Texas Instruments TPS76818QD

Overview

TPS76818QD from Texas Instruments is a 1.8-V fixed-output, 1-A low-dropout (LDO) voltage regulator in an SOIC-8 package, featuring PMOS pass element, 230 mV typical dropout at 1 A, ±2% output accuracy over temperature and load, and ultralow 85 µA quiescent current. It delivers stable power to microcontrollers, FPGAs, and DSPs in battery-powered industrial and automotive systems.

For engineers reviewing the TPS76818QD datasheet, TPS76818QD pinout, TPS76818QD application, or TPS76818QD equivalent, key selection criteria include dropout voltage at full load, power-good assertion threshold (92–98% VO), thermal shutdown behavior (150°C trip), EN logic compatibility (TTL), and stability with 10 µF/60 mΩ–1.5 Ω output capacitors.

Technical Context

The TPS76818QD uses a voltage-driven PMOS pass transistor-enabling constant 85 µA quiescent current across 0–1 A load and eliminating PNP saturation issues during dropout. Its internal 1.1834 V reference feeds a high-impedance feedback amplifier for precise regulation.

Power-good (PG) is an open-drain output asserting high when VO ≥92% of nominal and deasserting below 98%, with 0.5% hysteresis; EN enables shutdown mode (<1 µA standby current). The device requires no minimum load and remains stable with zero-load 10 µF ceramic or tantalum output capacitors.

Key Specifications

Pinout & Package

TPS76818QD is housed in an 8-pin SOIC (D) package with exposed pad thermal enhancement. Pin 1 is GND; pins 3 and 4 are parallel IN inputs; pins 5 and 6 are parallel OUT outputs; pin 8 is open-drain PG; pin 2 is EN; pin 7 is NC (no internal connection).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS76818QPWP, the TPS76818QD offers simpler layout and lower cost for moderate thermal loads; versus TPS7A4701RGWR, it trades higher noise and IQ for guaranteed 230-mV dropout and zero external components.

Availability

TPS76818QD is available at Aetrix Electronics and suitable for industrial control systems, automotive camera modules, and portable medical devices requiring stable component supply with long-term lifecycle support.

Supply support for TPS76818QD 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 designing analog ICs, embedded processors, and connectivity solutions for industrial, automotive, and consumer markets.

The TPS768xxQ family was engineered for high-reliability, low-quiescent-current LDO regulation in extended-temperature environments-targeting battery-powered instrumentation, automotive sensors, and mission-critical embedded controllers.

FAQ

What is the maximum input voltage for TPS76818QD?

The absolute maximum input voltage for TPS76818QD is 13.5 V, but the recommended operating range is 2.7 V to 10 V. Exceeding 10 V risks violating safe operating area limits, especially at high ambient temperatures. For 1.8-V output, minimum input is 2.7 V per datasheet specification-not VO + VDO-due to internal circuitry constraints.

Does TPS76818QD require an external resistor divider for output setting?

No, TPS76818QD is a fixed-output 1.8-V regulator; its FB/NC pin (pin 7) is internally connected to the feedback network and must be left unconnected. Only the adjustable TPS76801 variant requires external R1/R2 resistors; using them with TPS76818QD will cause regulation failure.

How does the power-good (PG) output behave during startup and dropout?

The PG output of TPS76818QD is open-drain and asserts high only when VO reaches ≥92% of 1.8 V (≥1.656 V) and remains high until VO falls below 98% (≤1.764 V), providing 0.5% hysteresis. It does not assert during initial power-up until regulation is achieved, and deasserts cleanly during brownout-enabling robust power sequencing without external timers.

Can TPS76818QD operate without an output capacitor?

No, TPS76818QD requires a minimum 10 µF output capacitor with ESR between 60 mΩ and 1.5 Ω for loop stability. Omitting it causes oscillation and output voltage collapse. Ceramic, tantalum, or aluminum electrolytic types are acceptable if ESR and capacitance meet spec-solid tantalum is preferred for reliability in automotive use.

What thermal derating applies to TPS76818QD in SOIC-8 package?

TPS76818QD in SOIC-8 (D) package has a junction-to-ambient thermal resistance (RθJA) of 172°C/W at zero airflow. At +70°C ambient, its maximum continuous power dissipation drops to 312.5 mW (derated from 568.18 mW at +25°C), limiting practical 1-A operation to VIN ≤3.4 V unless additional copper heatsinking is applied per TI's recommended layout.