# UCC35706D

**Texas Instruments** · AC-DC Controllers And Regulators · SOIC-8

UCC35706D from Texas Instruments, in a SOIC-8. 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 | ILIM | input | Provides pulse-by-pulse current limit by terminating the PWM pulse when the input is above 200 mV, with a 25 ns typical high-speed path to reset the PWM latch; the datasheet lists a 180 mV to 220 mV current-limit threshold and an absolute maximum input voltage of 7 V. |
| 2 | FB | input | Input to the PWM comparator intended to interface with an optocoupler, with 50 kΩ typical input impedance and an absolute maximum input voltage of 15 V. |
| 3 | VFF | input | Feed-forward pin that provides a voltage proportional to the input supply, and both the output and oscillator are disabled when VFF is below 1.0 V; the absolute maximum input voltage is 7 V. |
| 4 | DISCH | input | A resistor to VIN sets the oscillator discharge current, which must be between 25 µA and 250 µA over the entire VIN range; grounding this pin disables the duty cycle clamp, and the absolute maximum input current is 1 mA. |
| 5 | RC | passive | Oscillator timing node connected to CT, where the on-time is set by RT and CT and the off-time by RDISCH and CT; the absolute maximum input voltage is 7 V. |
| 6 | GND | power_in | Ground return pin to which all voltages are referenced. |
| 7 | OUT | output | Drives an external FET driver or other high-impedance circuit and is not intended to directly drive a power MOSFET; the absolute maximum dc output current is ±20 mA. |
| 8 | VDD | power_in | Power supply pin that should be bypassed with a 0.1 µF capacitor; the absolute maximum supply voltage is 15 V and the UCC35706 UVLO start threshold is 12.0 V typical with a 8.0 V typical stop threshold. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `UCC35706D`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `ucc35706d-etched.step` / `ucc35706d-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ucc35706d.step` / `ucc35706d.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/ucc25705) (23 pp, sha256 `121bdd15995942af`, retrieved 2026-10-09, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (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/ucc35706d-datasheet.pdf)