Texas Instruments TLC5941RHB

Overview

TLC5941RHB from Texas Instruments is a 16-channel constant-current LED driver IC with integrated 12-bit grayscale PWM control (4096 steps), 6-bit dot correction (64 steps), LED open detection (LOD), and thermal error flag (TEF). It operates from 3.0 V to 5.5 V supply, supports up to 80 mA per channel, and features serial interface (SIN/SCLK/SOUT) with 30 MHz data rate for high-resolution LED display systems.

For engineers reviewing the TLC5941RHB datasheet, TLC5941RHB pinout, TLC5941RHB application, or TLC5941RHB equivalent, key selection considerations include its QFN-32 package with PowerPAD™ thermal enhancement, programmable IREF-based current setting, cascaded serial architecture for multi-device systems, and dual-mode operation (GS/DC register loading via MODE pin).

Technical Context

The TLC5941RHB implements a dual-register architecture: 192-bit grayscale (GS) register for 12-bit per-channel PWM brightness control and 96-bit dot correction (DC) register for 6-bit per-channel current trimming. Grayscale timing is driven by external GSCLK (up to 30 MHz), while serial data is clocked via SCLK and latched using level-triggered XLAT.

It integrates two independent error reporting circuits: LOD detects open-circuit LEDs when OUTn voltage falls below 0.3 V (typical) during active drive, and TEF triggers at junction temperature >150 °C (spec'd), both asserted via open-drain XERR output. BLANK provides synchronous global output disable and GS counter reset.

Key Specifications

Pinout & Package

Package: 32-pin 5 mm × 5 mm QFN with exposed thermal pad (PowerPAD™), RoHS-compliant, rated for –40°C to +85°C ambient operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC5947RGER and IS31FL3728-QFLS4-TR, the TLC5941RHB uniquely combines hardware-level LED open detection, thermal flag reporting, and 80 mA per-channel drive in a compact QFN package - making it optimal for mission-critical outdoor signage and industrial displays where reliability and fault visibility are mandatory.

Availability

TLC5941RHB is available at Aetrix Electronics and suitable for LED signboards, full-color video walls, and architectural backlighting requiring stable component supply, long-term manufacturability, and guaranteed thermal performance under continuous operation.

Supply support for TLC5941RHB 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 TLC5941 product line was designed specifically for high-precision, high-density LED display systems demanding per-channel current matching, grayscale fidelity, and real-time fault diagnostics - targeting signage, instrumentation, and professional lighting.

FAQ

What is the maximum output current per channel for the TLC5941RHB?

The TLC5941RHB supports up to 80 mA per output channel (OUT0–OUT15), set by an external resistor connected between IREF and GND. With R_IREF = 640 Ω, the typical maximum current is 61 mA (±4% over temperature), and the device maintains ±1% channel-to-channel matching at that level. The TLC5941RHB datasheet specifies 80 mA as the absolute maximum DC output current rating.

How does the TLC5941RHB implement LED open detection (LOD)?

The TLC5941RHB monitors each OUTn pin during active drive; if the voltage drops below 0.3 V (typical) while the channel is enabled, LOD is triggered. This condition is reported immediately via the open-drain XERR pin and latched into the status register upon the next XLAT low-to-high transition. The TLC5941RHB requires BLANK = LOW and proper MODE/XLAT timing to capture and read LOD status via SOUT.

Can multiple TLC5941RHB devices be connected in series?

Yes - the TLC5941RHB supports daisy-chained configuration via its SOUT-to-SIN interface. Data shifted into the first device's SIN propagates through SOUT to the next device's SIN, allowing scalable channel expansion. Cascading requires matching GSCLK and BLANK across all devices, and XLAT must be asserted simultaneously to latch data across the chain. The TLC5941RHB's 30 MHz SCLK supports fast loading even in large chains.

What is the role of the MODE pin on the TLC5941RHB?

The MODE pin selects between two operating modes: when tied to GND, the TLC5941RHB accepts 192-bit grayscale (GS) data; when tied to VCC, it accepts 96-bit dot correction (DC) data. The TLC5941RHB requires MODE to be stable before and during XLAT assertion, and GS data must be loaded before DC data after power-up to prevent loss of the first GS bit. MODE is sampled on XLAT transitions, not continuously.

Does the TLC5941RHB require external pull-up resistors?

Yes - the TLC5941RHB requires external pull-up resistors on SOUT and XERR (open-drain outputs), and optionally on MODE and TEST (which must be tied to VCC). A typical 10 kΩ pull-up on XERR ensures clean logic-high reporting during normal operation; multiple TLC5941RHB units can share one pull-up via wired-OR connection. SOUT pull-up enables reliable status readback in daisy-chain configurations.