Texas Instruments TLC5947DAPRG4

Overview

TLC5947DAPRG4 from Texas Instruments is a 24-channel, 12-bit PWM constant-current LED sink driver in a 32-pin HTSSOP package. It delivers up to 30 mA per channel with ±2% channel-to-channel current accuracy, integrated 4-MHz oscillator, and thermal shutdown protection. It drives static LED displays, message boards, and amusement lighting with serial grayscale control.

For engineers reviewing the TLC5947DAPRG4 datasheet, TLC5947DAPRG4 pinout, TLC5947DAPRG4 application, or TLC5947DAPRG4 equivalent, key selection criteria include its 24-channel sink architecture, 12-bit (4096-step) PWM resolution, internal clock operation, BLANK/XLAT timing control, and IREF-based current setting - all critical for high-fidelity LED brightness control without external clocking.

Technical Context

The TLC5947DAPRG4 implements a fully autonomous grayscale PWM engine: a 12-bit counter driven by an internal 4-MHz oscillator cycles every 4096 clocks (~1.024 ms), with each OUTn channel turning on at the fifth oscillator edge after BLANK↓ and turning off when its latched GS value matches the counter. Grayscale data (288 bits) are shifted in via SIN/SCLK and latched on XLAT↑.

It features grouped 6-channel soft-start (four groups staggered by ~15–99 ns propagation delays) to suppress inrush current and EMI, plus thermal shutdown that disables all outputs above 162°C (typ) and auto-restarts below T_TEF – T_HYS. All 24 outputs share one IREF resistor for unified current calibration.

Key Specifications

Pinout & Package

Package: HTSSOP-32 (DAP), 11.00 mm × 6.20 mm body with exposed thermal pad (bottom side).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC5947RHB, the TLC5947DAPRG4 offers superior board-level thermal dissipation margin in HTSSOP packaging, while MAX6967AUG+T trades integration for channel count reduction and external clock dependency - making TLC5947DAPRG4 optimal for medium-density, self-timed LED arrays.

Availability

TLC5947DAPRG4 is available at Aetrix Electronics and suitable for static LED displays, message boards, and amusement illumination requiring stable component supply, long-term production continuity, and TI-qualified automotive/industrial grade reliability.

Supply support for TLC5947DAPRG4 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 delivering analog, embedded processing, and connectivity solutions with deep expertise in power management and signal chain technologies.

The TLC5947 belongs to TI's LED driver product line, engineered specifically for high-accuracy, multi-channel constant-current PWM control in signage, display, and decorative lighting systems - emphasizing integration, thermal robustness, and ease of serial interface implementation.

FAQ

What is the maximum LED supply voltage supported by the TLC5947DAPRG4?

The TLC5947DAPRG4 supports up to 30 V applied to its OUT0–OUT23 pins, enabling direct drive of multi-LED strings (e.g., 6–8 white LEDs in series at ~3.2 V each). This rating is specified under Recommended Operating Conditions and remains valid across the full –40°C to +85°C temperature range. The device's output transistor breakdown voltage exceeds this, ensuring safe operation even with transient spikes.

How does the TLC5947DAPRG4 achieve 12-bit grayscale without an external clock?

The TLC5947DAPRG4 achieves autonomous 12-bit grayscale using its integrated 4-MHz internal oscillator, which drives a 12-bit counter cycling every 4096 clocks (~1.024 ms). Each output turns on at the fifth oscillator edge after BLANK↓ and turns off when its latched GS value matches the counter. This eliminates external clock dependencies while guaranteeing precise, jitter-free PWM timing for all 24 channels.

Can multiple TLC5947DAPRG4 devices be cascaded, and what is the data rate limitation?

Yes, multiple TLC5947DAPRG4 devices can be cascaded using SOUT-to-SIN connections. In cascade mode, the maximum SCLK frequency is 15 MHz (50% duty cycle), supporting full 288-bit data transfer to each device in <19.2 µs. Cascading preserves identical grayscale timing across all devices because the internal oscillator - not SCLK - governs PWM generation, preventing inter-device skew.

What is the purpose of the four-group output delay in the TLC5947DAPRG4?

The four-group output delay staggers turn-on/turn-off of the 24 channels into four sets of six (e.g., OUT0/4/8/12/16/20), with ~15–99 ns inter-group propagation delays. This reduces peak inrush current and di/dt-induced noise/EMI during grayscale transitions - critical for maintaining signal integrity in mixed-signal PCBs and meeting EMC standards in commercial lighting products.

How is output current calibrated on the TLC5947DAPRG4, and what tolerance should be expected?

Output current on the TLC5947DAPRG4 is calibrated by connecting a precision resistor between IREF (Pin 31) and GND. The nominal reference voltage is 1.20 V, so I_OUT = 1.20 V / R_IREF. At 30 mA full scale (R_IREF = 40 Ω), channel-to-channel matching is ±2% typical, and device-to-device variation is also ±2% - verified across production lots and operating temperatures from –40°C to +85°C.