# MD52E21QA3

**Shanghai Mingda Microelectronics** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-23-3L

MD52E21QA3 from Shanghai Mingda Microelectronics, in a SOT-23-3L. 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 | GND | power_in | Device ground reference. Connect to system ground plane; place input and output ceramic capacitors as close as possible to this pin. |
| 2 | VOUT | power_out | Regulated 2.1V output (VOUT(S)=2.1V, tolerance +/-2%). Delivers up to 500mA (typ), current-limited at ~750mA with foldback to ~50mA under short circuit. Requires >=1.0uF low-ESR ceramic output capacitor for stability. |
| 3 | VIN | power_in | Unregulated input supply, 2.2V to 7.0V operating (absolute max 8V). Requires >=1.0uF ceramic input capacitor placed close to the pin. VOUT must not exceed VIN+0.3V to avoid parasitic-diode reverse conduction. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shanghai Mingda Microelectronics |
| Package | SOT-23-3L |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `MD52E21QA3`
- `MD52E21QA3QC3`
- `MD52E21QA3PA1`
- `MD52E21QA3WB6`

## CAD (KiCad official)

- Symbol: `MD52E21QA3`
- Footprint: `Package_TO_SOT_SMD:SOT-23-3`
- 3D model: SOT-23-3L (KiCad packages3D, STEP)

## Provenance

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

- **Datasheet:** [Shanghai Mingda Microelectronics datasheet](docs/md52e21qa3-datasheet.pdf) (14 pp, sha256 `11f4b5d8b0feb201`, 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/md52e21qa3-datasheet.pdf)