Texas Instruments LP38502ATJ-ADJ/NOPB

Overview

LP38502ATJ-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 ENABLE pin control-designed for FPGA, DSP, and ASIC power supplies in printers, routers, and set-top boxes.

For engineers reviewing the LP38502ATJ-ADJ/NOPB datasheet, LP38502ATJ-ADJ/NOPB pinout, LP38502ATJ-ADJ/NOPB application, or LP38502ATJ-ADJ/NOPB equivalent, key selection criteria include dropout voltage at 1.5 A (275 mV typ), ±1.5% V_ADJ accuracy (A grade), thermal shutdown at 170°C, enable logic thresholds (VIH = 1.4 V, VIL = 0.65 V), and WSON-8 package compatibility with high-density PCB layouts.

Technical Context

The LP38502ATJ-ADJ/NOPB uses internal feed-forward architecture to accelerate load transient response-achieving ≤40 mV deviation during 0.1 A → 1.5 A step-and employs unique compensation that eliminates ESR dependency for output capacitor selection. Its CMOS-based PMOS pass element enables low quiescent current (2 mA GND current at full load) and ensures stable operation across −40°C to +125°C junction temperature.

Unlike fixed-output LDOs, this device relies on external resistor divider feedback via the ADJ pin (V_ADJ = 0.605 V typ) to set output voltage, with I_ADJ bias current ≤750 nA. The ENABLE pin provides active-high digital control with 1 nA high-state current and 0.1 µA low-state leakage, supporting precise power sequencing in multi-rail systems.

Key Specifications

Pinout & Package

LP38502ATJ-ADJ/NOPB is housed in an 8-pin WSON package (3.00 mm × 2.50 mm, 0.5-mm pitch) with exposed thermal pad (DAP) requiring PCB ground connection for thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and MCP1826T-ADJ/DC, LP38502ATJ-ADJ/NOPB uniquely balances 1.5-A output, ENABLE functionality, FlexCap stability with 10-µF caps, and 25-nA shutdown-making it optimal for compact, sequenced, high-current digital power rails where capacitor flexibility and low standby power are essential.

Availability

LP38502ATJ-ADJ/NOPB is available at Aetrix Electronics and suitable for FPGA core supplies, DSP power rails, and ASIC I/O regulation requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for LP38502ATJ-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 and embedded processing technologies, with decades of expertise in power management IC design and manufacturing.

The LP3850x series was developed specifically for high-current, low-dropout regulation in space-constrained digital systems-emphasizing capacitor flexibility, fast transient response, and robust protection for FPGA, ASIC, and DSP applications.

FAQ

What is the minimum output capacitor required for stable operation of LP38502ATJ-ADJ/NOPB?

The LP38502ATJ-ADJ/NOPB requires a minimum 10-µF output capacitor located within 1 cm of the device. Unlike conventional LDOs, it imposes no ESR restrictions-enabling use of ceramic, tantalum, or aluminum types. X5R/X7R dielectrics are recommended for ceramic capacitors to maintain capacitance across temperature and voltage.

Does LP38502ATJ-ADJ/NOPB support power sequencing via its ENABLE pin?

Yes, LP38502ATJ-ADJ/NOPB includes an active-high ENABLE pin (Pin 2) with VIH ≥ 1.4 V and VIL ≤ 0.65 V. Pulling EN low disables regulation and reduces ground current to 25 nA typical. This enables precise power-up/down sequencing in multi-rail systems without external MOSFETs or logic.

What is the typical dropout voltage of LP38502ATJ-ADJ/NOPB at full 1.5-A load?

The typical dropout voltage of LP38502ATJ-ADJ/NOPB is 275 mV at 1.5-A load and 25°C. At worst-case conditions (125°C junction, 1.5-A load), dropout rises to 375 mV. This low dropout enables efficient regulation from 3.3-V inputs down to 1.2-V outputs while minimizing thermal dissipation.

How does the FlexCap feature of LP38502ATJ-ADJ/NOPB simplify capacitor selection?

FlexCap eliminates ESR dependency by using internal compensation that maintains ≥40° phase margin regardless of output capacitor type or ESR value. This allows designers to freely select ceramic (low ESL), tantalum (high volumetric efficiency), or aluminum (cost-effective bulk) capacitors-reducing qualification effort and enabling last-minute BOM changes.

What thermal considerations apply to LP38502ATJ-ADJ/NOPB in the WSON-8 package?

LP38502ATJ-ADJ/NOPB in WSON-8 has R_θJA = 52.5°C/W (with thermal vias under DAP). To sustain 1.5-A output at ambient temperatures up to 85°C, the DAP must be soldered to a ≥100-mm² copper pour connected to GND. Thermal shutdown activates at 170°C with 10°C hysteresis, protecting against sustained overload.

Can LP38502ATJ-ADJ/NOPB be used with an output voltage below 1.0 V?

Yes, LP38502ATJ-ADJ/NOPB supports output voltages as low as 0.6 V using the ADJ pin and external resistor divider. With V_ADJ = 0.605 V typ and I_ADJ ≤ 750 nA, setting R2 ≤ 10 kΩ ensures loop stability. For 0.8-V output, R1 ≈ 3.2 kΩ and R2 = 10 kΩ yields accurate regulation per the formula V_OUT = V_ADJ(1 + R1/R2) + I_ADJR1.