# MD8312

**Shanghai Mingda Microelectronics** · Voltage Regulators - Linear, Low Drop Out (LDO) Regulators · SOT-89-3

MD8312 from Shanghai Mingda Microelectronics, in a SOT-89-3. 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 | VOUT | power_out | Regulated 12V output. Drive with a >=1.0uF low-ESR ceramic capacitor to GND placed close to the pin. Maximum output current 300mA (typ), current-limited around 550mA with foldback. Must not exceed VIN+0.3V or the internal parasitic diode will conduct. |
| 2 | GND | power_in | Device ground / return. Quiescent GND current is ~1.5uA (no load) and rises with IOUT (typ 460uA at IOUT=100mA). SOT89 heat-slug tab; connect to the ground plane for thermal dissipation (PD=1000mW, RθJB=100 °C/W). |
| 3 | VIN | power_in | Unregulated input supply, 2.2V to 40V (absolute max 45V). Bypass with a >=1.0uF ceramic capacitor to GND close to the pin to avoid oscillation. For the 12V output variant VIN must be at least VOUT + dropout (~1.3V typ at 300mA). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shanghai Mingda Microelectronics |
| Package | SOT-89-3 |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

Same part, different packaging or reel option.

- `MD8312`
- `MD8312A`

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output voltage accuracy | VOUT | -2 |  | 2 | % |  | 2 |
| Input Voltage | VIN | 2.2 |  | 40 | V |  | 3 |
| GND Current | IGND | 1.5 | 2.3 | 3.5 | uA | no load, VOUT(S)>5.3V | 3 |
| Load Regulation | VOUT |  | 50 | 80 | mV | VIN=VOUT(S)+2V, 1mA≤IOUT≤300mA, VOUT(S)>5.3V | 3 |
| Line Regulation | ΔVOUT/ΔVIN |  | 0.01 | 0.02 | %/V | VOUT(S)+2V≤VIN≤40V, IOUT=1mA | 3 |
| Temperature Stability |  | -50 |  | 50 | ppm/℃ | VIN = VOUT(S)+2V, IOUT=10mA, -40℃≤Ta≤125℃ | 3 |
| Maximum Output Current | IOUTMAX |  | 300 | 350 | mA |  | 3 |
| Current Limit | ILIM |  | 350 | 550 | mA | VIN= VOUT(S)+2V, VOUT = 0.95×VOUT(S) | 3 |
| Thermal Resistance Junction-to-Board | RθJB |  | 100 |  | ℃/W | SOT89-3, mounted on JEDEC standard 4-layer (2s2p) PCB | 2 |
| Input Voltage (absolute maximum) | VIN | -0.3 |  | 45 | V |  | 2 |
| Power Dissipation | PD |  |  | 1000 | mW | SOT89-3 | 2 |
| Operating Ambient Temperature | Topr | -40 |  | 85 | ℃ |  | 2 |
| Storage Temperature | Tstg | -40 |  | 125 | ℃ |  | 2 |
| ESD Protection | ESD HBM |  |  | 1500 | V | HBM | 2 |

## CAD (KiCad official)

- Symbol: `MD8312`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89-3 (KiCad packages3D, STEP)
- 3D model files: `md8312-etched.step` / `md8312-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `md8312.step` / `md8312.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Shanghai Mingda Microelectronics datasheet](docs/md8312-datasheet.pdf) (10 pp, sha256 `b90bf74c0495d786`, 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/md8312-datasheet.pdf)