Texas Instruments TPS799185DDCR

Overview

TPS799185DDCR from Texas Instruments is a 200-mA, low-quiescent-current (40 μA), ultralow-noise (10.5 × V_OUT μV_RMS), high-PSRR (66 dB at 1 kHz) low-dropout linear regulator in a 5-pin SOT-23-THIN package, delivering a fixed 1.85 V output with 2% total accuracy over load, line, and temperature (–40°C to +125°C). It powers noise-sensitive RF blocks such as VCOs and WLAN front-ends.

For engineers reviewing the TPS799185DDCR datasheet, TPS799185DDCR pinout, TPS799185DDCR application, or TPS799185DDCR equivalent, key selection criteria include dropout voltage (100 mV at 200 mA), stability with ≥2-μF ceramic output capacitance, EN toggle inrush protection, NR pin for noise reduction, and thermal shutdown at 165°C.

Technical Context

The TPS799185DDCR uses a PMOS pass element with advanced BiCMOS process to achieve 100-mV dropout at 200 mA while maintaining high PSRR across 100 Hz–1 MHz. Its precision bandgap reference and high-gain error amplifier deliver 2% overall output accuracy and fast transient response.

It features an active pulldown circuit that engages on >5% output overshoot during enable, plus inrush current limiting activated immediately upon EN toggle. The NR pin bypasses internal bandgap noise, enabling <10.5 × 1.85 ≈ 19.4 μV_RMS output noise when paired with a 0.01-μF capacitor.

Key Specifications

Pinout & Package

TPS799185DDCR is housed in a 5-pin SOT-23-THIN package (2.90 mm × 1.60 mm, 0.9 mm height), optimized for space-constrained portable designs. Pin functions are validated per TI SBVS056L Rev L (Feb 2022).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS799185DBVR, the TPS799185DDCR offers identical regulation performance in a lower-profile package-critical for thin mobile devices-while the ADP125ARHZ-1.85-R7 trades noise/PSRR for broader input range and higher quiescent current, making it suitable only for less demanding analog or digital loads.

Availability

TPS799185DDCR is available at Aetrix Electronics and suitable for wireless LAN modules, wearable health monitors, and RF front-end power management requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS799185DDCR 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 for high-reliability applications.

The TPS799 family was engineered specifically for RF and precision analog systems needing ultralow noise, high PSRR, and minimal quiescent current-targeting VCOs, WLAN/BT radios, and portable medical sensors.

FAQ

What is the maximum input voltage rating for the TPS799185DDCR?

The TPS799185DDCR has an absolute maximum input voltage of 7.0 V. However, its recommended operating input range is 2.7 V to 6.5 V. Operation above 6.5 V risks exceeding safe junction temperature or violating absolute maximum ratings, even briefly. For reliable long-term use, VIN should remain within the recommended range, especially under full 200-mA load and high ambient temperatures.

Does the TPS799185DDCR require an input capacitor for stability?

No, the TPS799185DDCR does not require an input capacitor for stability, but TI recommends a 0.1-μF to 1-μF low-ESR ceramic capacitor near the IN pin to improve source impedance, transient response, and PSRR-especially when powered from noisy DC/DC converters or long PCB traces. This capacitor is optional but strongly advised for RF applications.

How does the NR pin function on the TPS799185DDCR?

The NR pin on the TPS799185DDCR connects to an external 0.01-μF capacitor to bypass noise from the internal bandgap reference. When used, this reduces integrated output noise from ~94 × V_OUT to 10.5 × V_OUT μV_RMS (≈19.4 μV_RMS). The NR pin is high-impedance, so low-leakage ceramic capacitors are required; the quick-start circuit fully charges CNR within ~135 μs at power-up.

What is the thermal shutdown behavior of the TPS799185DDCR?

The TPS799185DDCR activates thermal shutdown at 165°C junction temperature and resets automatically when TJ falls to 145°C. During shutdown, output is disabled and ground current drops to 150 nA. This hysteresis prevents oscillation near the trip point. The device's R_θJA is 225.3°C/W in the SOT-23-THIN package, so continuous 200-mA operation at high ambient requires careful PCB copper area design.

Can the TPS799185DDCR be used without connecting the EN pin?

Yes-the EN pin of the TPS799185DDCR can be left unconnected or tied directly to IN to enable permanent operation. When tied to IN, the device powers up whenever VIN is applied and remains active until VIN drops below UVLO threshold (1.9–2.65 V). No external pull-up is needed, simplifying designs where enable control is unnecessary.