Texas Instruments TLV77128PDQNR

Overview

TLV77128PDQNR from Texas Instruments is a 150mA, fixed 2.8V output low-dropout linear regulator in a 4-pin X2SON (DQN) package, featuring 55dB PSRR at 1MHz, 113mV dropout at 150mA, and ±2% output voltage accuracy over –40°C to +125°C. It delivers stable power to noise-sensitive analog and digital circuitry in space-constrained portable electronics.

For engineers reviewing the TLV77128PDQNR datasheet, TLV77128PDQNR pinout, TLV77128PDQNR application, or TLV77128PDQNR equivalent, key selection criteria include its high PSRR for RF/ADC supply filtering, active output pulldown for controlled shutdown, foldback current limiting for fault resilience, and compatibility with 0.47–40µF ceramic output capacitors without external compensation.

Technical Context

The TLV77128PDQNR employs a CMOS pass transistor architecture with internal soft-start and thermal shutdown (160°C trip, 140°C reset). Its enable input (VEN(HI) = 0.9V, VEN(LOW) = 0.3V) supports precise system-level power sequencing, while the active pulldown resistor (135Ω typical) ensures rapid output discharge during disable.

Stable operation requires only a 1µF input and ≥0.47µF ceramic output capacitor; ESR independence eliminates need for tantalum or polymer alternatives. Dropout voltage scales linearly with load current via R_DS(ON) ≈ 0.75Ω (calculated from 113mV/150mA), enabling predictable performance across input voltage range (1.4V–5.5V).

Key Specifications

Pinout & Package

TLV77128PDQNR uses a 1mm × 1mm, 4-pin X2SON (DQN) package with exposed thermal pad. The compact footprint enables placement in tight layouts (e.g., camera modules, wearables), and the thermal pad must be connected to GND for optimal junction-to-board thermal resistance (180.8°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV77128PDQNR, TPS7A0528PDBVR offers higher current but sacrifices PSRR and active discharge; TPL7407LPGEDR integrates switching functionality at the cost of LDO precision and flexibility - TLV77128PDQNR remains optimal for compact, noise-critical 2.8V analog rails.

Availability

TLV77128PDQNR is available at Aetrix Electronics and suitable for smartphone camera modules, industrial IoT sensor nodes, automotive infotainment displays, and gaming console audio subsystems requiring stable component supply with guaranteed long-term manufacturability.

Supply support for TLV77128PDQNR 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 connectivity technologies, with decades of LDO design expertise and broad automotive/industrial qualification.

The TLV771 product line delivers small-footprint, high-PSRR LDOs optimized for noise-sensitive portable and automotive applications where space, efficiency, and transient immunity are critical.

FAQ

What is the maximum input voltage rating for TLV77128PDQNR?

The absolute maximum input voltage for TLV77128PDQNR is 6.5V, but the recommended operating range is 1.4V to 5.5V. Exceeding 5.5V may trigger internal protection or degrade long-term reliability. Operation at 6.5V is strictly limited to transient conditions per datasheet Absolute Maximum Ratings and must not exceed 100ns duration.

Does TLV77128PDQNR require an input capacitor for stability?

No, TLV77128PDQNR does not require an input capacitor for stability, but a minimum 1µF ceramic capacitor is recommended between IN and GND to suppress source impedance effects and improve PSRR and transient response. This capacitor must be placed adjacent to the IN and GND pins to minimize parasitic inductance.

Can TLV77128PDQNR be used with output capacitance below 0.47µF?

No - TLV77128PDQNR requires a minimum effective output capacitance of 0.47µF for guaranteed stability. Derating due to temperature, bias, and tolerance means the nominal capacitor value must be ≥1µF (X7R/X5R) to ensure ≥0.47µF effective capacitance across operating conditions. Using smaller values risks oscillation or poor load transient response.

What is the purpose of the thermal pad on the TLV77128PDQNR DQN package?

The thermal pad on TLV77128PDQNR serves solely for heat dissipation - it must be soldered to a GND plane to achieve the specified R_θJB of 180.8°C/W. It is not electrically connected internally; connecting it to any potential other than GND violates the datasheet and risks device damage or thermal runaway.

How does the foldback current limit behave during a short-circuit event on TLV77128PDQNR?

During a short-circuit, TLV77128PDQNR initially limits current to ~420mA (brick-wall), then folds back to ~42mA as V_OUT drops below the foldback voltage (~1.4V). This reduces power dissipation [(VIN – VOUT) × I] and prevents thermal shutdown cycling. Recovery is automatic once the fault clears and V_IN remains above UVLO.