Texas Instruments TLC5926IDBQR

Overview

TLC5926IDBQR from Texas Instruments is a 16-channel constant-current LED sink driver IC designed for LED display and lighting systems. It delivers precise 5–120 mA per channel via external R-EXT resistor, supports 3.0–5.5 V logic supply, tolerates up to 17 V at output pins, and features open-load detection - used in outdoor LED signage panels requiring uniform brightness and fault monitoring.

For engineers reviewing the TLC5926IDBQR datasheet, TLC5926IDBQR pinout, TLC5926IDBQR application, or TLC5926IDBQR equivalent, this page provides verified functional mode timing, error detection behavior, current accuracy specs, thermal shutdown thresholds, and real-world implementation guidance for LED matrix control and fault-resilient lighting designs.

Technical Context

The TLC5926IDBQR integrates a 16-bit shift register and parallel output latches to convert serial data (SDI) into synchronized 16-channel sink outputs (OUT0–OUT15). Its constant-current regulation remains stable across load voltage changes (±0.1%/V), with Schmitt-trigger inputs ensuring noise immunity on CLK, LE(ED1), and OE(ED2).

It operates in two distinct modes: Normal Mode for LED driving and Special Mode for error status readback or 256-step global current gain adjustment. Open-load detection is active only when a channel is enabled, comparing actual output current against 0.5% of target current to flag open-circuit conditions.

Key Specifications

Pinout & Package

Package: SSOP-24 (8.65 mm × 3.90 mm), exposed thermal pad (to be tied to GND).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC5927IDBQR and STP16DP05PTR, the TLC5926IDBQR uniquely balances open-load diagnostics, 30 MHz throughput, and SSOP-24 compactness - making it optimal for space-constrained, fault-aware LED signage where short-circuit events are statistically rare.

Availability

TLC5926IDBQR is available at Aetrix Electronics and suitable for outdoor LED signage, industrial HMI panels, and architectural lighting arrays requiring stable component supply, long-term manufacturability, and guaranteed traceability.

Supply support for TLC5926IDBQR 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 components for industrial, automotive, and communications markets.

The TLC592x product line was engineered specifically for LED display and lighting systems demanding precise current regulation, integrated fault detection, and robust serial control - targeting applications where visual consistency and operational reliability are non-negotiable.

FAQ

What is the maximum output voltage tolerance of the TLC5926IDBQR?

The TLC5926IDBQR supports up to 17 V at its OUT0–OUT15 pins, allowing direct drive of multi-LED strings (e.g., five 3.2 V white LEDs) without intermediate voltage translation. This rating is absolute maximum and applies under normal operating conditions with proper thermal management. Exceeding 17 V risks permanent damage to the output transistors. The TLC5926IDBQR maintains constant current regulation across this full output voltage range, provided the external R-EXT resistor is correctly selected for the target current.

Does the TLC5926IDBQR support short-circuit detection?

No, the TLC5926IDBQR does not support short-circuit detection. That capability is exclusive to the TLC5927IDBQR variant. The TLC5926IDBQR implements only open-load detection and global/channel-specific overtemperature shutdown. When a short occurs at an output, the device will limit current via its constant-current regulation but will not flag it as an error condition. For applications requiring short-circuit diagnostics, the TLC5927IDBQR is the direct alternative with identical pinout and package.

How is output current adjusted on the TLC5926IDBQR?

Output current on the TLC5926IDBQR is set globally across all 16 channels using a single external resistor (R-EXT) connected to Pin 23. The nominal current per channel is calculated as IOUT = 12.5 V / R-EXT. For example, a 720 Ω resistor yields ~17.4 mA, while a 360 Ω resistor yields ~34.7 mA. The device also supports 256-step programmable global current gain (1/12 to 127/128) via Special Mode configuration codes sent through SDI, enabling fine calibration without hardware changes.

What are the key timing requirements for reliable serial communication with the TLC5926IDBQR?

Reliable serial operation requires CLK pulse width ≥20 ns, LE(ED1) pulse width ≥20 ns, and OE(ED2) pulse width ≥1000 ns in Normal Mode. Setup time for SDI relative to CLK is 7 ns minimum; hold time is 3 ns minimum. For cascaded configurations, maintain CLK rise/fall times ≤500 ns to prevent inter-device timing violations. The TLC5926IDBQR supports up to 30 MHz clock frequency, but signal integrity on PCB traces becomes critical above 10 MHz - use controlled impedance routing and minimize stub lengths.

Can the TLC5926IDBQR be used in daisy-chain configurations?

Yes, the TLC5926IDBQR supports daisy-chaining via its SDO (Pin 22) and SDI (Pin 2) pins. Serial data shifts in through SDI, propagates through the 16-bit shift register, and exits via SDO to the next device's SDI. This allows driving hundreds of LEDs with a single microcontroller GPIO pair. To ensure correct operation, the LE(ED1) signal must be asserted simultaneously across all chained devices to latch data into their respective output latches, and OE(ED2) must be controlled globally to enable/disable all outputs together.