Texas Instruments LP2983IM5-1.2

Overview

LP2983IM5-1.2 from Texas Instruments is a micropower 150-mA low-dropout linear voltage regulator in SOT-23-5 package, delivering a fixed 1.2 V output with ±1% accuracy (A-grade), 2.2 V to 16 V input range, and stable operation with zero-ESR ceramic output capacitors. It serves as a precision power supply for ultra-low-voltage digital cores in portable electronics.

For engineers reviewing the LP2983IM5-1.2 datasheet, LP2983IM5-1.2 pinout, LP2983IM5-1.2 application, or LP2983IM5-1.2 equivalent, key selection criteria include dropout behavior at 1.2 V output, ON/OFF control timing thresholds, ground current vs. load profile, and ESR pin configuration for ceramic capacitor stability.

Technical Context

The LP2983IM5-1.2 uses a vertically integrated PNP pass transistor architecture enabling sub-1% output tolerance and ultra-low ground current-75 µA at 1 mA load and 825 µA at 150 mA load. Its dedicated ESR pin (Pin 4) provides low-impedance return path for ceramic output capacitors, eliminating need for minimum ESR constraints.

It features active ON/OFF control with logic-compatible thresholds (ON ≥1.4 V, OFF ≤0.1 V at 25°C), thermal shutdown, foldback current limiting (400 mA short-circuit, 250 mA peak), and reverse-input protection requiring external Schottky diode if V_OUT > V_IN.

Key Specifications

Pinout & Package

SOT-23-5 (DBV) package: 2.90 mm × 1.60 mm body, 0.95 mm height, gull-wing leads. Thermal performance optimized via PCB copper spreading; R_θJA = 169°C/W on JEDEC High-K board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, low-ESR LDO applications.

Compared with LP2983IM5-1.2, the MCP1826T-1202E/DB offers higher output current but sacrifices accuracy and micropower efficiency, while the TPL7407LPGEDR integrates regulation into a driver IC - neither matches the LP2983IM5-1.2's combination of ±1% tolerance, zero-ESR ceramic support, and 75 µA quiescent current at light loads.

Availability

LP2983IM5-1.2 is available at Aetrix Electronics and suitable for cellular baseband power, wearable sensor nodes, industrial PLC I/O modules, and automotive infotainment core supplies requiring stable component supply, long-lifecycle availability, and guaranteed traceability.

Supply support for LP2983IM5-1.2 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

Texas Instruments is a global semiconductor company headquartered in Dallas, Texas, specializing in analog, embedded processing, and power management technologies with broad industrial, automotive, and consumer reach.

The LP2983 product line delivers micropower, high-accuracy LDOs optimized for ultra-low-voltage digital systems (≤1.2 V) using vertically integrated PNP processes - targeting battery-powered portable and space-constrained embedded applications.

FAQ

What is the minimum input voltage required for LP2983IM5-1.2 to regulate 1.2 V output?

The LP2983IM5-1.2 requires a minimum input voltage of 2.2 V to maintain regulation, with a recommended headroom of at least 1 V above V_OUT (i.e., ≥2.2 V). At 25°C, the absolute minimum VIN to sustain 1.2 V output under 150 mA load is 2.05 V, but 2.2 V is specified across the full −40°C to +125°C junction temperature range. Below this, dropout occurs and output voltage drops linearly with input.

How does the ESR pin (Pin 4) function in the LP2983IM5-1.2?

The ESR pin (Pin 4) on the LP2983IM5-1.2 provides a dedicated low-impedance return path for the output capacitor's negative terminal, enabling stable operation with ceramic capacitors down to 0 Ω ESR. The output capacitor must be connected between Pin 5 (OUT) and Pin 4 (ESR), not to GND - this configuration isolates high-frequency feedback from ground noise and ensures phase margin across all load conditions.

Can LP2983IM5-1.2 be used with a 1 µF output capacitor?

No - the LP2983IM5-1.2 requires a minimum 2.2 µF ceramic output capacitor connected between OUT and ESR pins for guaranteed stability across 0–150 mA load range. Using 1 µF violates the minimum capacitance requirement and risks oscillation, especially at elevated temperatures where ceramic capacitance degrades (e.g., Y5V/Z5U types drop >50%). X7R 2.2 µF is acceptable if rated for full temperature range.

What is the shutdown current of LP2983IM5-1.2 when the ON/OFF pin is pulled low?

When the ON/OFF pin of the LP2983IM5-1.2 is driven below 0.05 V over the full −40°C to +125°C temperature range, the device enters shutdown mode with ground current limited to ≤12 µA (typical 1 µA). This ultra-low shutdown current preserves battery energy in intermittently powered systems such as IoT edge sensors and remote metering devices.

Does LP2983IM5-1.2 require an external Schottky diode, and why?

Yes - an external Schottky diode (cathode to IN, anode to OUT) is required if the output voltage may ever exceed the input voltage (e.g., during power-down sequencing or backup battery switchover). The LP2983IM5-1.2's internal PNP pass transistor includes a parasitic diode from OUT to IN; reverse bias >0.3 V forward-biases it, risking SCR latch-up and permanent damage. The Schottky diode clamps reverse voltage to ~0.3 V, satisfying Absolute Maximum Ratings.