Texas Instruments TLC5925IDWR

Overview

TLC5925IDWR from Texas Instruments is a 16-channel constant-current LED sink driver IC used in LED display and lighting systems. It features 16 regulated current outputs (3–45 mA), ±4% channel-to-channel current accuracy, 30-MHz serial clock support, and operates from 3 V to 5.5 V supply. It drives LEDs with uniform brightness across varying forward voltages in signage and gaming machine displays.

For engineers reviewing the TLC5925IDWR datasheet, TLC5925IDWR pinout, TLC5925IDWR application, or TLC5925IDWR equivalent, key selection considerations include output current adjustability via R_EXT, thermal shutdown at 150–200°C, Schmitt-trigger input noise immunity, fast 100 ns OE response, and SOIC-24 package compatibility with high-density PCB layouts.

Technical Context

The TLC5925IDWR integrates a 16-bit serial-in/parallel-out shift register with independent output latches and 16 matched current-sink channels. Its internal current regulation uses an external R_EXT resistor to set all 16 outputs simultaneously, maintaining <±4% matching between channels and <±6% matching across devices.

It supports daisy-chain configuration via SDI/SDO, with LE controlling data latching and OE enabling/disabling all outputs synchronously. The device implements thermal shutdown protection and meets 1-kV HBM ESD rating, operating reliably from –40°C to +125°C ambient temperature.

Key Specifications

Pinout & Package

Package: SOIC-24 (DW), body size 15.40 mm × 7.50 mm, RoHS-compliant, moisture sensitivity level 1 (unlimited floor life).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED sink driver applications.

Compared with TLC5925IDWR, TLC5940IPWP adds grayscale control at higher complexity and cost, while STP16CP05MTR reduces feature set and protection for simpler, lower-risk applications - TLC5925IDWR balances programmability, protection, and ease of use in mid-tier LED systems.

Availability

TLC5925IDWR is available at Aetrix Electronics and suitable for LED display panels, gaming machine lighting, and white goods status indicators requiring stable component supply, long-term manufacturability, and automotive-grade temperature range support.

Supply support for TLC5925IDWR 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 company specializing in analog and embedded processing technologies, with leadership in power management, signal chain, and high-reliability interface solutions.

The TLC5925IDWR belongs to TI's LED driver product line, designed specifically for cost-effective, thermally robust constant-current sinking in industrial signage, entertainment equipment, and appliance displays.

FAQ

What is the maximum output voltage rating for the TLC5925IDWR?

The TLC5925IDWR supports up to 17 V at its OUT0–OUT15 pins. This allows driving strings of up to five standard white LEDs (VF ≈ 3.2 V each) in series without additional voltage translation. The 17-V rating is absolute maximum and applies across the full –40°C to +125°C operating temperature range. Exceeding this voltage risks permanent damage to the internal current-sink transistors.

How does the external R_EXT resistor set the output current in the TLC5925IDWR?

The TLC5925IDWR uses R_EXT connected between Pin 23 (R-EXT) and GND to establish all 16 output currents via I_OUT = (1.21 V / R_EXT) × 18. For example, 840 Ω yields ~26 mA per channel, and 1680 Ω yields ~13 mA. This scaling factor (×18) ensures tight matching - the same R_EXT value sets identical current across all channels and across multiple TLC5925IDWR devices on the same board.

Can the TLC5925IDWR be used in daisy-chain configuration, and how is it implemented?

Yes, the TLC5925IDWR supports daisy chaining via its SDI and SDO pins. Serial data enters the first device at SDI, shifts through its 16-bit register, and exits at SDO to feed the SDI of the next TLC5925IDWR. All devices share the same CLK, LE, and OE signals. This allows driving hundreds of LEDs with minimal MCU GPIO usage - for example, 10 TLC5925IDWR devices control 160 LEDs using only four control lines plus one data line.

What is the purpose of the OE (Output Enable) pin on the TLC5925IDWR, and what is its timing specification?

The OE pin (Pin 21) is an active-low global output enable that blanks all 16 current sinks simultaneously. When OE is high, outputs are disabled (high-impedance sink state); when OE is low, outputs reflect latch data. Its minimum pulse width is 300 ns at VDD = 3 V and 200 ns at VDD = 5.5 V, enabling precise frame-blanking for flicker-free PWM dimming. Internal pullup ensures safe default-off behavior at power-up.

Does the TLC5925IDWR include any built-in protection features, and how do they operate?

Yes, the TLC5925IDWR includes thermal shutdown protection that disables all outputs when junction temperature reaches 150–200°C, with 15°C hysteresis for automatic recovery. It also features 1-kV HBM ESD rating on all pins and Schmitt-trigger inputs for noise immunity. These protections are fully integrated - no external components are needed. The thermal shutdown threshold is factory-trimmed and specified across temperature, ensuring reliable operation in enclosed or high-ambient environments.