Texas Instruments LP2988ILDX-3.8/NOPB

Overview

LP2988ILDX-3.8/NOPB from Texas Instruments is a micropower, 200 mA ultra-low-dropout linear voltage regulator with programmable power-on reset delay and bypass pin for noise reduction. It delivers 3.8 V output at ±0.5% accuracy (A-grade), 180 mV dropout at 200 mA, <2 µA shutdown current, and operates across −40°C to +125°C. It serves as the primary low-noise supply for precision analog circuitry in portable instrumentation.

For engineers reviewing the LP2988ILDX-3.8/NOPB datasheet, LP2988ILDX-3.8/NOPB pinout, LP2988ILDX-3.8/NOPB application, or LP2988ILDX-3.8/NOPB equivalent, key selection criteria include its 20 µV(RMS) output noise (with 0.01 µF bypass capacitor), 1.23 V internal reference, 2.2 µA delay pin current source, and SOIC-8 package compatibility with thermal design constraints up to 160°C/W θ_J−A.

Technical Context

The LP2988ILDX-3.8/NOPB uses a vertically integrated PNP (VIP) pass transistor architecture enabling ultra-low dropout and low ground current across load range. Its error comparator monitors output via internal 1.23 V reference and resistive divider, asserting open-collector ERROR when output falls >5% below nominal.

Power-on reset delay is implemented by charging an external capacitor on the DELAY pin using a 2.2 µA current source; the ERROR pin transitions high once DELAY pin voltage reaches 1.23 V. The BYPASS pin connects to the bandgap reference node, allowing external 0.01 µF capacitor to suppress output noise without loading the reference.

Key Specifications

Pinout & Package

LP2988ILDX-3.8/NOPB is supplied in an 8-pin SOIC (D) surface-mount package with θ_J−A = 160°C/W, RoHS-compliant lead finish (CuSn), and moisture sensitivity level (MSL) 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP2988IMX-3.8/NOPB, LP2988ILDX-3.8/NOPB provides tape-and-reel delivery and MSL-1 compatibility for production scalability, while TLS850F3TAV50 trades noise performance for automotive robustness-neither matches the 20 µV(RMS) noise + 0.5% accuracy combination of LP2988ILDX-3.8/NOPB in industrial test equipment.

Availability

LP2988ILDX-3.8/NOPB is available at Aetrix Electronics and suitable for portable medical sensors, automotive cabin control units, and industrial IoT edge nodes requiring stable component supply with guaranteed long-term availability.

Supply support for LP2988ILDX-3.8/NOPB 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 leader specializing in analog, embedded processing, and digital signal technologies with over 50 years of power management innovation.

The LP2988 series belongs to TI's precision LDO portfolio designed specifically for noise-sensitive, battery-constrained applications demanding ultra-low dropout, programmable reset, and sub-µA shutdown current.

FAQ

What is the maximum input voltage rating for LP2988ILDX-3.8/NOPB?

The LP2988ILDX-3.8/NOPB has an absolute maximum input voltage of +16 V and an operating input range of 2.1 V to +16 V. Exceeding 16 V risks permanent damage. For dual-supply systems where output may exceed input, an external Schottky diode from INPUT to OUTPUT is mandatory to clamp reverse voltage to ≤0.3 V, per TI's application hints.

How does the BYPASS pin reduce output noise in LP2988ILDX-3.8/NOPB?

The BYPASS pin connects directly to the internal 1.23 V bandgap reference node. Adding a 0.01 µF NPO/COG ceramic capacitor here filters reference ripple, lowering output noise from ~100 µV(RMS) (LP2987) to 20 µV(RMS) in LP2988ILDX-3.8/NOPB. Capacitor leakage must be minimal-high-quality ceramics or film types are required to avoid output voltage drift.

Can LP2988ILDX-3.8/NOPB be used with ceramic output capacitors?

Yes, but only with a series 1 Ω resistor to ensure minimum ESR for stability. The LP2988ILDX-3.8/NOPB requires output capacitance ≥4.7 µF and specific ESR range depending on load current. Ceramic capacitors often have ESR too low (<50 mΩ), risking oscillation; adding 1 Ω restores stability while preserving fast transient response.

What is the function of the SENSE pin on LP2988ILDX-3.8/NOPB?

The SENSE pin provides remote voltage sensing capability. When connected directly to the load instead of the OUTPUT pin, it compensates for PCB trace IR drop, improving load regulation to ±0.1% over full current range. If unused, SENSE must be tied to OUTPUT; floating it causes regulation failure.

How is power-on reset delay programmed on LP2988ILDX-3.8/NOPB?

Delay is set by connecting an external capacitor (CDLY) between DELAY pin and ground. The internal 2.2 µA current source charges CDLY; ERROR goes high when DELAY pin voltage reaches 1.23 V. Delay time is calculated as TDELAY = 5.59×10⁵ × CDLY (e.g., 100 nF → ~56 ms). Maximum recommended CDLY is 1 µF.