Texas Instruments TPS71718DCKTG4

Overview

TPS71718DCKTG4 from Texas Instruments is a fixed-output, 1.8 V, 150-mA low-dropout linear regulator in SC-70-5 package, featuring ultra-high PSRR (70 dB at 1 kHz), low noise (30 µV_RMS, 100 Hz–100 kHz), and 170 mV typical dropout at full load - designed for powering noise-sensitive analog and RF circuits in portable wireless devices.

For engineers reviewing the TPS71718DCKTG4 datasheet, TPS71718DCKTG4 pinout, TPS71718DCKTG4 application, or TPS71718DCKTG4 equivalent, key selection considerations include its 45-µA quiescent current, 1-µF ceramic output capacitor stability, NR pin for noise reduction, thermal shutdown (160°C), and compatibility with 2.5 V to 6.5 V input rails in space-constrained layouts.

Technical Context

The TPS71718DCKTG4 uses a PMOS pass device and advanced BiCMOS process to achieve fast startup, excellent transient response, and high PSRR across wide frequency range - enabled by a precision band-gap reference and high-gain error amplifier. Its quick-start circuit charges the NR capacitor within ~160 µs for low-noise operation without sacrificing turn-on speed.

It operates over –40°C to +125°C junction temperature, supports zero-load stability via low-current mode circuitry, and integrates undervoltage lockout (UVLO rising threshold 2.45 V), overcurrent protection, and thermal shutdown with 20°C hysteresis - all while maintaining 3% worst-case output accuracy across line, load, and temperature.

Key Specifications

Pinout & Package

TPS71718DCKTG4 is packaged in a 5-pin SC-70 (DCK) package measuring 2.00 mm × 1.25 mm, optimized for ultra-compact PCB layouts in portable electronics. Thermal performance is characterized by R_θJA = 279.2°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise, low-I_Q LDO applications.

Compared with TPS71718DCKTG4, TPS71718DCKR offers identical performance in reel format for production, while MCP1700T-1802E/TT trades off PSRR and noise for lower I_Q - making TPS71718DCKTG4 the optimal choice for noise-critical 1.8-V analog/RF rails where 45-µA I_Q is acceptable.

Availability

TPS71718DCKTG4 is available at Aetrix Electronics and suitable for camera sensor power, mobile handset RF modules, and portable medical sensor nodes requiring stable component supply with traceable sourcing and long-term lifecycle support.

Supply support for TPS71718DCKTG4 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 LDO design expertise for high-reliability and high-performance applications.

The TPS717 family was engineered specifically for noise-sensitive, battery-powered portable electronics - delivering ultra-low noise, high PSRR, and micropower operation in sub-2-mm packages for space-constrained RF and imaging systems.

FAQ

What is the maximum input voltage rating for the TPS71718DCKTG4?

The TPS71718DCKTG4 has an absolute maximum input voltage of 7 V, but its recommended operating range is 2.5 V to 6.5 V. Exceeding 6.5 V may trigger internal protection or degrade reliability. The device's 170-mV dropout means it can deliver 1.8 V output from as low as 1.97 V input - however, minimum VIN is constrained to 2.5 V per datasheet specifications.

Does the TPS71718DCKTG4 require an external noise reduction capacitor?

Yes - the TPS71718DCKTG4 uses the NR pin to connect a 0.01 µF ceramic capacitor, which filters internal band-gap reference noise and achieves its specified 30 µV_RMS output noise. Omitting the NR capacitor increases output noise to ~95 × V_OUT µV_RMS (≈171 µV_RMS for 1.8 V), degrading performance in RF and precision analog applications.

Can the TPS71718DCKTG4 operate without any output load?

Yes - the TPS71718DCKTG4 remains stable and regulated at zero load due to its integrated low-current mode circuitry, which maintains loop gain under no-load conditions. This eliminates the need for minimum load resistors and supports intermittent-use applications like sensor wake-on-event systems where the output may be idle for extended periods.

What is the startup time of the TPS71718DCKTG4 with its recommended NR capacitor?

With a 0.01 µF NR capacitor, the TPS71718DCKTG4 achieves a typical startup time of 160 µs to reach 90% of 1.8 V output. This is enabled by an internal quick-start circuit that actively charges the NR capacitor. Startup time scales linearly with NR capacitance: t_START ≈ 160 µs + (540 × C_NR in nF) µs - so using 0.001 µF reduces startup to ~214 µs, while 0.1 µF extends it to ~700 µs.

How does the enable pin (EN) behave during power sequencing?

The EN pin of the TPS71718DCKTG4 is active-high with V_EN(high) ≥1.2 V (min) and V_EN(low) ≤0.4 V (max). It draws ≤1 µA and is TTL/CMOS-compatible. For controlled power sequencing, drive EN after VIN stabilizes; tying EN directly to VIN results in slower startup due to absence of quick-start activation until VIN exceeds UVLO threshold (~2.45 V).