component
UC3845D8
Public Made by Adomby adom
Texas Instruments AC-DC Controllers And Regulators, SOIC-8. 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
markdownUC3845D8
Texas Instruments · AC-DC Controllers And Regulators · SOIC-8
UC3845D8 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 | COMP | output | Error amplifier compensation pin for external compensation elements; internally current-limited, can be forced to GROUND to control zero duty cycle. |
| 2 | VFB | input | Inverting input to internal error amplifier for controlling power converter voltage feedback loop and stability. |
| 3 | ISENSE | input | Primary-side current sensing input connected to current sense resistor; PWM uses this signal to terminate OUTPUT switch conduction and can accept voltage ramp for voltage-mode control. |
| 4 | RT/CT | bidirectional | Timing pin for fixed-frequency oscillator; connect timing resistor RRT to VREF and timing capacitor CCT to GROUND to set switching frequency. |
| 5 | GROUND | power_in | Analog ground serving as both power ground and signal return; for packages without separate PWRGND, serves dual function as power and analog ground. |
| 6 | OUTPUT | output | Gate driver output for external MOSFET; provides and sinks peak current up to 1A; actively held low when VCC is below turn-on threshold. |
| 7 | VCC | power_in | Analog controller bias supply input; total current is static current plus average OUTPUT current; requires 0.1µF bypass capacitor directly to GROUND with minimum wiring length. |
| 8 | VREF | power_in | 5V precision reference voltage output; provides charging current to oscillator timing capacitor through timing resistor; requires 0.1µF ceramic bypass capacitor to GROUND for stability. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |
CAD (KiCad official)
- Symbol:
UC3845D8 - Footprint:
Package_SO:SOIC-8_3.9x4.9mm_P1.27mm - 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files:
uc3845d8-etched.step/uc3845d8-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);uc3845d8.step/uc3845d8.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 2026-10-03, 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).