STMicroelectronics LE47ABZ

Overview

LE47ABZ from STMicroelectronics is a very low dropout (LDO) linear voltage regulator delivering 4.7 V ±1% output at up to 100 mA, with 0.2 V typical dropout at full load and 50 µA quiescent current in OFF mode. It features TTL-compatible inhibit control (pin 5 in SO-8), internal current/thermal limiting, and stable operation with only 2.2 µF output capacitance - making it ideal for space-constrained, battery-powered systems requiring precise local regulation and dynamic power gating.

For engineers reviewing the LE47ABZ datasheet, LE47ABZ pinout, LE47ABZ application, or LE47ABZ equivalent, key selection criteria include its 4.7 V fixed output accuracy, SO-8 package with integrated inhibit logic, -40 to 125 °C operating junction temperature range, and compatibility with low-ESR ceramic capacitors for minimal board area.

Technical Context

The LE47ABZ implements a PNP-based pass transistor architecture enabling ultra-low dropout voltage (0.2 V typ. at 100 mA), while its dedicated inhibit input allows external TTL-level control of regulator enable/disable state without requiring external pull-up or level-shifting circuitry. The device maintains tight output regulation (±1% at 25 °C) across line (3.4–18 V input), load (0.5–100 mA), and temperature (-40 to 125 °C) variations.

Its 80 dB supply voltage rejection at 120 Hz and 50 µV RMS output noise (10 Hz–100 kHz) support noise-sensitive analog and mixed-signal circuits. Thermal protection activates at junction temperatures exceeding 160 °C, and short-circuit current is internally limited to prevent damage during fault conditions.

Key Specifications

Pinout & Package

LE47ABZ is available in SO-8 package (modified frame with pins 2, 3, 6, 7 tied to die attach flag for enhanced thermal dissipation). Pin 5 is the TTL-compatible inhibit input; floating or high disables regulation (OFF mode), low enables output (ON mode).

Key Features

Applications

Equivalent & Alternatives

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

Compared with LDL1147PU33R and TLV70747PDQNR, LE47ABZ uniquely combines 100 mA capability, 0.2 V dropout, integrated inhibit logic, and SO-8 thermal robustness - making it optimal for thermally demanding, battery-gated applications where precision and control integration are essential.

Availability

LE47ABZ is available at Aetrix Electronics and suitable for battery-powered sensor nodes, automotive body control modules, industrial PLC I/O cards, and medical wearable front-ends requiring stable component supply with long-term manufacturability.

Supply support for LE47ABZ 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 specializing in power management, microcontrollers, and analog ICs for industrial, automotive, and consumer markets.

The LE series LDO regulators were designed specifically for low-power, high-accuracy local regulation in space- and energy-constrained systems - emphasizing ultra-low dropout, minimal quiescent current, and robust thermal performance in standard packages.

FAQ

What is the minimum input voltage required for LE47ABZ to maintain regulation at 100 mA load?

The LE47ABZ requires a minimum input voltage of 4.9 V to sustain 4.7 V output at 100 mA, based on its 0.2 V typical dropout voltage. At worst-case 0.5 V dropout (over temperature), input must be ≥5.2 V. Input voltage must remain below 18 V absolute maximum rating.

Can LE47ABZ be used without the inhibit function, and how should pin 5 be terminated?

Yes - pin 5 (INHIBIT) can be left unconnected or tied to V_IN to keep the regulator permanently enabled. However, STMicroelectronics recommends grounding pin 5 when inhibit is unused to prevent noise coupling and ensure deterministic ON-state behavior, as floating inputs may cause erratic output transitions.

What type and value of output capacitor is mandatory for stability with LE47ABZ?

A 2.2 µF ceramic capacitor with ESR between 0.1 Ω and 10 Ω is required for guaranteed stability. X7R or X5R dielectrics are preferred. Tantalum or aluminum electrolytic capacitors are not recommended due to higher ESR and aging effects that may compromise phase margin.

How does LE47ABZ handle thermal overload, and what is its safe operating area at 100 mA?

LE47ABZ includes internal thermal shutdown that activates above ~160 °C junction temperature. In SO-8 package with 2 oz copper heatsink, R_thJA is 55 °C/W - so at 100 mA and 5 V dropout (0.5 W dissipation), junction rise is ~27.5 °C above ambient, well within safe limits at ≤100 °C ambient. Derating is required above 100 °C ambient.