Texas Instruments TLC59281DBQR

Overview

TLC59281DBQR from Texas Instruments is a 16-channel constant-current LED sink driver in SSOP-24 package, delivering precise 35-mA per channel with ±1% channel-to-channel 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 video displays and message boards.

For engineers reviewing the TLC59281DBQR datasheet, TLC59281DBQR pinout, TLC59281DBQR application, or TLC59281DBQR equivalent, key selection criteria include constant-current sink capability, BLANK pulse width (20 ns), IREF resistor-based current setting, daisy-chain serial interface (SIN/SCLK/LAT/SOUT), and thermal performance in SSOP-24 at +85°C ambient.

Technical Context

The TLC59281DBQR implements a 16-bit serial shift register followed by a parallel latch to control on/off states of all 16 constant-current sinks independently. Its internal reference voltage (1.20 V typical) sets output current via external IREF resistor, with line regulation ±0.5%/V and load regulation ±1%/V.

It features CMOS-level logic inputs (VIH = 0.7×VCC, VIL = 0.3×VCC), 20-ns minimum BLANK pulse width for precise PWM dimming, and propagation delays under 30 ns (tD1/tD2) from LAT/BLANK edges to output current transition - critical for synchronized multi-device LED timing.

Key Specifications

Pinout & Package

Package: SSOP-24 (DBQ), 0.154-inch body width, exposed thermal pad (not internally connected to GND; must be externally tied to PCB ground).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC59282DBQR, the TLC59281DBQR lacks thermal shutdown but offers identical current accuracy and timing performance at lower cost; compared with MAX7219CWG+, it provides higher channel count and true constant-current sinking without multiplexing artifacts, making it suitable for high-fidelity video applications.

Availability

TLC59281DBQR is available at Aetrix Electronics and suitable for LED video displays, message boards, and architectural lighting requiring stable component supply, long-term production continuity, and RoHS-compliant packaging.

Supply support for TLC59281DBQR 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 power management technologies, with decades of experience in precision analog IC design.

The TLC59281 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 high-speed serial interface.

FAQ

What is the maximum LED supply voltage supported by the TLC59281DBQR?

The TLC59281DBQR supports an output voltage range of –0.3 V to +18 V on its OUT0–OUT15 pins, enabling direct connection to LED strings with forward voltages up to 17 V. This allows driving multiple high-Vf LEDs in series without external boost circuitry, provided the external LED power rail remains within the device's absolute maximum rating and thermal limits are observed.

How is the output current set on the TLC59281DBQR?

The TLC59281DBQR output current is set by an external resistor (RIREF) connected between the IREF pin and GND. With a typical internal reference voltage of 1.20 V, RIREF = 1.44 kΩ yields 35 mA per channel. The relationship follows IOUT = 42 × (1.20 V / RIREF), supporting 2–35 mA range. Values are confirmed in Table 1 of the SBVS139B datasheet.

Can multiple TLC59281DBQR devices be daisy-chained, and how does it work?

Yes - the TLC59281DBQR supports daisy-chaining via SIN and SOUT pins. Data shifted into SIN propagates through the internal 16-bit shift register; the MSB appears at SOUT on the next SCLK edge. By connecting SOUT of one device to SIN of the next, a single microcontroller can control dozens of TLC59281DBQRs with one serial stream and shared SCLK/LAT/BLANK lines.

What is the purpose of the BLANK pin on the TLC59281DBQR?

The BLANK pin on the TLC59281DBQR globally disables all 16 constant-current outputs when driven high, overriding the on/off latch state. It supports precise 20-ns minimum pulse widths for high-frequency PWM dimming and eliminates ghosting during data updates. During normal operation, BLANK is held low to allow individual channel control via the latch data.

Does the TLC59281DBQR require external decoupling capacitors, and where should they be placed?

Yes - the TLC59281DBQR requires a 0.1-µF ceramic decoupling capacitor placed as close as possible between VCC (pin 24) and GND (pin 1). Additional bulk capacitance (e.g., 4.7 µF tantalum) may be added nearby for systems with high peak current demands. Proper decoupling is essential to suppress supply noise induced by fast 10-ns output transients and prevent false triggering of logic inputs.