STMicroelectronics L7810CV

Overview

L7810CV from STMicroelectronics is a three-terminal positive fixed-voltage linear regulator delivering 10 V at up to 1.5 A output current, featuring thermal overload protection, short-circuit protection, and safe operating area (SOA) protection. It operates with input voltages up to 35 V (for VO = 10 V), maintains ±2 % output voltage tolerance over temperature, and is housed in a TO-220 package for high-power dissipation in industrial power supply rails and local on-card regulation.

For engineers reviewing the L7810CV datasheet, L7810CV pinout, L7810CV application, or L7810CV equivalent, this device is selected for stable 10 V DC rail generation where low-noise, robust fault protection, and compatibility with standard heat sink mounting are required - especially in embedded control, instrumentation, and legacy analog subsystems.

Technical Context

The L7810CV implements a monolithic bipolar linear regulator architecture with internal current limiting, thermal shutdown, and SOA protection circuitry. Its dropout voltage is fixed at 2 V at 1 A load and 25 °C junction temperature, enabling operation with modest input–output differential headroom.

It requires minimum 5 mA load current for regulation stability and uses external 0.33 µF input and 0.1 µF output ceramic capacitors per ST's recommended test circuits. Output voltage drift is –1.0 mV/°C, and supply voltage rejection reaches 57 dB at 120 Hz under typical conditions.

Key Specifications

Pinout & Package

Package: TO-220 (3-pin, vertical mounting, metal tab electrically connected to Pin 2). Designed for mechanical attachment to heatsinks via the exposed collector tab.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-voltage linear regulator applications.

Compared with LM7810CT and MC7810CD2TR4G, the L7810CV offers superior supply rejection (57 dB vs. ≤55 dB), tighter output tolerance (±2 % vs. ±2.5 % or ±3 %), and higher guaranteed output current (1.5 A vs. 1.0 A), making it optimal for noise-sensitive industrial and instrumentation applications demanding long-term stability.

Availability

L7810CV is available at Aetrix Electronics and suitable for industrial PLC power rails, analog instrumentation supplies, embedded control board regulation, and automotive aftermarket module designs requiring stable component supply with full traceability and long-lifecycle support.

Supply support for L7810CV includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, MCU, power, and sensing solutions for industrial, automotive, and consumer markets.

The L78 series belongs to ST's legacy linear regulator product line, engineered specifically for rugged, cost-effective, and maintenance-free local voltage regulation in harsh environments - emphasizing fault resilience over efficiency.

FAQ

What is the minimum input voltage required for stable 10 V output from the L7810CV?

The L7810CV requires a minimum input voltage of 12 V DC to maintain regulation, based on its 2 V dropout voltage at 1 A and recommended 0.5 V margin. At lighter loads (<100 mA), VI can be reduced to ~11.5 V, but design margin should retain ≥12.5 V to ensure stability across temperature and line variations.

Can the L7810CV be used without a heatsink?

Yes, but only at very low output currents (<300 mA) and ambient temperatures <40 °C, given its R_thJA of 50 °C/W. At 1 A load and 25 °C ambient, junction temperature rises ~50 °C above ambient - exceeding safe limits without heatsinking. ST recommends a minimum 10 cm² aluminum heatsink for continuous 1 A operation.

Does the L7810CV require input and output capacitors, and what values are recommended?

Yes: ST specifies a 0.33 µF ceramic capacitor on the input (within 5 cm of Pin 1) and a 0.1 µF ceramic capacitor on the output (within 5 cm of Pin 3) to ensure stability and transient response. Larger bulk electrolytics (e.g., 10–100 µF) may be added in parallel for ripple reduction, but the ceramics are mandatory for phase margin.

How does the L7810CV behave during short-circuit conditions?

Under sustained short-circuit, the L7810CV limits output current to ~0.35 A (typical for C-version), activates thermal shutdown at ~165 °C junction temperature, and cycles on/off until fault is removed. It does not latch off permanently and resumes normal regulation once cooled and fault cleared - verified per DS0422 Rev 38 electrical test conditions.