Texas Instruments TLC5924RHBR

Overview

TLC5924RHBR from Texas Instruments is a 16-channel constant-current LED sink driver with integrated dot correction (7-bit per channel), pre-charge FETs, LED open detection (LOD), and thermal error flag (TEF). It delivers precise current control (±1% typical accuracy) across all 16 outputs, supports up to 80 mA per channel, operates from 3.0 V to 5.5 V supply, and features 30 MHz serial interface for high-speed data transfer. It is used in dynamic-drive LED displays requiring uniform brightness and fast refresh.

For engineers reviewing the TLC5924RHBR datasheet, TLC5924RHBR pinout, TLC5924RHBR application, or TLC5924RHBR equivalent, key selection considerations include its 32-pin VQFN (RHB) package, dual-mode serial interface (ON/OFF vs. dot-correction), LOD/TEF error reporting via open-drain XERR, and pre-charge FET timing for improved image quality in multiplexed LED signage.

Technical Context

The TLC5924RHBR implements two independent 16-bit shift register paths-16-bit for ON/OFF control and 112-bit (16 × 7) for dot correction-selected by the MODE pin. Its constant-current sinks are calibrated using a single external IREF resistor and internal 1.24 V reference, enabling scalable output current (0–80 mA) with ±1% typical channel-to-channel matching.

Each output includes a dedicated pre-charge FET activated during BLANK=H, with fixed 20 ns inter-channel delay to limit inrush current. Error detection is implemented via open-drain XERR, which asserts low on either LOD (output voltage < 0.3 V while ON) or TEF (junction temperature > 160 °C), and supports cascaded monitoring.

Key Specifications

Pinout & Package

Package: 32-pin VQFN (RHB), 5 mm × 5 mm body, 0.5 mm pitch, thermally enhanced with exposed PowerPAD™ on underside.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC5940RHBR and IS31FL3728-QFLS4-TR, the TLC5924RHBR uniquely combines pre-charge FETs, LOD/TEF diagnostics, and 30 MHz daisy-chainable SPI for high-reliability, high-refresh-rate LED signage - making it optimal where image integrity and fault resilience are critical.

Availability

TLC5924RHBR is available at Aetrix Electronics and suitable for monocolor signboards, multicolor video walls, dynamic backlighting systems, and industrial indicator panels requiring stable component supply and long-term production continuity.

Supply support for TLC5924RHBR 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 connectivity technologies with over 50 years of innovation in power management and signal chain ICs.

The TLC5924RHBR belongs to TI's LED driver product line, designed specifically for high-reliability, high-density LED display systems requiring per-channel current precision, real-time fault monitoring, and robust multiplexed timing control.

FAQ

What is the maximum output current per channel for the TLC5924RHBR?

The TLC5924RHBR supports up to 80 mA per channel, set by an external resistor connected between IREF and GND. Using the internal 1.24 V reference and 40× scaling factor, a 600 Ω resistor yields ~83 mA (I_MAX = 40 × 1.24 V / 600 Ω). The datasheet specifies 80 mA as the guaranteed maximum under recommended conditions, with ±1% typical current accuracy across all 16 channels when operating within –40 °C to +85 °C.

How does the TLC5924RHBR implement LED open detection (LOD)?

The TLC5924RHBR detects open LEDs by monitoring each OUTn voltage while the channel is commanded ON and BLANK is low. If the voltage drops below 0.3 V (typical), the LOD flag for that channel activates. Detected faults are reported collectively via the open-drain XERR pin or individually via 16-bit serial readout on SOUT after XLAT-triggered latching. The LOD status becomes valid 1.06 µs after BLANK goes low for OUT0, with 30 ns increments per subsequent channel due to internal delay staging.

Can the TLC5924RHBR be used in daisy-chained configurations?

Yes, the TLC5924RHBR supports daisy-chaining via its SOUT pin, which outputs shifted data after internal register loading. To cascade n devices, connect SOUT of device N to SIN of device N+1, share SCLK and XLAT, and use MODE to configure all devices in the same data mode (ON/OFF or dot correction). The minimum SCLK frequency required is f_SCLK = 112 × f_update × n for dot-correction updates, where n is the number of cascaded TLC5924RHBR units.

What is the role of the VUP pins on the TLC5924RHBR?

The TLC5924RHBR has two VUP pins (6 and 27) that supply the pre-charge FETs. These pins must be connected to a common 3 V–15 V rail - separate from VCC - to enable fast pre-charging of LED segment lines before sink activation. When VUP is unconnected or below 3 V, all OUTn remain high-impedance. Both VUP pins require low-inductance routing to the same supply to ensure simultaneous pre-charge FET turn-on and avoid timing skew across the 16 channels.

Does the TLC5924RHBR support both ON/OFF control and dot correction simultaneously?

No - the TLC5924RHBR uses the MODE pin to select between two mutually exclusive operating modes: MODE = L configures the serial interface for 16-bit ON/OFF data (latched on XLAT rising edge), while MODE = H configures it for 112-bit dot-correction data (latched while XLAT is high). Dot correction values persist across ON/OFF updates, allowing brightness calibration to be set once and maintained during dynamic content changes.