Texas Instruments TLC59281RGET

Overview

TLC59281RGET from Texas Instruments is a 16-channel constant-current LED sink driver in a 24-pin VQFN package, delivering up to 35 mA per channel with ±1% channel-to-channel current accuracy, 35-MHz serial data rate, and 10-ns switching transient time. It operates from 3.0 V to 5.5 V supply and supports LED power-supply voltages up to 17 V, enabling high-brightness, low-error LED video displays.

For engineers reviewing the TLC59281RGET datasheet, TLC59281RGET pinout, TLC59281RGET application, or TLC59281RGET equivalent, key selection criteria include constant-current sink capability, daisy-chainable serial interface (SIN/SCLK/LAT/BLANK), BLANK pulse width tolerance (20 ns), thermal pad grounding requirement, and IREF resistor-based current programming.

Technical Context

The TLC59281RGET integrates a 16-bit serial shift register and latch to control on/off states of all 16 constant-current sinks independently. Its internal reference voltage (1.20 V typical) at IREF sets output current via an external resistor, with line regulation of ±0.5%/V and load regulation of ±1%/V.

It features CMOS-level I/O compatibility, 20-ns minimum BLANK pulse width for precise PWM dimming, and propagation delays under 30 ns (LAT/BLANK to OUTn). The device supports daisy-chaining via SIN/SOUT, enabling scalable multi-driver systems without additional address decoding logic.

Key Specifications

Pinout & Package

Package: 24-pin VQFN (RGE), 4 mm × 4 mm, 0.5 mm pitch, with exposed thermal pad (pin 22) requiring PCB connection to GND for thermal management and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with TLC59282RGER, the TLC59281RGET omits diagnostic pins for lower cost and simpler layout; versus MAX7219CWG+, it delivers double the channel count, higher output voltage, and true daisy-chain scalability - making it optimal for large-area LED video and architectural lighting.

Availability

TLC59281RGET is available at Aetrix Electronics and suitable for LED video displays, message boards, and architectural illumination requiring stable component supply, RoHS-compliant packaging, and production-ready tape-and-reel delivery (250 units per reel).

Supply support for TLC59281RGET 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 high-reliability ICs, with decades of expertise in precision power and signal-chain solutions.

The TLC59281RGET belongs to TI's LED driver product line, engineered specifically for high-channel-count, constant-current LED control in commercial signage and video display systems demanding tight current matching and fast serial update rates.

FAQ

What is the maximum LED forward voltage supported by the TLC59281RGET?

The TLC59281RGET supports output voltages up to 17 V across its OUT0–OUT15 pins, allowing direct drive of multi-LED series strings (e.g., 5× white LEDs at 3.2 V each). This rating is absolute maximum; design margin should be applied based on ambient temperature and thermal management. The TLC59281RGET maintains constant-current regulation within this range when VCC is 3.0–5.5 V and IREF is properly configured.

How do I calculate the IREF resistor value for a target output current on the TLC59281RGET?

Use the formula RIREF = 42 × 1.20 V / IOLC, where IOLC is desired current in mA. For example, 35 mA requires RIREF ≈ 1.44 kΩ (42 × 1.20 / 35). The TLC59281RGET's internal 1.20 V reference ensures predictable current setting; resistor tolerance directly impacts accuracy. Standard 1% metal-film resistors are recommended for ≤±1% total error.

Can multiple TLC59281RGET devices be daisy-chained, and what is the timing constraint?

Yes - connect SOUT of one TLC59281RGET to SIN of the next, sharing common SCLK and LAT. Each device shifts in 16 bits, so N devices require 16×N SCLK cycles. TSU1 (100 ns setup from LAT↑ to SCLK↑) and TH1 (10 ns hold) must be met across the chain. The TLC59281RGET's 35-MHz SCLK supports >200 kHz update rates even for 10+ devices in series.

Is the thermal pad on the TLC59281RGET package electrically connected internally?

No - the exposed thermal pad (Pin 22) on the TLC59281RGET's VQFN package is not connected to any internal die node. It must be soldered to a PCB GND plane using ≥4 thermal vias for effective heat dissipation and EMI suppression. Failure to ground the pad may cause thermal shutdown or increased output current drift under load.

What happens to the outputs during power-up of the TLC59281RGET?

At power-up, the TLC59281RGET's on/off latch contains undefined data, so outputs may turn ON unpredictably if BLANK is low. TI recommends holding BLANK high until initialization completes. The TLC59281RGET requires explicit serial data write + LAT pulse to set known output states; no internal reset or default latch value is guaranteed. Always assert BLANK high at VCC ramp-up.