Texas Instruments TPS79028DBVR

Overview

TPS79028DBVR from Texas Instruments is a 2.8-V, 50-mA ultralow-power, low-noise LDO voltage regulator with PMOS pass element, 60 mV typical dropout at 50 mA, 17 µA quiescent current, and 56 µV_RMS output noise (measured on TPS79030 variant under identical test conditions). It serves as a precision power supply for battery-operated microcontrollers in portable medical sensors.

For engineers reviewing the TPS79028DBVR datasheet, TPS79028DBVR pinout, TPS79028DBVR application, or TPS79028DBVR equivalent, key selection criteria include dropout voltage at full load, standby current during sleep mode, bypass-capacitor-dependent noise reduction, thermal shutdown threshold, and SOT-23-5 package compatibility with high-density PCB layouts.

Technical Context

The TPS79028DBVR uses a PMOS pass transistor instead of a conventional PNP, enabling dropout voltage directly proportional to load current (60 mV typ. at 50 mA) and stable 17 µA quiescent current across 0–50 mA output range. Its internal 150-kΩ resistor and external BYPASS capacitor form a low-pass filter that suppresses reference noise.

Enable logic operates with 0.9 V low-level and 1.7 V high-level thresholds; no hysteresis is included. Overcurrent protection limits output to ~350 mA, and thermal shutdown activates at ~165°C with automatic recovery below ~140°C.

Key Specifications

Pinout & Package

TPS79028DBVR is housed in a 5-pin SOT-23 (DBV) package, 2.9 mm × 1.6 mm × 1.1 mm, with gull-wing leads and JEDEC MO-178 compliance. Thermal resistance is R_θJA = 259°C/W (low-K board) or 180°C/W (high-K board).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS79028DBVR, TPS78028DRVR offers superior ultra-low-power performance at the expense of higher cost and larger size, while MCP1700T-2802E/TT provides higher current capacity and lower IQ but lacks the integrated bypass architecture essential for precision analog supply noise control.

Availability

TPS79028DBVR is available at Aetrix Electronics and suitable for wearable health monitors, industrial handheld scanners, and portable diagnostic devices requiring stable component supply with guaranteed long-term availability.

Supply support for TPS79028DBVR 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 company headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, and personal electronics markets.

The TPS790xx product line was designed specifically for battery-powered portable equipment requiring ultralow quiescent current, low output noise, and minimal board space - targeting medical sensors, wearables, and wireless edge nodes.

FAQ

What is the minimum input voltage required for stable operation of the TPS79028DBVR?

The TPS79028DBVR requires a minimum input voltage of 3.8 V under full 50-mA load, calculated as VO(typ) + VDO(max) = 2.8 V + 125 mV. At light loads, VI may drop to 2.7 V per datasheet note, but 3.8 V ensures regulation across temperature and load extremes. Input above 10 V violates absolute maximum ratings.

Does the TPS79028DBVR support reverse current protection?

Yes, the TPS79028DBVR incorporates a back-gate diode within its PMOS pass element that conducts reverse current from OUT to IN when VI falls below VO - such as during system power-down. This behavior is inherent and uncontrolled; external reverse-blocking circuitry is recommended if sustained reverse conduction must be prevented.

How does the BYPASS pin affect startup time in the TPS79028DBVR?

The BYPASS pin connects internally to the voltage reference through a 150-kΩ resistor, forming an RC time constant with the external capacitor. Larger bypass capacitance (e.g., 0.1 µF vs. 0.01 µF) slows startup due to increased charging time, delaying output regulation by milliseconds - critical in wake-from-sleep timing budgets. Startup delay scales linearly with C_BYPASS.

What output capacitor ESR range ensures stability for the TPS79028DBVR?

The TPS79028DBVR requires an output capacitor with ESR between 0.2 Ω and 10 Ω for guaranteed stability. Capacitors outside this range - especially low-ESR ceramics - risk oscillation unless compensated with a series resistor. Minimum capacitance is 4.7 µF; values up to 100 µF are acceptable and improve transient response.

Is the TPS79028DBVR pin-compatible with other members of the TPS790xx family?

Yes, all TPS790xx variants including TPS79028DBVR share identical 5-pin SOT-23 (DBV) packaging and pinout: Pin 1=IN, Pin 2=GND, Pin 3=EN, Pin 4=BYPASS, Pin 5=OUT. Voltage-specific variants (1.5 V, 1.8 V, etc.) are functionally and physically interchangeable in layout, enabling design reuse across output voltage requirements.