Texas Instruments TPS77618D

Overview

TPS77618D from Texas Instruments is a 500mA, 1.8V fixed-output low-dropout (LDO) voltage regulator in an 8-pin SOIC package, featuring 169mV typical dropout at 500mA, 2% output voltage tolerance over line/load/temperature, and open-drain power-good (PG) output for system monitoring. It delivers stable core voltage to DSPs and FPGAs in battery-powered embedded systems.

For engineers reviewing the TPS77618D datasheet, TPS77618D pinout, TPS77618D application, or TPS77618D equivalent, key selection criteria include PG assertion threshold (92–98% VOUT), ultralow 85µA quiescent current, thermal shutdown protection, and compatibility with 10µF low-ESR output capacitors.

Technical Context

The TPS77618D uses a PMOS pass element enabling dropout voltage directly proportional to load current and quiescent current independent of output loading-85µA typical from 0mA to 500mA. Its internal 1.183V reference and feedback loop ensure tight regulation across –40°C to +125°C.

It integrates an active-high open-drain PG output with 200ms delay, triggered when VOUT falls below 92–98% of nominal (1.656–1.764V), plus enable input with TTL-compatible thresholds (VEN(HI) ≥ 1.7V, VEN(LO) ≤ 0.9V) and thermal shutdown at 150°C.

Key Specifications

Pinout & Package

TPS77618D is housed in an 8-pin SOIC (D) package with exposed pad not connected internally; GND pins (1, 2, 3) provide low-impedance return paths, and IN/OUT pins are duplicated for current sharing and reduced trace resistance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS77618D, TPS79618DR offers higher current and lower IQ but demands different board layout and capacitor selection, while MCP1826T-1802E/DB reduces cost and complexity at the expense of integrated power monitoring and efficiency.

Availability

TPS77618D is available at Aetrix Electronics and suitable for FPGA core power, DSP I/O supply, and battery-powered sensor node applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TPS77618D 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 heritage and broad industrial qualification.

The TPS776xx family was engineered for high-reliability, low-power embedded systems requiring precise voltage regulation, integrated power monitoring, and robust thermal performance in space-constrained SOIC layouts.

FAQ

What is the minimum input voltage required for TPS77618D to regulate 1.8V output?

The minimum input voltage is determined by dropout: VIN(MIN) = VOUT + VDO. At 500mA, typical VDO is 169mV, so VIN must be ≥1.969V. Per datasheet, absolute minimum VIN is 2.7V unless VDO condition governs - thus 1.969V is valid for this load. The TPS77618D will maintain regulation down to this level, provided thermal limits are observed and COUT meets ESR requirements.

Does TPS77618D require a minimum load current to maintain regulation?

No. The TPS77618D is stable at zero load - no minimum load current is required. This is enabled by its PMOS pass architecture and internal compensation, which remain stable even with no output current. Applications such as standby modes or intermittent sensors benefit directly from this feature without needing dummy loads.

How is the power-good (PG) output of TPS77618D configured and used?

The PG pin is an open-drain output requiring an external pull-up resistor (typically 10–100kΩ to VIN or VCC). It asserts high when VOUT is ≥92% of 1.8V (≥1.656V) and goes low when VOUT drops below that threshold. The TPS77618D includes 200ms internal delay to prevent chatter during startup or brief transients, making it suitable for reliable power-on reset generation.

Can TPS77618D be used with ceramic output capacitors?

Yes - the TPS77618D is explicitly designed for stability with 10µF ceramic capacitors having ESR between 50mΩ and 1.5Ω. Unlike older LDOs, it does not require high-ESR tantalum or aluminum electrolytics. Multilayer ceramic capacitors (MLCCs) are recommended for their small size, low ESR, and reliability in automotive and industrial environments.

What thermal considerations apply to TPS77618D in SOIC-8 package?

In SOIC-8 (D) package, the TPS77618D has θJA = 250°C/W (no airflow). At 500mA with VIN = 3.3V, power dissipation is (3.3V − 1.8V) × 0.5A = 0.75W, raising junction temperature by 187.5°C above ambient - exceeding safe limits. Therefore, PCB copper area (GND pins 1–3 tied to solid plane) and moderate airflow are essential. Derating is required above +25°C ambient per the dissipation table.