STMicroelectronics LF50CV

Overview

LF50CV from STMicroelectronics is a very low-dropout linear voltage regulator delivering 5.0 V ±1% (AB grade) output at up to 500 mA, featuring 0.45 V dropout at 200 mA, 50 µA quiescent current in OFF mode, and logic-controlled shutdown. It serves as a local power supply in automotive infotainment modules, body control units, and ADAS camera subsystems requiring stable 5 V rail under wide input (6–16 V) and extended temperature (−40 to 125 °C).

For engineers reviewing the LF50CV datasheet, LF50CV pinout, LF50CV application, or LF50CV equivalent, this page provides verified electrical specs, package mapping to DPAK/PPAK, thermal performance data, automotive-grade qualification status (AEC-Q100), and real-world use context for battery-sensitive and high-reliability embedded systems.

Technical Context

The LF50CV implements a PNP pass transistor architecture enabling ultra-low dropout and minimal quiescent current across load and temperature. Its internal current and thermal limiting protect against fault conditions without external circuitry.

It supports TTL-compatible logic shutdown (pin 2 in 5-pin PPAK) with VIL ≤ 0.8 V and VIH ≥ 2.0 V, enabling precise system-level power gating. Stability is achieved with only 2.2 µF output capacitance (ESR 0.1–10 Ω), reducing BOM count and PCB footprint.

Key Specifications

Pinout & Package

LF50CV is supplied in DPAK (TO-252) and PPAK (Power Package) variants. Both packages feature exposed thermal pad electrically connected to GND for enhanced heat dissipation. The 5-pin PPAK includes dedicated INH (inhibit) control on pin 2; the 3-pin DPAK omits this function and operates continuously enabled.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout automotive regulator applications.

Compared with TLV73350PDBVR and TPS7B6950QDCYRQ1, LF50CV uniquely combines AEC-Q100 qualification, 0.45 V dropout, and 2.2 µF stability in a single DPAK/PPAK solution - making it optimal for space-constrained, high-reliability 5 V automotive rails where input voltage margin is limited.

Availability

LF50CV is available at Aetrix Electronics and suitable for automotive infotainment systems, ADAS camera modules, and body control units requiring stable component supply across extended temperature and long lifecycle commitments.

Supply support for LF50CV 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 microcontrollers, power management ICs, and automotive-grade analog devices.

The LFXX series was developed specifically for automotive power management, targeting low-noise, low-quiescent-current local regulation in engine bay, cabin, and ADAS applications with stringent AEC-Q100 compliance.

FAQ

What is the minimum input voltage required for LF50CV to maintain regulation at full 500 mA load?

The LF50CV maintains 5.0 V output down to an input voltage of 5.45 V at 500 mA load, based on its maximum dropout voltage of 0.45 V. This allows reliable operation during automotive cold-crank events where battery voltage may dip to 6.5 V, provided PCB layout minimizes trace resistance between input capacitor and VIN pin.

Does LF50CV require an input bypass capacitor, and if so, what value and type is recommended?

Yes - a minimum 0.1 µF X7R ceramic capacitor must be placed within 5 mm of the VIN and GND pins. This stabilizes the input impedance during fast load transients and prevents oscillation due to source inductance. Larger values (e.g., 1–10 µF) may be added in parallel for bulk filtering, but the 0.1 µF local cap is mandatory per datasheet Figure 3 test circuit.

Can LF50CV be used in a 3-pin DPAK configuration without shutdown functionality?

Yes - the 3-pin DPAK variant (e.g., LF50CV-DT) has identical electrical performance but omits the INH pin. It operates permanently enabled and is pin-compatible with legacy TO-252 LDO footprints. No external pull-up or pull-down is needed; the inhibit function is physically absent in this package option.

How does the thermal performance of LF50CV in PPAK compare to DPAK under 500 mA continuous load?

In PPAK, R_thJA is 100 °C/W (vs. 100 °C/W for DPAK), but R_thJC is 8 °C/W (vs. 8 °C/W), meaning both packages deliver identical junction-to-case thermal resistance. However, PPAK's dual-GND pins and larger thermal pad improve PCB heat spreading - resulting in ~5–8 °C lower junction temperature at 500 mA with identical 2-layer 1-in² copper pour, per ST's AN4402 thermal guidelines.