UC3842BD1R2G
Public Made by Adomby adom
onsemi AC-DC Controllers and Regulators, SOIC-8. Pinout extracted from the datasheet, KiCad symbol/footprint/3D.
UC3842BD1R2G
onsemi · AC-DC Controllers and Regulators · SOIC-8
UC3842BD1R2G from onsemi, 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 | Compensation | output | Error amplifier output made available for loop compensation. External compensation network is tied between this pin and the Voltage Feedback input (pin 2). |
| 2 | Voltage Feedback | input | Inverting input of the error amplifier. Normally connected to the switching power supply output through a resistor divider; nominal reference at this node is 2.5 V. |
| 3 | Current Sense | input | Non-inverting input of the current-sense comparator. A voltage proportional to inductor/switch current is applied here; peak current-sense threshold is typically 1.0 V (max) for cycle-by-cycle limiting. |
| 4 | RT/CT | passive | Oscillator timing pin. An external resistor to Vref and a capacitor to ground set the oscillator frequency and maximum output duty cycle. Guaranteed oscillator frequency up to 250 kHz; operational to 500 kHz. |
| 5 | GND | power_in | Device ground and return for both control-signal and high-current output-driver return paths (single-ground SOIC-8 / PDIP-8 variant). |
| 6 | Output | output | High-current totem-pole PWM gate-drive output for directly driving a power MOSFET. Rated 1.0 A source/sink; typical rise/fall times of 50 ns into 1.0 nF. |
| 7 | VCC | power_in | Positive supply voltage for control logic and output driver. UC3842B UVLO turn-on at 16 V (typ) and turn-off at 10 V (typ); maximum rating 30 V. Internal 36 V zener clamp (ICC = 25 mA). |
| 8 | Vref | power_out | Trimmed and temperature-compensated 5.0 V reference output. Typically capable of sourcing 20 mA to external circuitry and provides the pull-up for the RT/CT oscillator resistor. Short-circuit current limited to approximately 85 mA (typ). |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | onsemi |
| Package | SOIC-8 |
| Category | PMIC |
| Pins | 8 |
Ordering variants
Same part, different packaging or reel option.
UC3842BD1R2GUC3842BD1R2GD1GUC3842BD1R2GNUC3842BD1R2GNGUC3842BD1R2GDUC3842BD1R2GDGUC3842BD1R2GDR2G
CAD (KiCad official)
- Symbol:
UC3842BD1R2G - Footprint:
Package_SO:SOIC-8_3.9x4.9mm_P1.27mm - 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files:
uc3842bd1r2g-etched.step/uc3842bd1r2g-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);uc3842bd1r2g.step/uc3842bd1r2g.glbare the bare package body.
3D model downloads
Two STEP files. Same geometry, different body top:
| File | Size | Use it when |
|---|---|---|
uc3842bd1r2g.step |
122 KB | You want the bare part, or you mark your own boards. |
uc3842bd1r2g-etched.step |
2.8 MB | You want the part with UC3842BD1R2G already on it. |
The marking in the etched file is real recessed geometry cut into the solid, not a texture or a decal: 678 faces against 147 in the bare model. It survives export, section views, and rendering in any CAD tool, and it drops straight into KiCad or Fusion with no extra setup.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: onsemi datasheet (22 pp, sha256
581ae31fbd1f3e07, 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).