A 16-channel constant-current LED driver in HTSSOP-28, for driving LEDs at precise, uniform brightness. Each of the sixteen open-drain outputs sinks a programmed constant current (set by one external resistor), so LED brightness does not depend on forward-voltage spread, and each channel gets an individual 12-bit (4096-step) grayscale PWM value plus a 6-bit dot-correction trim to even out channel-to-channel differences. Data shifts in serially (SIN/SCLK/XLAT) and the outputs can be daisy-chained (SOUT) to drive dozens of channels from a few pins. It is a staple of RGB matrices, mood lighting, and video walls. The 3D model shown is a representative TSSOP-28 body; the real package is HTSSOP-28 with a thermal pad.

Pinout

Pin	Name	Type	Function
1	GND	power_in	Device ground / substrate return for the digital core and analog reference. Must be tied to the system ground plane; the HTSSOP thermal pad should also connect to GND for heat spreading.
2	BLANK	input	Blank-all-outputs control. When BLANK = H, all OUTn are forced OFF and the grayscale counter is reset. When BLANK = L, OUTn are driven under 12-bit grayscale PWM. CMOS input, VIH ≥ 0.8·VCC.
3	XLAT	input	Level-triggered latch signal. On XLAT high, shift-register data is latched into the GS register (VPRG = L) or DC register (VPRG = H). When XLAT is low, GS/DC data is held constant. Minimum pulse width 20 ns.
4	SCLK	input	Serial data shift clock for the input shift register (data on SIN sampled on rising edge). Supports data-rates up to 30 MHz; minimum H/L pulse width 16 ns.
5	SIN	input	Serial data input. Data is shifted into the 192-bit (GS) or 96-bit (DC) input shift register MSB-first on the rising edge of SCLK.
6	VPRG	input	Multifunction mode-select input. VPRG = GND → GS (grayscale) mode; VPRG = VCC → DC (dot correction) mode; VPRG = V(PRG) (20-23 V) with DCPRG = H → programs DC data into the on-chip EEPROM. Reset EEPROM default is 3Fh.
7	OUT0	output	Constant-current LED sink output 0. Sinks 0-60 mA (VCC < 3.6 V) or 0-120 mA (VCC > 3.6 V); modulated by 12-bit grayscale PWM × 6-bit dot correction. LED anode tied to LED supply (up to 17 V).
8	OUT1	output	Constant-current LED sink output 1. See OUT0.
9	OUT2	output	Constant-current LED sink output 2. See OUT0.
10	OUT3	output	Constant-current LED sink output 3. See OUT0.
11	OUT4	output	Constant-current LED sink output 4. See OUT0.
12	OUT5	output	Constant-current LED sink output 5. See OUT0.
13	OUT6	output	Constant-current LED sink output 6. See OUT0.
14	OUT7	output	Constant-current LED sink output 7. See OUT0.
15	OUT8	output	Constant-current LED sink output 8. See OUT0.
16	OUT9	output	Constant-current LED sink output 9. See OUT0.
17	OUT10	output	Constant-current LED sink output 10. See OUT0.
18	OUT11	output	Constant-current LED sink output 11. See OUT0.
19	OUT12	output	Constant-current LED sink output 12. See OUT0.
20	OUT13	output	Constant-current LED sink output 13. See OUT0.
21	OUT14	output	Constant-current LED sink output 14. See OUT0.
22	OUT15	output	Constant-current LED sink output 15. See OUT0.
23	XERR	output	Open-drain error flag output. Pulled low when either LED-open-detection (LOD) or thermal-error-flag (TEF) asserts. Requires an external pull-up to VCC (typ. 10 kΩ).
24	SOUT	output	Serial data output - end of the 192-bit shift register, allowing cascade of multiple TLC5940 devices. IOH = -1 mA, IOL = 1 mA (VCC = 5 V).
25	GSCLK	input	Reference clock for the internal 12-bit grayscale PWM counter. Up to 30 MHz; drives the 4096-step brightness ramp for all 16 channels.
26	DCPRG	input	Switch DC-data source. DCPRG = L → DC values read from EEPROM; DCPRG = H → DC values read from the DC register. In combination with VPRG = V(PRG) it initiates EEPROM programming (default 3Fh).
27	IREF	passive	Reference-current programming terminal. An external resistor from IREF to GND sets the maximum sink current for all 16 outputs; VREF ≈ 1.24 V. IOLC = 60 mA (VCC < 3.6 V) or 120 mA (VCC > 3.6 V).
28	VCC	power_in	Logic and analog supply voltage. Recommended operating range 3.0-5.5 V (abs-max 6 V). Bypass with a 100 nF ceramic close to the pin.

Key specifications

Parameter	Value
Type	16-channel constant-current LED driver
Channels	16 (open-drain current sinks)
Grayscale	12-bit PWM per channel
Dot correction	6-bit per channel
Current set	single external resistor
Interface	serial (SIN/SCLK/XLAT), cascadable
Supply voltage	3-5.5 V
Package	HTSSOP-28 (thermal pad)

Ordering variants

Same part, different packaging or reel option.

TLC5940PWP (HTSSOP-28)
TLC5940NT (PDIP-28)

CAD (KiCad official)

Symbol: Driver_LED:TLC5940PWP
Footprint: Package_SO:HTSSOP-28-1EP_4.4x9.7mm_P0.65mm
3D model: TSSOP-28 (representative; real package HTSSOP-28)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

Datasheet: Texas Instruments datasheet (40 pp, sha256 0177686922a94a12, retrieved 2026-08-17, tier: manufacturer)
Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF