Texas Instruments TPS71728DSETG4

Overview

TPS71728DSETG4 from Texas Instruments is a fixed-output, 2.8 V, 150-mA low-dropout linear regulator with ultra-high PSRR (70 dB at 1 kHz), 30 µV_RMS output noise (100 Hz–100 kHz), and 170 mV typical dropout at full load - designed for powering noise-sensitive analog and RF circuits in compact portable devices.

For engineers reviewing the TPS71728DSETG4 datasheet, TPS71728DSETG4 pinout, TPS71728DSETG4 application, or TPS71728DSETG4 equivalent, key selection criteria include its SC-70-5 package footprint, enable-controlled shutdown (VEN(low) ≤ 0.4 V), 45 µA ground current at light load, and stability with only 1 µF ceramic output capacitance.

Technical Context

The TPS71728DSETG4 uses a PMOS pass device and high-gain BiCMOS error amplifier to achieve fast transient response and maintain high PSRR even at low headroom (VIN – VOUT = 1 V). Its dedicated NR pin connects to a 0.01 µF capacitor to filter bandgap reference noise and reduce output spectral noise density by up to 7×.

It integrates undervoltage lockout (UVLO rising threshold 2.45 V), thermal shutdown (trip at 160°C, reset at 140°C), and internal current limiting (typ. 325 mA). The device operates across –40°C to 125°C junction temperature and achieves ±3% output accuracy over line, load, and temperature.

Key Specifications

Pinout & Package

TPS71728DSETG4 is packaged in a 5-pin SC-70 (DCK) package measuring 2.00 mm × 1.25 mm, optimized for space-constrained mobile PCB layouts. 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 TPS71728DSETG4, TPS7A0528DBVR trades 80 mV higher dropout for 20 µA lower ground current, while MCP1700T-2802E/MB sacrifices PSRR and noise performance for lower unit cost and smaller footprint - making TPS71728DSETG4 optimal for RF/analog signal integrity-critical designs.

Availability

TPS71728DSETG4 is available at Aetrix Electronics and suitable for camera sensor power, mobile handset RF subsystems, Bluetooth® audio SoCs, and industrial IoT sensor nodes requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TPS71728DSETG4 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 focused on power integrity and signal-chain performance.

The TPS717 family was engineered specifically for noise-sensitive, space-constrained portable electronics - delivering high PSRR, ultra-low noise, and minimal quiescent current in sub-2 mm² packages for camera modules, wireless handsets, and wearable sensors.

FAQ

What is the maximum input voltage rating for the TPS71728DSETG4?

The TPS71728DSETG4 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 UVLO circuit activates below 2.45 V, ensuring safe startup behavior. For sustained operation, VIN should remain within the recommended range to guarantee ±3% output accuracy and thermal safety.

Does the TPS71728DSETG4 require an external noise reduction capacitor?

Yes - the TPS71728DSETG4 includes an NR pin specifically for connecting a 0.01 µF ceramic capacitor to reduce output noise and improve PSRR above 10 kHz. Without it, output noise rises to ~95 × V_OUT µV_RMS; with CNR = 0.01 µF, noise drops to 12.5 × V_OUT µV_RMS (30 µV_RMS at 2.8 V). The quick-start circuit charges this capacitor in ~135 µs, enabling fast turn-on.

Can the TPS71728DSETG4 operate with zero load current?

Yes - the TPS71728DSETG4 is explicitly designed to remain stable with no output load. Its low-current mode circuit boosts loop gain under no-load conditions, preventing output voltage drift or oscillation. This eliminates the need for a minimum load resistor, simplifying design for intermittent-sampling applications like motion-triggered sensor nodes where the LDO may sit idle for extended periods.

What is the thermal shutdown behavior of the TPS71728DSETG4?

The TPS71728DSETG4 enters thermal shutdown at approximately 160°C junction temperature and resets when cooled to ~140°C. This hysteresis prevents rapid cycling near the trip point. During shutdown, the output is disabled and ground current drops to sub-µA levels. Continuous thermal cycling indicates insufficient PCB copper area or excessive power dissipation - design margin should keep T_J ≤ 125°C under worst-case load and ambient conditions.

Is the TPS71728DSETG4 pin-compatible with other TPS717xx variants?

Yes - all fixed-output TPS717xx SC-70-5 variants (e.g., TPS71718, TPS71733) share identical pinout, package dimensions, and functional pin assignments (IN, GND, EN, NR, OUT). This allows drop-in replacement across output voltages without layout changes, provided input voltage and load requirements remain compatible with the new variant's specifications.