Texas Instruments TPS799285DDCT

Overview

TPS799285DDCT from Texas Instruments is a 200-mA, fixed-output 2.85-V low-dropout linear regulator with enable (EN), ultralow noise (10.5 × V_OUT μV_RMS), high PSRR (66 dB at 1 kHz), and 40-μA quiescent current - designed for powering noise-sensitive RF and precision analog circuits in space-constrained portable systems.

For engineers reviewing the TPS799285DDCT datasheet, TPS799285DDCT pinout, TPS799285DDCT application, or TPS799285DDCT equivalent, this page delivers verified specifications, validated SOT-23-THIN pin mapping, confirmed 2% output accuracy over –40°C to +125°C, and real-world design implications of its 100-mV dropout at 200 mA and NR-capacitor–enabled noise reduction.

Technical Context

The TPS799285DDCT employs a PMOS pass element with an advanced BiCMOS process to achieve 100-mV typical dropout at full 200-mA load while maintaining stability with ≥2-μF ceramic output capacitance. Its high-gain error amplifier enables 66-dB PSRR at 1 kHz and fast transient response via active pulldown (350-Ω equivalent) on 5% output overshoot.

It integrates inrush current protection triggered by EN toggle start-up, undervoltage lockout (UVLO) with 70-mV hysteresis, thermal shutdown at 165°C, and a dedicated NR pin for external 0.01-μF bypass capacitor to suppress bandgap reference noise - reducing total output noise to 30.0 μV_RMS at V_OUT = 2.85 V.

Key Specifications

Pinout & Package

TPS799285DDCT is packaged in a 5-pin SOT-23-THIN (DDC) measuring 2.90 mm × 1.60 mm, optimized for high-density PCB layouts in handheld and wearable devices.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS799285DDCT, TPS799285DBVR offers identical regulation performance in a marginally thicker package, while ADP160ACBZ-2.85-R7 trades 66-dB PSRR and 30-μV_RMS noise for 1.5-μA quiescent current - making TPS799285DDCT the sole choice for RF-sensitive 2.85-V rails demanding simultaneous low noise, high PSRR, and compact size.

Availability

TPS799285DDCT is available at Aetrix Electronics and suitable for RF front-end power, wearable sensor hubs, EPOS display backlights, and VCO/PLL core supplies requiring stable component supply with guaranteed long-term sourcing.

Supply support for TPS799285DDCT 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 innovation focused on power integrity and signal-chain performance.

The TPS799 family was engineered specifically for noise-critical RF and precision analog applications - delivering ultralow noise, high PSRR, and micropower operation in miniature packages like SOT-23-THIN and DSBGA.

FAQ

What is the minimum input voltage required for TPS799285DDCT to regulate 2.85 V at 200 mA?

The minimum input voltage is determined by dropout: V_IN(MIN) = V_OUT + V_DO. At 200 mA and T_J = 25°C, V_DO = 100 mV typical, so V_IN(MIN) = 2.95 V. Per datasheet Section 6.3, absolute minimum VIN is 2.7 V - but below 2.95 V, output current must be reduced to maintain regulation. TPS799285DDCT cannot sustain 200 mA at 2.7 V input.

Can TPS799285DDCT operate without the NR capacitor, and what is the impact on noise?

Yes, TPS799285DDCT operates stably without the NR capacitor. However, output noise increases significantly: from 30.0 μV_RMS (with 0.01-μF CNR) to 94 × V_OUT = 268 μV_RMS (no CNR). This 9× degradation makes the NR pin essential for RF and precision analog applications. The NR pin is high-impedance; use low-leakage ceramic capacitors only.

Is TPS799285DDCT pin-compatible with other TPS799 fixed-voltage variants in SOT-23-THIN?

Yes - all TPS799 fixed-output versions (e.g., TPS799125DDCT, TPS79933DDCT) share identical 5-pin SOT-23-THIN (DDC) pinout: Pin 1=IN, Pin 2=GND, Pin 3=EN, Pin 4=NR, Pin 5=OUT. Only the output voltage differs; no PCB redesign is needed when swapping between fixed-voltage TPS799DDCT variants.

What thermal derating applies to TPS799285DDCT in the SOT-23-THIN package at 200 mA?

With θ_JA = 225.3°C/W and P_D = (V_IN – V_OUT) × I_OUT, at V_IN = 3.85 V and I_OUT = 200 mA, P_D = 200 mW → ΔT_J = 45°C. Starting from 25°C ambient, junction temperature reaches 70°C - well below the 125°C max rating. Full 200-mA operation is thermally viable up to ~80°C ambient with standard PCB copper.

Does TPS799285DDCT require a minimum load for regulation stability?

No - TPS799285DDCT is stable with zero output load. However, output voltage accuracy specification (±2%) requires ≥500 μA load per Section 6.5. Below 500 μA, especially near T_J = 125°C, V_OUT error may exceed ±2%. For precision applications, maintain ≥500 μA minimum load or verify accuracy empirically at light loads.