# RY3750

**RYCHIP** · DC-DC Converters · SOT-23-5

RY3750 from RYCHIP, in a SOT-23-5. 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 | LX | output | Power switch output. Drain of the internal N-channel MOSFET switch; connect the boost inductor and Schottky rectifier here. Node swings between GND and up to 30V at 1.2MHz. |
| 2 | GND | power_in | Device ground return. Tie to a solid ground plane for heat sinking and noise protection. |
| 3 | FB | input | Feedback input for the output voltage regulation loop. Internal reference is 1.23V (typical); set VOUT with an external resistor divider from VOUT to FB to GND. FB bias current is -50 to -10 nA. |
| 4 | EN | input | Regulator on/off enable input. Logic high (>~1V) turns the converter on; logic low turns it off (shutdown IIN ~0.1 uA). Tie to VIN for automatic startup when not used. Absolute max 6V. |
| 5 | IN | power_in | Input supply pin, 2.5V to 5.5V operating (abs max 6V). Must be locally bypassed with a low-ESR ceramic capacitor (22uF recommended, X5R/X7R). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | RYCHIP |
| Package | SOT-23-5 |
| Category | PMIC |
| Pins | 5 |

## Ordering variants

Same part, different packaging or reel option.

- `RY375070390005`

## CAD (KiCad official)

- Symbol: `RY3750`
- Footprint: `Package_TO_SOT_SMD:SOT-23-5`
- 3D model: SOT-23-5 (KiCad packages3D, STEP)
- 3D model files: `ry3750-etched.step` / `ry3750-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ry3750.step` / `ry3750.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [RYCHIP datasheet](docs/ry3750-datasheet.pdf) (7 pp, sha256 `3c00582ad13b7c1a`, retrieved 2026-08-17, tier: lcsc)
- **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](docs/ry3750-datasheet.pdf)