# UC3844DTR

**Texas Instruments** · AC-DC Controllers And Regulators · SOIC-14

UC3844DTR from Texas Instruments, in a SOIC-14. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | COMP | output | Error amplifier compensation output with internal current limiting; external connection to GROUND forces zero duty cycle. |
| 2 | NC | unconnected | No connection. |
| 3 | VFB | input | Inverting input to error amplifier; used for output voltage regulation feedback control with input voltage 2.5V typical. |
| 4 | NC | unconnected | No connection. |
| 5 | ISENSE | input | Current sense input to PWM comparator with 3V/V gain; maximum input signal 1V at 5V COMP voltage. |
| 6 | NC | unconnected | No connection. |
| 7 | RT/CT | bidirectional | Oscillator timing pin for frequency setting with external RC network; switching frequency fOSC = 1.72 / (RRT × CCT) Hz with timing resistor 5-100kΩ and capacitor 1-100nF. |
| 8 | PWRGND | power_in | Power ground return for high-current gate driver output stage; separate from signal ground GROUND in 14-pin packages. |
| 9 | GROUND | power_in | Signal and analog ground for error amplifier and current detection circuits; serves as power and signal ground where PWRGND unavailable. |
| 10 | OUTPUT | output | Totem-pole gate driver output capable of sourcing and sinking peak current up to 1A to directly drive N-channel MOSFET; actively held low when VCC below UVLO threshold. |
| 11 | VC | power_in | Gate driver bias supply input for totem-pole output stage (14-pin packages only); requires bypass capacitor minimum 10× main switch MOSFET gate capacitance. |
| 12 | VCC | power_in | Main analog controller bias supply input voltage 12-28V recommended; total current equals static quiescent current plus average OUTPUT current (IOUTPUT = Qg × fSW). |
| 13 | NC | unconnected | No connection. |
| 14 | VREF | power_in | Internal precision 5V reference voltage output with ±2% tolerance for UC284x or ±1.8% for UC384x; requires 0.1µF minimum ceramic bypass capacitor with maximum short-circuit current ±30-180mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-14 |
| Category | Power Management (PMIC) |
| Pins | 14 |

## CAD (KiCad official)

- Symbol: `UC3844DTR`
- Footprint: `Package_SO:SOIC-14_3.9x8.7mm_P1.27mm`
- 3D model: SOIC-14 (KiCad packages3D, STEP)
- 3D model files: `uc3844dtr-etched.step` / `uc3844dtr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `uc3844dtr.step` / `uc3844dtr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/uc3842) (61 pp, sha256 `0f875fd24cbb5fda`, retrieved 2026-10-05, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-4-5-20251001` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).

[Datasheet PDF](docs/uc3844dtr-datasheet.pdf)