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UCC28C42DR

Texas Instruments · DC-DC Converters · SOIC-8

UCC28C42DR from Texas Instruments, in a SOIC-8. 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 COMP output Error amplifier output for loop compensation. Also usable as a control port via an opto-isolator from a secondary-side error amplifier. Internally current-limited; forcing COMP to GND commands zero duty cycle.
2 FB input Inverting input of the internal error amplifier used to close the power converter voltage-feedback loop. The non-inverting input is internally trimmed to 2.5V ±1%.
3 CS input Primary-side current sense pin; non-inverting input to the PWM comparator. Connect to the current-sensing resistor; the PWM terminates the OUT switch conduction when CS exceeds the scaled error-amplifier signal. Can also be driven by a voltage ramp for voltage-mode operation.
4 RT/CT bidirectional Fixed-frequency oscillator set point. Connect RRT to VREF and CCT to GND to set fSW. For UCC28C42, gate-drive fSW equals fOSC. Keep CCT lead to GND short; a separate ground trace for CCT is recommended.
5 GND power_in Ground return for the output driver stage and the logic-level controller section. All voltages in the datasheet are referenced to this pin.
6 OUT output Gate-drive output of the on-chip rail-to-rail driver, intended to directly drive an external MOSFET. Sources and sinks up to ±1A peak (25ns rise / 20ns fall). Runs at fOSC and can operate near 100% duty cycle on the UCC28C42; held actively low when VDD is below the turn-on threshold.
7 VDD power_in Analog controller bias input; supplies the whole device. UVLO turn-on 14.5V, turn-off 9V. Absolute max 20V; recommended max 18V. Bypass with 0.1µF directly to GND, plus additional capacitance ≥10× the driven FET's gate capacitance.
8 VREF power_out 5V ±1% internal reference output (typ 5V, 4.9-5.1V at TJ=25°C). Used to charge the oscillator timing capacitor through RRT and to bias external circuitry (≤20mA source). Bypass to GND with ≥0.1µF ceramic close to the pin. Short-circuit source current 30-55mA.

Key specifications

Parameter Value
Manufacturer Texas Instruments
Package SOIC-8
Category PMIC
Pins 8

Ordering variants

  • UCC28C42DRD
  • UCC28C42DR
  • UCC28C42DRDGK
  • UCC28C42DRDGKR

CAD (KiCad official)

  • Symbol: UCC28C42DR
  • Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
  • 3D model: SOIC-8 (KiCad packages3D, STEP)

Provenance

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

  • Datasheet: Texas Instruments datasheet (None pp, sha256 9fa55f996731c56b, 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

Symbol & Footprint

Schematic Symbol

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PCB Footprint

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