STMicroelectronics LF120CV

Overview

LF120CV from STMicroelectronics is a very low dropout (LDO) linear voltage regulator delivering 500 mA output current with 0.45 V dropout at 200 mA, ±1% output voltage accuracy (12 V), and 50 µA quiescent current in shutdown mode. It features TTL-compatible logic-controlled electronic shutdown (pin 2), internal current/thermal protection, and stable operation with only 2.2 µF output capacitance - designed for local regulation in battery-powered systems requiring standby power reduction.

For engineers reviewing the LF120CV datasheet, LF120CV pinout, LF120CV application, or LF120CV equivalent, this device is selected for ultra-low-noise, low-quiescent-power local regulation in automotive body electronics, industrial sensor nodes, and portable medical devices where input-to-output headroom is constrained and system-level power sequencing matters.

Technical Context

The LF120CV implements a PNP-based pass transistor architecture enabling sub-0.5 V dropout while maintaining tight load/line regulation (≤10 mV) across –40°C to 125°C. Its shutdown control pin accepts TTL-level inputs (V_IL ≤ 0.8 V, V_IH ≥ 2 V) and draws only 10 µA control current, enabling direct interfacing with microcontroller GPIOs without level-shifting.

It achieves 80 dB supply voltage rejection at 120 Hz and maintains ≥60 dB up to 10 kHz, with 50 µV RMS output noise (10 Hz–100 kHz), making it suitable for powering analog front-ends and RF subsystems sensitive to supply ripple and noise.

Key Specifications

Pinout & Package

LF120CV is supplied in the PENTAWATT-5 (vertical mount, 5-pin) package with exposed thermal pad, optimized for high-power dissipation in compact layouts. Pin 1 = Input, Pin 2 = Shutdown (TTL-compatible), Pin 3 = Ground, Pin 4 = Output, Pin 5 = Bypass (for noise filtering).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with LD1086S12TR and TPS7A4701RGWR, LF120CV uniquely balances 500 mA capability, 0.45 V dropout, integrated TTL shutdown, and 2.2 µF stability in a cost-effective PENTAWATT package - making it optimal for mid-power automotive and industrial subsystems requiring simple, robust, and controllable local regulation.

Availability

LF120CV is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor nodes, portable medical monitors, and smart energy meters requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LF120CV 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, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for automotive, industrial, and consumer markets.

The LF00 series - including LF120CV - was developed specifically for low-noise, low-quiescent-power local regulation in battery-fed and thermally constrained systems, emphasizing dropout performance, shutdown integration, and ease of stabilization.

FAQ

What is the minimum input voltage required for LF120CV to maintain 12 V output at 500 mA?

The LF120CV requires a minimum input voltage of 12.45 V to sustain 12 V output at 500 mA, based on its maximum dropout voltage of 0.45 V at 200 mA and 0.7 V at 500 mA per datasheet Table 9. At full load, headroom increases slightly due to pass element characteristics, so 12.7 V is recommended for margin in production designs.

Can LF120CV be used without the bypass (BP) pin connection?

Yes - the BP pin is optional. Leaving it open or connecting a 10 nF ceramic capacitor improves high-frequency PSRR and reduces output noise above 1 MHz, but regulation remains stable and functional without it. The 2.2 µF output capacitor alone satisfies all stability requirements per the datasheet.

Does LF120CV require an input capacitor?

Yes - a 0.1 µF ceramic capacitor is specified at the input (CI) in all electrical characteristic test conditions. It reduces high-frequency noise from upstream sources and prevents oscillation during fast load transients; placement within 5 mm of pins 1 and 3 is critical for optimal performance.

Is LF120CV pin-compatible with other LF00-series variants like LF33CV or LF50CV?

No - LF120CV uses the 5-pin PENTAWATT package with dedicated SHDN and BP pins, while LF33CV/LF50CV in TO-220 or DPAK packages are 3-terminal (IN/GND/OUT) with no shutdown or bypass functionality. Electrical pin mapping and thermal pad configuration differ; direct substitution requires PCB redesign.