Voltage Dropout (Max)	2V @ 1A Typ
PSRR	55dB (120Hz)
Dropout Voltage	2V
Dropout Voltage1-Nom	2V
Min Output Voltage	12V
Power Supply Rejection Ratio (PSRR)	55dB
Nominal Output Voltage	12V
Height	9.15mm
Length	10.4mm
Width	4.6mm
REACH SVHC	No SVHC
Radiation Hardening	No
RoHS Status	ROHS3 Compliant
Lead Free	Lead Free

Block Diagram of the L7812CV

Circuit Diagram of the L7812CV

Test Circuits for the L7812CV

DC Parameter

Load Regulation

Ripple Rejection

Alternative Options for the L7812CV

Part Number	Description	Manufacturer
MC7815ACTG	Linear Voltage Regulator, 1A, 5 to 24V, Positive Vout: 15.0V; TJ: 0°C to +125°C, TO-220, SINGLE GAUGE, 3-LEAD, 50-TUBE	ON Semiconductor
BA178M15CP	Fixed Positive Standard Regulator, 15V Bipolar, MSFM3, TO-220, 3 PIN	ROHM Semiconductor
MC7812AECTBU	12V FIXED POSITIVE REGULATOR, PSFM3, ROHS COMPLIANT, TO-220, 3 PIN	Rochester Electronics LLC
P1406-15-883B	Fixed Positive Standard Regulator, 15V MSFM3, TO-257, 3 PIN	TT Electronics Resistors
OM7812AIH	Fixed Positive Standard Regulator, 12V Bipolar, MSFM3, TO-257A, 3 PIN	Infineon Technologies AG
UPC7815AHF	Fixed Positive Standard Regulator, 15V Bipolar, MSFM3, ISOLATED, PLASTIC, TO-220, SIP-3	NEC Electronics America Inc
UPC7812AHF-AZ	UPC7812AHF-AZ	Renesas Electronics Corporation
P7815AG-883B	15V FIXED POSITIVE REGULATOR, MSFM3, TO-257A, 3 PIN	TT Electronics Power and Hybrid / Semelab Limited
P7815AG-BS2S	Fixed Positive Standard Regulator, 15V MSFM3, TO-257A, 3 PIN	TT Electronics Resistors
SHD5158B	Fixed Positive Standard Regulator, 15V, SHD-5B, 3 PIN	Sensitron Semiconductors

L7812CV Applications

Constant +12V output regulator to power microcontrollers and sensors in most of the projects

Adjustable Output Regulator

Current Limiter for certain applications

Regulated Dual Supply

Output Polarity-Reversal-Protection Circuit

Example Application Circuit

Fixed Output Regulator

Package Details of the L7812CV

L7812CV Package Outline

L7812CV Mechanical Data

Dim.	Min. (mm)
A	4.4
b	0.61
b1	1.14
c	0.48
D	15.25
E	10
e	2.4
e1	4.95
F	0.51
H1	6.2
J1	2.4
L	13
L1	3.5
L20	-
L30	-
ØP	3.75
Q	2.65

L7812CV Tube

About the Manufacturer: STMicroelectronics

STMicroelectronics is a global leader in the semiconductor industry, known for producing a wide array of electronic components and solutions. They bring together expertise in silicon technology and system design, along with advanced manufacturing capabilities, which enables them to deliver innovative products that meet the needs of modern electronics. Their work spans across numerous applications, including microelectronics, and they are recognized for their ability to adapt to the fast-changing tech landscape. Through strategic collaborations and a strong intellectual property portfolio, STMicroelectronics continues to shape the future of electronics, helping devices become more efficient, connected, and user-friendly. Their products play a central role in enabling the convergence of technology, making it easier for various systems to work together in everyday applications.

Datasheet PDF

L7812CV Datasheets:

L7812CV.pdf

MC7815ACTG Datasheets:

MC7815ACTG.pdf

MC7815ACTG.pdf

Frequently Asked Questions [FAQ]

1. What is L7812CV?

The L7812CV is a three-terminal positive voltage regulator. It helps provide stable voltage regulation directly on the circuit board, which eliminates the challenges of managing voltage from a single point. It includes built-in features like current limiting and thermal shut-down, which makes it very durable and able to handle various conditions.

2. What is the difference between a fixed voltage regulator and an adjustable regulator?

A fixed voltage regulator requires almost no external components, aside from possibly a few bypass capacitors, to operate. On the other hand, an adjustable voltage regulator needs a few external components for proper functioning. With the adjustable type, you can have a wider range of voltage and current options, offering more flexibility for different needs.

3. Will an L78S12CV run cooler than an L7812CV under the same load?

Both the L78S12CV and the L7812CV have similar performance in terms of output voltage versus junction temperature. However, the operating temperature range is slightly different: the L7812CV works between 0°C and 125°C, while the L78S12CV can go up to 150°C. Despite this, both chips have the same thermal resistance, meaning the L78S12CV won’t necessarily run cooler under the same load, but it can handle higher temperatures if needed.

4. I'm using a L7812CV as a power adapter for a heating element made of nichrome wire, but the regulator heats up quickly. What could be wrong?

Nichrome wire creates a resistive load. Likely, your wire has a very low resistance, possibly under 100 ohms or even 1 ohm. When the resistance is this low, it can draw high current through the regulator. If you're feeding 17V into the regulator and getting 12V out, the 5V difference is being dissipated as heat. For every amp of current, that 5V drop results in 5 watts of heat. Since nichrome wire can draw a lot of current, your regulator is likely releasing a lot of heat.

5. How do you wire the L7812CV regulator IC?

If you’re using the TO-220 package, the easiest way to identify the pins is to look at the side with the labeling and point the pins downward. From left to right, pin 1 is the input, pin 2 is the ground, and pin 3 is the output. Make sure you provide a DC input because if you reverse the input and output, the chip can burn out. Also, ensure that the input voltage is not too high for the chip to handle.

6. What is the output voltage of the L7812CV regulator IC?

The L7812CV is a fixed voltage regulator that provides a stable 12V output. It can handle up to 1A of current, and the input voltage can range from 14V to 35V.