# MD7733

**Shanghai Mingda Microelectronics** · DC-DC Converters · TO-92-3

MD7733 from Shanghai Mingda Microelectronics, in a TO-92-3. 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 | Vss | power_in | Ground pin (Vss/GND); absolute maximum Vout, CE and Lx voltages are referenced to Vss. |
| 2 | Vout | power_out | Output voltage monitoring pin that also supplies the internal circuit; absolute maximum is Vss-0.3 to Vss+12 V. |
| 3 | Lx | output | Switching pin connected to the inductor; absolute maximum is Vss-0.3 to Vss+12 V with ILX up to 1000 mA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Shanghai Mingda Microelectronics |
| Package | TO-92-3 |
| Category | Power Management (PMIC) |
| Pins | 3 |

## 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 | -2.5 |  | 2.5 | % |  | 3 |
| Input voltage | Vin |  |  | 10 | V |  | 3 |
| Start voltage | Vstart |  | 0.75 | 0.9 | V | Iout=1mA, Vin: 0→2V | 3 |
| Hold voltage | Vhold |  |  | 0.7 | V | Iout=1mA, Vin: 2→0V | 3 |
| Input current | Iin |  | 10 | 20 | uA | Iout=0mA | 3 |
| Quiescent power consumption | IDD |  | 4 | 7 | uA | VS = VOUT+0.5V | 3 |
| Shutdown current | ISHDN |  |  | 0.5 | uA | CE=GND | 4 |
| CE high-level voltage | VCEH | 2 |  |  | V |  | 4 |
| CE low-level voltage | VCEL |  |  | 0.4 | V |  | 4 |
| Switch leakage current | ILEAK |  |  | 0.5 | uA | VS = VOUT+0.5V, VX=6V | 4 |
| Duty cycle | DOSC | 65 | 75 | 85 | % | VS = VOUT*0.95 | 4 |
| Operating temperature range | Tmin-max | -20 |  | 80 | ℃ |  | 3 |
| Storage temperature range | Tstorage | -40 |  | 125 | ℃ |  | 3 |
| Lx current | ILX |  |  | 1000 | mA |  | 3 |
| Soldering temperature |  |  |  | 260 | ℃ | 10 S | 3 |
| Oscillation frequency | FOSC |  | 110 |  | kHz | VS = VOUT*0.95 | 4 |
| Efficiency | η |  | 85 |  | % |  | 4 |
| Nominal output voltage (MD7733 = 3.3V version) | VOUT |  | 3.3 |  | V | MD7733 variant | 2 |

## CAD (KiCad official)

- Symbol: `MD7733`
- Footprint: `Package_TO_SOT_THT:TO-92_Inline`
- 3D model: TO-92-3 (KiCad packages3D, STEP)
- 3D model files: `md7733-etched.step` / `md7733-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `md7733.step` / `md7733.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Shanghai Mingda Microelectronics datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8590225442310418432) (12 pp, sha256 `59f5984eab2f611d`, retrieved 2026-10-19, 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`, primary `claude-sonnet-5-5` (text+vision), consensus `claude-opus-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).

[Datasheet PDF](docs/md7733-datasheet.pdf)