Texas Instruments LP38869MHE/NOPB

Overview

LP38869MHE/NOPB from Texas Instruments is a 1A, low-dropout linear regulator with dual-mode operation (preset 2.5V or adjustable 0.8V–5.0V), ±0.75% output voltage accuracy over temperature, 200 mV dropout at 1A load, and 50 dB PSRR at 100 kHz - designed for FPGA, DSP, and MCU core power rails requiring tight regulation and low noise.

For engineers reviewing the LP38869MHE/NOPB datasheet, LP38869MHE/NOPB pinout, LP38869MHE/NOPB application, or LP38869MHE/NOPB equivalent, key selection considerations include its FlexCap compensation (stable with 1 µF ceramic/tantalum/aluminum capacitors), adjustable soft-start via external capacitor, open-drain RST with 8% VOUT threshold and 3 ms delay, and thermal shutdown at 160°C.

Technical Context

The LP38869MHE/NOPB integrates a high-gain error amplifier driving a P-channel MOSFET pass transistor, enabling low quiescent current (≤0.7 mA at 1A) and stable operation without gate drive current. Its dual-mode SET pin comparator selects between internal 2.5V feedback (SET ≤87 mV) or external resistor-divider configuration (VREF = 800 mV).

Internal architecture includes fold-back current limiting (1.7A under undervoltage), soft-start controlled by 6.7 µA constant-current charge of an external SS capacitor, and an open-drain RST comparator monitoring VOUT against 736 mV threshold (92% of nominal). Thermal protection activates at TJ = 160°C with 15°C hysteresis.

Key Specifications

Pinout & Package

LP38869MHE/NOPB is housed in a thermally enhanced 16-pin HTSSOP package with exposed thermal pad (DAP) soldered to PCB ground plane for optimal thermal performance (θJA ≈ 40°C/W with 2-in² copper).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and MCP1826T-2502E/OT, LP38869MHE/NOPB uniquely balances ±0.75% accuracy, 50 dB PSRR, FlexCap compatibility, and integrated sequencing features (RST, soft-start, shutdown) in a thermally optimized HTSSOP package - making it optimal for FPGA/MCU systems demanding both precision and robustness.

Availability

LP38869MHE/NOPB is available at Aetrix Electronics and suitable for FPGA core power, SMPS post-regulation, and sequenced MCU supply applications requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for LP38869MHE/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 design expertise and broad automotive/industrial qualification.

The LP38869MHE/NOPB belongs to TI's FlexCap LDO family, engineered specifically for high-performance digital systems needing simplified capacitor selection, tight DC accuracy, and integrated power sequencing functions without external components.

FAQ

What is the minimum input voltage required for LP38869MHE/NOPB to regulate 2.5 V output?

The LP38869MHE/NOPB requires a minimum input voltage of 2.7 V to maintain regulation at 2.5 V output, as specified in its operating input range. Below this, UVLO activates at 2.27 V (typical), disabling regulation. Dropout voltage is not the limiting factor here - the absolute minimum VIN is defined by the device's operational specification, not just VDO.

Can LP38869MHE/NOPB operate with a 1 µF ceramic output capacitor in adjustable mode?

Yes, LP38869MHE/NOPB is explicitly characterized and guaranteed stable with ≥1 µF ceramic, tantalum, or aluminum output capacitors in both preset and adjustable modes. Its FlexCap compensation architecture eliminates ESR dependency, so capacitor type and value do not require recalculating compensation components - unlike conventional LDOs.

How does the RST pin behave during LP38869MHE/NOPB shutdown?

During shutdown (SHDN ≤0.58 V), the RST pin is actively pulled low and remains low regardless of VOUT level. It only transitions high after SHDN is asserted high *and* VOUT has risen to ≥92% of nominal for ≥3 ms - ensuring reliable power-on reset signaling even during brown-out or slow startup conditions.

What is the maximum recommended value for the SET pin resistor divider in LP38869MHE/NOPB adjustable mode?

In adjustable mode, R2 (to GND) should be ≤10 kΩ to ensure sufficient current (>10× SET pin bias current) and minimize error from the 2–300 nA SET pin leakage. For a 3.3 V output, R2 = 10 kΩ yields R1 = 31.25 kΩ using VOUT = 0.8 V × (1 + R1/R2); tighter resistor tolerances (<0.5%) are recommended to maintain ±0.75% overall accuracy.

Does LP38869MHE/NOPB require input capacitance, and what is the minimum value?

Yes, LP38869MHE/NOPB requires ≥1 µF input capacitance (CIN) placed close to the IN pins. The datasheet specifies a 1 µF MLCC as the minimum value to ensure stability, reduce input ripple, and support transient current demands - especially critical when used downstream of high-frequency switching regulators.