Texas Instruments TLV1117-25IDCY

Overview

TLV1117-25IDCY from Texas Instruments is a fixed-output, 2.5 V, 800 mA low-dropout linear voltage regulator in a 4-pin SOT-223 (DCY) package. It operates from 3.9 V to 15 V input, delivers ±1.0% output accuracy at 25°C, features 0.8–1.2 V dropout at 800 mA, and integrates foldback current limiting and thermal shutdown. It powers microcontroller I/O rails in industrial control modules where stable, low-noise 2.5 V supply is required.

For engineers reviewing the TLV1117-25IDCY datasheet, TLV1117-25IDCY pinout, TLV1117-25IDCY application, or TLV1117-25IDCY equivalent, key selection factors include its 2.5 V fixed output, 800 mA load capability, 0.8 V typical dropout at full load, integrated UVLO (2.2–2.4 V rising threshold), and SOT-223 thermal performance (R_θJA = 95.4°C/W).

Technical Context

The TLV1117-25IDCY implements a CMOS-based LDO architecture with an internal 1.25 V bandgap reference and error amplifier driving a PMOS pass transistor. Its foldback current limit activates below 50% of nominal output (1.25 V), reducing short-circuit current to 150–350 mA while maintaining thermal shutdown at 180°C with 20°C hysteresis.

This device requires no minimum load for regulation and includes internal soft-start to suppress inrush current during startup. Its UVLO circuit ensures clean enable/disable behavior with 130 mV hysteresis, and its output pulldown (0.7–1.1 mA) actively discharges the rail when disabled.

Key Specifications

Pinout & Package

The TLV1117-25IDCY uses a 4-pin SOT-223 (DCY) package with exposed thermal pad. Pin 1 is ADJ/GND (ground for fixed-output variants), Pin 2 is OUTPUT (2.5 V regulated rail), Pin 3 is INPUT (3.9–15 V supply), and Pin 4 is OUTPUT (second VOUT connection for improved current sharing and thermal conduction).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV1117-25CDCY, TLV1117-25IDCY adds guaranteed operation down to –40°C and tighter long-term stability (0.3% vs unspecified). Versus TPS7A4700RGWR, it trades ultra-low noise for 4× higher output current and SOT-223 compatibility-making it optimal for cost-sensitive, thermally demanding 2.5 V system rails.

Availability

TLV1117-25IDCY is available at Aetrix Electronics and suitable for industrial PLCs, smart meters, HVAC controllers, and home theater audio systems requiring stable component supply with full industrial temperature support and long-term lifecycle assurance.

Supply support for TLV1117-25IDCY 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 industrial qualification.

The TLV1117 product line delivers cost-optimized, thermally robust linear regulators for industrial automation, energy metering, and building control systems-designed for reliability under continuous load and wide ambient temperature swings.

FAQ

What is the minimum input voltage required for TLV1117-25IDCY to maintain 2.5 V regulation?

The TLV1117-25IDCY requires a minimum input voltage of 3.9 V under full 800 mA load, based on its 1.2 V maximum dropout specification. At lighter loads, input can drop as low as 3.3 V (2.5 V + 0.8 V typical dropout) while maintaining regulation. Below 3.9 V, UVLO may disable the device if VIN falls below 1.9 V.

Does TLV1117-25IDCY require an external capacitor on the ADJ pin?

No-TLV1117-25IDCY is a fixed-output variant, so Pin 1 functions solely as GND and does not connect to an external resistor divider. The ADJ pin is internally tied off; no external components are needed on that terminal. Only input and output capacitors (≥10 µF each) are required for stability.

How does the foldback current limit in TLV1117-25IDCY protect the device during a short circuit?

During a short, TLV1117-25IDCY limits output current to 150–350 mA (ISC), significantly below its 800 mA rating. This foldback action reduces power dissipation [(VIN – 0 V) × ISC] versus constant-current limiting, preventing thermal runaway. Combined with 180°C thermal shutdown, it enables safe fault containment without external protection.

Can TLV1117-25IDCY be used in parallel to increase output current beyond 800 mA?

No-TLV1117-25IDCY lacks built-in current-sharing circuitry. Paralleling multiple units risks unequal current distribution due to output voltage tolerance (±1.0%), leading to thermal imbalance and premature failure. For >800 mA, select a single higher-current LDO or switcher solution instead.

What is the purpose of Pin 4 (second OUTPUT) on the TLV1117-25IDCY SOT-223 package?

Pin 4 provides a second dedicated VOUT connection to reduce effective bond wire and trace resistance between the die and PCB copper pour. This improves current handling, lowers thermal impedance, and enhances transient response-especially critical for high-current, low-dropout operation in compact industrial layouts.