component
UC3845D
Public Made by Adomby adom
Texas Instruments AC-DC Controllers And Regulators, SOIC-14. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
3D Model
Open in new tab ↗
Loads on click. Unloads only if this page sits in the background.
Symbol & Footprint
Schematic Symbol
Open full view ↗Loads on click. Unloads only if this page sits in the background.
PCB Footprint
Open full view ↗Loads on click. Unloads only if this page sits in the background.
Datasheet
Open in new tab ↗Loads on click. Unloads only if this page sits in the background.
README
markdownUC3845D
Texas Instruments · AC-DC Controllers And Regulators · SOIC-14
UC3845D 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 pin for external compensation network connection to modify output voltage and enable pulse-by-pulse current limiting with internal current limit control. |
| 2 | NC | unconnected | No connection. |
| 3 | VFB | input | Error amplifier inverting input with -2µA input bias current accepting feedback voltage maximum 2.58V for voltage-loop control and closed-loop output regulation. |
| 4 | NC | unconnected | No connection. |
| 5 | ISENSE | input | Primary-side current-sense input to PWM comparator accepting maximum 1.0V nominal with -10µA input bias current and 150-300ns propagation delay for OUTPUT pulse termination. |
| 6 | NC | unconnected | No connection. |
| 7 | RT/CT | bidirectional | Oscillator timing pin with 1.7V peak-to-peak amplitude; connect timing resistor (5kΩ minimum) from VREF and timing capacitor (1nF to 100nF) to GROUND for programmable frequency 100-500kHz using fOSC = 1.72/(RRT×CCT). |
| 8 | PWRGND | power_in | Power stage ground providing high-current return path for output driver stage; requires direct connection to IC power devices for low-impedance connection. |
| 9 | GROUND | power_in | Analog signal ground serving as low-impedance reference for control circuits and power return path when separate PWRGND is not available. |
| 10 | OUTPUT | output | Gate driver output capable of sourcing and sinking ±1A peak current with 25-150ns rise and fall time for direct MOSFET gate drive; actively held low when VCC below turn-on threshold. |
| 11 | VC | power_in | Bias power supply input for output gate driver stage (14-pin SOIC variant only); requires bypass capacitor value at least 10 times the main switch FET gate capacitance. |
| 12 | VCC | power_in | Device power supply input requiring 12V to 28V operating range; total supply current equals static ICC (11-17mA) plus average output driver current; requires 0.1µF ceramic bypass capacitor. |
| 13 | NC | unconnected | No connection. |
| 14 | VREF | power_in | 5V ±2% precision reference voltage output (4.9-5.1V for UC384x) with 180mA short-circuit current capability, 50μV output noise, and 0.1µF ceramic bypass capacitor required. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-14 |
| Category | Power Management (PMIC) |
| Pins | 14 |
CAD (KiCad official)
- Symbol:
UC3845D - Footprint:
Package_SO:SOIC-14_3.9x8.7mm_P1.27mm - 3D model: SOIC-14 (KiCad packages3D, STEP)
- 3D model files:
uc3845d-etched.step/uc3845d-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);uc3845d.step/uc3845d.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: Texas Instruments datasheet (61 pp, sha256
0f875fd24cbb5fda, retrieved 2026-10-06, 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, primaryclaude-haiku-4-5-20251001(text), consensusclaude-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).