# UL66CG-06-AB3-R

**UTC Unisonic Tech** · LED Drivers · SOT-89

UL66CG-06-AB3-R from UTC Unisonic Tech, in a SOT-89. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | OUT | output | Current output pin. Connects to the cathode of the LED string; sinks the regulated constant current (5-60mA) set by REXT. Withstands up to 450V when IOUT=0; drops ~6.5V at IOUT=30mA. |
| 2 | GND | power_in | Ground reference for the device. Return path for internal LDO and current-sense circuitry. |
| 3 | REXT | input | Output current setting pin. An external resistor from REXT to GND programs the constant output current; VREXT is regulated to 0.6V typical (IOUT ≈ 0.6V / REXT). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | UTC Unisonic Tech |
| Package | SOT-89 |
| Category | LED-drv |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `UL66CG-06-AB3-R`
- `UL66CG-06-AB3-RAA3`
- `UL66CG-06-AB3-RTN3`

## CAD (KiCad official)

- Symbol: `UL66CG-06-AB3-R`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89 (KiCad packages3D, STEP)
- 3D model files: `ul66cg-06-ab3-r-etched.step` / `ul66cg-06-ab3-r-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ul66cg-06-ab3-r.step` / `ul66cg-06-ab3-r.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [UTC Unisonic Tech datasheet](docs/ul66cg-06-ab3-r-datasheet.pdf) (4 pp, sha256 `137cf1e91d08342f`, 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](docs/ul66cg-06-ab3-r-datasheet.pdf)