addressable.wiki
5.4 × 5.0 mm 4 pins top-emitting

T78

5050 · smd · TCWIN T78 · TCWIN

1-wire RGB 3.5–5.5 V active

At a glance

Colour
RGB8 bits per channel
Data
1-wiretimed pulses on one line
Supply
3.5–5.5 Vno backup data line
Size
5.4 × 5.0 × 1.6 mm4 pins · top
Max current
49.5 mA16.5 mA per channel
PWM
4 kHzreset 80 µs
Library support
FastLED WLED Adafruit

TCWIN T78: a 5050 four-pad LED driven at 16.5 mA per channel (15-18), 5 V supply, cover rating 0.18 W, version A5 dated 2024-08-29. Pins 1 VDD, 2 GND, 3 DO, 4 DIN - note GND and DO are swapped compared with every other four-pad 5050 TCWIN sheet (1 VDD, 2 DO, 3 GND, 4 DIN). Timing T0H 250/300/350 ns, T0L 800/900/1000 ns, T1H 800/900/1000, T1L 250/300/350, reset 80 us; DO drive is only 8 mA source and sink. The drawing carries only pin numbers (as on the other 5050 sheets), so the pad positions are the common ones and the signal assignment comes from the pin table; check it before laying out a board.

Variants

One row per orderable SKU. Everything not listed is inherited from the part above.

Order codeFaceLensWhite PinsSiliconStatusFirst seenDatasheet
T78 — — — 4 — active 2024-08-29 A5
LCSC stock 705 on 2026-10-15.

Pinout

T78
T78 5050 package, top and side viewPin 1 is ringed. pin 1 VDD (power), pin 2 GND (ground), pin 3 DO (data out), pin 4 DIN (data in).11 VDDpower22 GNDground33 DOdata out44 DINdata in5.4 mm overall5.0 mmtop view1.6 mmside view
  • Power
  • Ground
  • Data
  • Pin 1
  • Cut corner

Outline and pin positions checked against the manufacturer datasheet (C48982531 T78 rev A5 p4). Pin 1 is top-left, numbering runs counter-clockwise, and the chamfer sits at pin 3 (GND), as in the WS2812B. The sheet marks "+" on the pin 1-2 side and "-" on the pin 3-4 side. Pad sizes read from the drawing; the part spans 5.4 mm across the leads. What this means.

  1. 1 VDD power
  2. 2 GND ground
  3. 3 DO data out
  4. 4 DIN data in

Protocol — TCWIN T78

Timings shown from datasheet.

TCWIN T78 bit timingTCWIN T78 bit timing: a zero bit is 300 nanoseconds high then 900 low; a one bit is 900 high then 300 low; reset 80 microseconds low1 · Bit encoding, to scaleDINhighlowbit 0 period 1200 nsbit 1 period 1200 nsT0H 300 nsT1H 900 nsT0L 900 nsT1L 300 ns"0" bit"1" bit020040060080010001200140016001800200022002400time, ns2 · One frame: 24 bits, most-significant bit firstDIN170110010007100110101700101100bitch 1 · 8 bitsch 2 · 8 bitsch 3 · 8 bitsChannel order not recorded for this protocol · frame = 24 × ~1200 ns ≈ 28.8 µs · example data, first bits 1 0 1 …3 · RESET / latchlast bits of frame 1first bits of frame 2LEDs latch the data they receivedRESET: DIN low ≥ 80 µs (not to scale)4 · Cascade: each DOUT feeds the next DINMCULED 1DINDOUTLED 2DINDOUTLED NDINDOUTLED 1 keeps the first 24 bits, re-shapes the signal and sends the rest out on DOUT;LED 2 keeps the next 24, and so on. The last LED's DOUT is left unconnected.
T0H 300 / T0L 900 · T1H 900 / T1L 300 ns · period 1200 ns · reset 80 µs source: datasheet

Dating evidence

Nobody announces these parts, so this records what we can actually cite rather than a release date. Library support proves only that the part existed by that date.

  • 2024-08-29 datasheet revision TCWIN T78 specification cover: date 20240829, version A5 ↗ day

Where to buy

Stub data — a few rows so purchase links can grow later. Prices are not tracked.

Similar parts

Same protocol or package first, then the same data scheme and colour channels.

Was this page useful?

0 people found this useful