Texas Instruments TLC5929PWP

Overview

TLC5929PWP from Texas Instruments is a 16-channel constant-current LED sink driver with 7-bit global brightness control (128 steps), ±1% typical channel-to-channel current accuracy, and integrated LED open/short detection. It operates from 3.0 V to 5.5 V supply voltage, supports up to 10 V LED supply, and delivers up to 50 mA per channel at VCC > 3.6 V - used in variable message signs and high-reliability LED illumination systems.

For engineers reviewing the TLC5929PWP datasheet, TLC5929PWP pinout, TLC5929PWP application, or TLC5929PWP equivalent, key selection criteria include its HTSSOP-24 PowerPAD™ package thermal performance (θJA = 37.6°C/W), invisible detection mode for LED faults during output-off states, 33 MHz serial data rate, and power-save mode consuming only 10 µA typical.

Technical Context

The TLC5929PWP implements a 17-bit serial shift register with dual 16-bit latches - one for output on/off control and one for function configuration (global brightness, LSD voltage select, error flags). Its constant-current sink architecture uses a single external IREF resistor to set maximum per-channel current, with line regulation of ±0.1%/V and load regulation of ±0.5%/V.

Error diagnostics include LED open detection (LOD) with 0.30 V threshold, four-level LED short detection (LSD) selectable via control latch bits, output leakage detection (OLD) sensitive to ≥3 µA, and thermal shutdown triggered at 150°C junction temperature with 10°C hysteresis.

Key Specifications

Pinout & Package

HTSSOP-24 PowerPAD™ package with exposed thermal pad on bottom side for enhanced heat dissipation (θJCbot = 5.7°C/W); 0.65 mm lead pitch, 7.8 mm × 4.4 mm body size.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC5940PWPR and MAX7219CWG+, the TLC5929PWP uniquely combines 16-channel constant-current sinking, ±1% matching, integrated LED fault detection, and 10 µA power-save mode - making it optimal for reliability-critical outdoor signage where maintenance access is costly.

Availability

TLC5929PWP is available at Aetrix Electronics and suitable for variable message signs, architectural LED illumination, and industrial control panels requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TLC5929PWP 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 U.S.-based semiconductor company specializing in analog and embedded processing technologies, with leadership in power management, signal chain, and high-reliability interface solutions.

The TLC5929 product line was designed specifically for high-density, fault-aware LED display systems - emphasizing thermal robustness, diagnostic completeness, and daisy-chain scalability in harsh environments.

FAQ

What is the maximum LED supply voltage supported by the TLC5929PWP?

The TLC5929PWP supports up to 10 V applied to its OUT0–OUT15 pins. This allows direct driving of multi-LED strings (e.g., three white LEDs in series at ~3.2 V each) without external boost circuitry. The absolute maximum rating is +11 V, but operation above 10 V risks exceeding safe operating area limits under high current conditions. Always verify VOUTn < (VCC − 0.3 V) + 10 V in layout design.

How does the TLC5929PWP achieve ±1% channel-to-channel current matching?

The TLC5929PWP achieves ±1% typical channel-to-channel current matching through matched internal current mirror transistor arrays and precision bandgap reference circuitry. Matching is maintained across temperature (–40°C to +85°C) and supply voltage (3.0 V to 5.5 V) due to on-die trimming and layout symmetry. The datasheet specifies ±3% maximum deviation, verified per unit during production test.

Can the TLC5929PWP detect LED faults while all outputs are disabled?

Yes, the TLC5929PWP supports invisible detection mode (IDM) for both LED open detection (LOD) and LED short detection (LSD). When enabled via control latch bits, these diagnostics operate even when BLANK is high and all OUTn are forced off. IDM uses internal biasing to measure leakage paths without activating LEDs - confirmed in Figure 6 and Section 7.3.3 of SBVS159B.

What thermal management advantages does the HTSSOP-24 PowerPAD™ package provide for the TLC5929PWP?

With θJCbot = 5.7°C/W and θJA = 37.6°C/W, the HTSSOP-24 PowerPAD™ package of the TLC5929PWP delivers 2.3× better junction-to-ambient thermal resistance than the SSOP-24 (DBQ) variant (θJA = 85.3°C/W). The exposed copper pad must be soldered to a dedicated PCB thermal plane with ≥4 thermal vias (0.3 mm diameter) to realize full benefit - enabling continuous 50 mA/channel operation at +85°C ambient.

How is global brightness control implemented in the TLC5929PWP?

Global brightness control in the TLC5929PWP uses a 7-bit value (0h–7Fh) stored in the control data latch to scale all 16 output currents linearly from 0% to 100% of the IREF-set maximum. Each step corresponds to ~0.78% increment; actual current is calculated as IOLCn = IOLCMax × BC/127. This occurs digitally within the current DAC path - no external PWM or analog dimming required.