Texas Instruments LP38500TS-ADJ/NOPB

Overview

LP38500TS-ADJ/NOPB from Texas Instruments is an adjustable 1.5-A ultra-low-dropout linear regulator with PMOS pass transistor, operating from 2.7 V to 5.5 V input and delivering 0.6 V to 5 V output. It features FlexCap compensation for stability with ceramic/tantalum/aluminum capacitors, 25-nA shutdown current, and ±1.5% V_ADJ accuracy (A grade) at 25°C - used in FPGA core power supplies and precision ASIC rails.

For engineers reviewing the LP38500TS-ADJ/NOPB datasheet, LP38500TS-ADJ/NOPB pinout, LP38500TS-ADJ/NOPB application, or LP38500TS-ADJ/NOPB equivalent, key selection criteria include dropout voltage at 1.5 A (275 mV typ), ground-pin current (2 mA typ at full load), thermal shutdown threshold (170°C), and compatibility with 10-µF input/output capacitors without ESR constraints.

Technical Context

The LP38500TS-ADJ/NOPB uses internal feed-forward architecture to accelerate load transient response - achieving ≤40 mV deviation during 0.1 A → 1.5 A step at 0.5 A/µs slew rate. Its unique compensation eliminates ESR dependency, enabling stable operation with any capacitor type including low-ESR ceramics.

It implements overtemperature protection with 170°C trip point and 10°C hysteresis, plus current limiting that ensures safe short-circuit operation. The device operates in normal mode with 2 mA typical GND current at 1.5-A load and enters 25-nA shutdown when disabled via external circuitry (note: EN pin absent - disable requires input control).

Key Specifications

Pinout & Package

LP38500TS-ADJ/NOPB uses the TO-263 (NDQ) 5-pin package (10.16 mm × 9.85 mm body), with exposed thermal pad (DAP) electrically connected to GND and requiring PCB copper area for thermal conduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and MCP1826T-ADJ/DC, LP38500TS-ADJ/NOPB uniquely balances 1.5-A delivery, ultra-low dropout, and universal capacitor compatibility - making it optimal for space-constrained, multi-rail embedded systems where layout flexibility and transient robustness are critical.

Availability

LP38500TS-ADJ/NOPB is available at Aetrix Electronics and suitable for FPGA core power supplies, DSP I/O regulation, and ASIC power in set-top boxes requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for LP38500TS-ADJ/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 power management ICs, with decades of LDO innovation and automotive-grade reliability validation.

The LP38500 series belongs to TI's FlexCap LDO family, engineered specifically for high-current, low-noise, capacitor-flexible regulation in space-constrained digital systems - targeting FPGA, DSP, and ASIC power domains where transient response and layout simplicity are paramount.

FAQ

What is the maximum output current supported by LP38500TS-ADJ/NOPB?

LP38500TS-ADJ/NOPB delivers a guaranteed 1.5-A DC output current across its full operating temperature range (−40°C to +125°C). This rating assumes proper PCB thermal design using the exposed DAP pad connected to a ≥4 cm² copper pour. Derating applies above 85°C ambient per the R_θJA = 33.3°C/W specification.

Does LP38500TS-ADJ/NOPB have an enable (EN) pin?

No, LP38500TS-ADJ/NOPB does not include an enable pin. It is a non-enable variant of the LP3850x family - unlike the LP38502-ADJ which features an EN pin. To disable LP38500TS-ADJ/NOPB, the input supply must be removed or actively controlled externally; shutdown current remains at 25 nA only when VIN is absent or below UVLO threshold.

What capacitor types are compatible with LP38500TS-ADJ/NOPB?

LP38500TS-ADJ/NOPB is FlexCap-stable with ceramic (X5R/X7R), tantalum, and aluminum electrolytic output capacitors - no ESR limits apply. Input and output require ≥10-µF capacitance each, placed within 1 cm of the device. Ceramic capacitors are preferred for transient response; avoid Z5U/Y5F dielectrics due to severe capacitance loss with voltage and temperature.

How is the output voltage set on LP38500TS-ADJ/NOPB?

Output voltage is set using a two-resistor divider between OUT, ADJ, and GND. With V_ADJ = 0.605 V (typ) and I_ADJ ≤ 750 nA, V_OUT = 0.605 × (1 + R1/R2) + I_ADJ × R1. R2 must be ≤10 kΩ for loop stability; common values are R2 = 1.2 kΩ and R1 = 1.8 kΩ for 1.8-V output. Layout must minimize trace impedance to ADJ pin.

What thermal considerations apply to LP38500TS-ADJ/NOPB in TO-263 package?

LP38500TS-ADJ/NOPB in NDQ (TO-263) package has R_θJA = 33.3°C/W on standard JEDEC High-K board. For 1.5-A load at 3.3-V input and 1.2-V output (3.15 W dissipation), junction temperature rise is ~105°C - requiring ambient ≤20°C for safe 125°C max TJ operation. Use of ≥4 cm² GND-connected copper under the DAP pad is mandatory for rated performance.