Texas Instruments LP38512TS-1.8/NOPB

Overview

LP38512TS-1.8/NOPB from Texas Instruments is a 1.5A fast-transient response low-dropout linear voltage regulator with fixed 1.8V output, ±2.5% DC accuracy over −40°C to +125°C, 2.25V–5.5V input range, and integrated error flag for digital core power monitoring in FPGAs and ASICs.

For engineers reviewing the LP38512TS-1.8/NOPB datasheet, LP38512TS-1.8/NOPB pinout, LP38512TS-1.8/NOPB application, or LP38512TS-1.8/NOPB equivalent, key selection criteria include dropout voltage (250 mV @ 1.5A), stability with 10 µF ceramic output capacitance, enable threshold hysteresis (200 mV), PSRR (40 dB @ 100 kHz), and thermal shutdown at 165°C.

Technical Context

The LP38512TS-1.8/NOPB employs a proprietary control loop architecture enabling sub-µs transient response to load steps from 10 mA to 1.5A, critical for powering high-speed digital cores. Its PMOS pass element delivers low dropout while supporting reverse-voltage protection via inherent parasitic diode conduction above 500 mV differential.

It integrates an open-drain ERROR flag with 74–93% falling/rising thresholds relative to nominal VOUT, hysteresis-enabled detection of >15% output sag, and active-low assertion during EN deactivation. Ground current remains ≤13 mA under full load, and quiescent current drops to 1 µA in shutdown.

Key Specifications

Pinout & Package

LP38512TS-1.8/NOPB uses the DDPAK/TO-263 (KTT) 5-pin surface-mount package with exposed thermal pad (DAP) electrically connected to GND (Pin 3) for enhanced heat dissipation. The DAP must be soldered to a PCB copper plane for thermal performance per θ_J-A = 60°C/W.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS74801DGNT and MCP1826-1802E/DB, the LP38512TS-1.8/NOPB uniquely combines integrated error flag, 40 dB PSRR at 100 kHz, and 250 mV dropout in a thermally optimized DDPAK package - making it optimal for space-constrained, fault-critical digital core supplies.

Availability

LP38512TS-1.8/NOPB is available at Aetrix Electronics and suitable for FPGA core power, DSP subsystem supply, DDR2 termination, server management controller rails, and high-reliability embedded computing requiring stable component supply and long-term manufacturability.

Supply support for LP38512TS-1.8/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 power management technologies, with decades of expertise in high-performance power regulation ICs.

The LP38512 series was designed specifically for fast-transient, high-accuracy digital core power in networking, telecom, and computing infrastructure - emphasizing low noise, small capacitor compatibility, and system-level fault awareness.

FAQ

What is the minimum input voltage required for LP38512TS-1.8/NOPB to regulate 1.8V at 1.5A?

The LP38512TS-1.8/NOPB requires a minimum input voltage of 2.05V to maintain regulation at 1.5A, calculated from its 250 mV typical dropout voltage plus 1.8V output. Its specified operating range starts at 2.25V to ensure margin across temperature, load, and process variation - confirming reliable startup and sustained regulation from 2.5V and 3.3V rails.

Can LP38512TS-1.8/NOPB operate without an external pull-up resistor on the ERROR pin?

No - the ERROR pin of LP38512TS-1.8/NOPB is an open-drain output and requires an external pull-up resistor (10 kΩ to 1 MΩ) to VIN to generate a valid logic-high signal. Without it, the ERROR pin remains floating and cannot indicate normal operation; TI explicitly states that pulling ERROR above VIN may cause unintended current flow through an internal parasitic diode.

Is LP38512TS-1.8/NOPB stable with less than 10 µF output capacitance?

No - LP38512TS-1.8/NOPB is characterized and guaranteed stable only with ≥10 µF ceramic output capacitance (X7R/X5R dielectric). Using smaller values risks oscillation or degraded transient response; Z5U/Y5V ceramics are discouraged due to severe capacitance loss under bias and temperature, which may compromise stability even at 10 µF nominal rating.

How does the EN pin behavior affect the ERROR flag on LP38512TS-1.8/NOPB?

When EN is pulled low, the LP38512TS-1.8/NOPB disables its control loop and forces the ERROR pin low immediately - independent of output voltage. This provides unambiguous system-level status: ERROR low means either output undervoltage OR regulator disabled. During normal operation (EN high), ERROR reflects true VOUT deviation with 74–93% hysteresis thresholds relative to 1.8V.

What thermal derating applies to LP38512TS-1.8/NOPB in a 2-layer PCB with 1 in² copper pour?

With 1 in² of 1-ounce copper connected to the DAP, LP38512TS-1.8/NOPB achieves θ_J-A ≈ 45°C/W. At 70°C ambient and 125°C max junction temperature, maximum allowable power dissipation is (125−70)/45 ≈ 1.22W. For 1.5A load at 2.5V input, power loss is (2.5−1.8)×1.5 + 2.5×0.013 ≈ 1.08W - within safe limit, but margin shrinks above 85°C ambient.