Texas Instruments TPS73733DCQRG4

Overview

TPS73733DCQRG4 from Texas Instruments is a 1A, 3.3V fixed-output low-dropout (LDO) regulator with NMOS pass transistor topology, reverse current protection, and ultra-low dropout voltage of 122mV typical at 1A (new silicon). It operates from 2.2V to 5.5V input, achieves ±1.5% overall accuracy over line/load/temperature, and stabilizes with only 1μF ceramic output capacitor. It serves as post-regulator for switching supplies in portable FPGA power rails.

For engineers reviewing the TPS73733DCQRG4 datasheet, TPS73733DCQRG4 pinout, TPS73733DCQRG4 application, or TPS73733DCQRG4 equivalent, key selection criteria include dropout performance under 1A load, shutdown current below 20nA, thermal shutdown at 160°C, and compatibility with minimal 1μF ceramic output capacitance in space-constrained battery-powered designs.

Technical Context

The TPS73733DCQRG4 uses an NMOS pass transistor in voltage-follower configuration, enabling reverse current blocking and insensitivity to output capacitor ESR. Its BiCMOS process delivers high precision while maintaining low ground pin current - 880µA at 1A load (new silicon) and <20nA in shutdown.

It integrates foldback current limiting (1.05–2.2A), thermal shutdown (160°C trip), and internal charge pump (4MHz) to drive the NMOS gate above VOUT. The fixed 3.3V output version lacks FB/NR pins; regulation relies on factory-trimmed internal reference (1.204V nominal).

Key Specifications

Pinout & Package

SOT-223-6 (DCQ) package: 6.5mm × 7.06mm body with exposed thermal pad connected to GND. Pin 1 = IN, Pin 2 = OUT, Pin 3 = GND, Pin 4 = NR/FB (NC for fixed 3.3V version), Pin 5 = EN, Pin 6 = GND (tab).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS73733DCQRG4, the TPS73733DCQ offers identical performance with legacy packaging, while TPS7A3701DRBR trades ultra-low dropout and 1μF stability for tighter accuracy - making TPS73733DCQRG4 optimal for space- and headroom-constrained portable systems.

Availability

TPS73733DCQRG4 is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, and FPGA point-of-load regulation requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for TPS73733DCQRG4 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 expertise and broad automotive/industrial qualification.

The TPS737 family was engineered for portable and battery-powered applications demanding ultra-low dropout, reverse current protection, and minimal external components - targeting DSP, FPGA, and microprocessor core/I/O rails.

FAQ

What is the dropout voltage specification for TPS73733DCQRG4 at full 1A load?

The TPS73733DCQRG4 has a typical dropout voltage of 122mV at 1A output current using new silicon revision. This value is measured under VOUT = 3.3V and represents the minimum headroom required between input and output for regulation. Maximum dropout is 250mV across temperature and process variation.

Does TPS73733DCQRG4 require a minimum output capacitance, and what type is supported?

Yes, TPS73733DCQRG4 requires a minimum 1μF ceramic output capacitor for stability. It is specifically designed to be stable with any ceramic capacitor ≥1μF and does not require ESR tuning - eliminating dependency on tantalum or aluminum electrolytic types and simplifying layout.

How does the enable (EN) pin function on TPS73733DCQRG4, and what is its shutdown current?

The EN pin on TPS73733DCQRG4 is active-high with TTL/CMOS-compatible thresholds: device enables when EN ≥1.7V and shuts down when EN ≤0.5V. In shutdown, TPS73733DCQRG4 draws less than 20nA typical ground pin current, making it suitable for ultra-low-power sleep modes in battery-operated systems.

Is reverse current protection inherent to TPS73733DCQRG4, and how is it implemented?

Yes, TPS73733DCQRG4 provides inherent reverse current protection due to its NMOS pass transistor topology. When input voltage falls below output voltage, the NMOS body diode remains reverse-biased, limiting reverse leakage to <0.1µA - eliminating need for external blocking diodes in backup-supply or hot-swap configurations.

What thermal protection features does TPS73733DCQRG4 include, and at what temperatures do they activate?

TPS73733DCQRG4 integrates thermal shutdown that activates at 160°C junction temperature and resets at 140°C. It also includes foldback current limiting to reduce fault current during output short-circuits, preventing thermal runaway. These protections operate independently of enable state and are fully specified across –40°C to +125°C junction range.