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Contents

README

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UCC3809D-2

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

UCC3809D-2 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 FB input Summing node for current sense feedback, optocoupler voltage feedback and slope compensation, compared to a 1V threshold, with an internal 250 ohm NMOS discharging any external filter capacitor during PWM off time.
2 SS bidirectional Soft start pin where the timing capacitor is charged by an internal 6µA source, and taking it below 0.5V inhibits the output driver, turns off the 5V reference and drops IVDD below 100µA.
3 RT1 passive Connects to timing resistor RT1 that sets the oscillator positive ramp time Tr = 0.74 x (CT + 27pF) x RT1, with a recommended minimum of 10kΩ.
4 RT2 passive Connects to timing resistor RT2 that sets the oscillator negative ramp time Tf = 0.74 x (CT + 27pF) x RT2, with a recommended minimum of 4.32kΩ.
5 GND power_in Reference ground and power ground for all functions.
6 OUT output High current totem pole power driver output (0.4A source/0.8A sink) for N-channel MOSFETs, with a minimum series gate resistor of 3.9 ohms recommended.
7 VDD power_in Power input shunt regulated at 17.5V (absolute maximum 19V) that should be bypassed with a 1µF ceramic capacitor.
8 REF power_out Internal buffered 5V reference output (4.75V to 5.25V) that should be bypassed with a 0.47µF ceramic capacitor.

Key specifications

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

CAD (KiCad official)

  • Symbol: UCC3809D-2
  • Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
  • 3D model: SOIC-8 (KiCad packages3D, STEP)
  • 3D model files: ucc3809d-2-etched.step / ucc3809d-2-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); ucc3809d-2.step / ucc3809d-2.glb are the bare package body.

Provenance

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

  • Datasheet: Texas Instruments datasheet (24 pp, sha256 7fc852aa75a77966, retrieved 2026-10-08, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-sonnet-5-5 (text+vision), consensus claude-opus-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