STMicroelectronics LE30CD

Overview

LE30CD from STMicroelectronics is a very low dropout linear voltage regulator delivering 3.0 V ±2% output at up to 100 mA, with 0.2 V typical dropout at full load, 50 µA quiescent current in OFF mode, and TTL-compatible inhibit control. It operates across –40 °C to 125 °C and requires only a 2.2 µF ceramic output capacitor for stability-ideal for space-constrained battery-powered sensor nodes and portable instrumentation.

For engineers reviewing the LE30CD datasheet, LE30CD pinout, LE30CD application, or LE30CD equivalent, this page provides verified electrical specifications, SO-8 and TO-92 package details, real-world use cases in low-power embedded systems, and validated alternative parts with precise functional differences.

Technical Context

The LE30CD implements a PNP pass transistor architecture enabling ultra-low dropout (0.2 V typ. at 100 mA), combined with an internal inhibit logic circuit referenced to ground that accepts TTL-level signals on the INH pin (Pin 5 in SO-8). Its thermal protection and current limiting are fully integrated, eliminating external components for safe operation under transient overload or short-circuit conditions.

Unlike standard L78Lxx regulators, the LE30CD supports active shutdown via the inhibit function-reducing total system quiescent current to 50 µA-while maintaining identical pinout compatibility in both SO-8 and TO-92 packages. The SO-8 variant uses internally bonded pins 2, 3, 6, and 7 to the die attach flag for enhanced thermal dissipation (R_thJA = 55 °C/W).

Key Specifications

Pinout & Package

LE30CD is available in two industry-standard packages: SO-8 (surface-mount, 150 mil width) and TO-92 (through-hole, 3-pin). The SO-8 variant includes an inhibit (INH) pin for logic-controlled shutdown; the TO-92 version operates continuously without inhibit capability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LDL113PU33R, LE30CD offers tighter output tolerance (±2% vs ±3%) and enable control but lower current drive; versus L78L33ACZ, it delivers 11× lower quiescent current and 0.3 V lower dropout-critical for energy harvesting and long-life battery systems.

Availability

LE30CD is available at Aetrix Electronics and suitable for wireless sensor nodes, automotive body electronics, portable medical instruments, and industrial PLC I/O modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LE30CD 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 analog chips for industrial, automotive, and consumer markets.

The LE series regulators were developed specifically for ultra-low-power, high-reliability embedded systems-emphasizing minimal dropout, micropower shutdown, and robust thermal performance in compact packages.

FAQ

What is the minimum input voltage required for LE30CD to regulate 3.0 V output?

The LE30CD requires input voltage ≥3.2 V to maintain regulation at 100 mA load, based on its 0.2 V typical dropout voltage. At lighter loads, dropout decreases further-e.g., 0.1 V at 10 mA-allowing operation down to 3.1 V input. Input must remain below 18 V absolute maximum rating.

Can LE30CD be used without the inhibit function in SO-8 package?

Yes. When the INH pin (Pin 5) is tied to V_IN or left floating (though grounding is recommended to prevent noise coupling), the device remains permanently enabled. In this configuration, it behaves identically to the TO-92 version-providing continuous 3.0 V output with no shutdown capability.

Is a bypass capacitor required on the input pin of LE30CD?

While not strictly mandatory for stability, a 0.1 µF ceramic capacitor placed close to the V_IN pin is specified in all test circuits and strongly recommended to suppress high-frequency noise and improve transient response-especially when fed from a switching regulator or long PCB traces.

How does thermal performance differ between SO-8 and TO-92 packages?

The SO-8 package achieves R_thJA = 55 °C/W with standard PCB copper, versus 200 °C/W for TO-92, due to internal bonding of pins 2/3/6/7 to the thermal flag. This allows SO-8 to dissipate ~3.6× more power before reaching thermal shutdown-enabling 100 mA operation at higher ambient temperatures.