# MP172GJ-Z

**Monolithic Power Systems** · AC-DC Controllers And Regulators · TSOT-23-5

MP172GJ-Z from Monolithic Power Systems, in a TSOT-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 | VCC | power_in | Control-circuit power supply. Internally biased from DRAIN by the on-chip high-voltage start-up regulator; VCCOFF ~5.7 V (regulator stops charging), VCCON ~5.5 V (regulator restarts), VCCstop ~3.4 V (IC stops switching), VCCpro ~2.5 V. Bypass to SOURCE with a low-μF capacitor. |
| 2 | FB | input | Regulator feedback input. Sampled 6 μs after MOSFET turn-off and compared against the 2.55 V internal reference (VFB) to regulate the output; OLP triggers when VFB < ~1.74 V for 170 ms (at fS=36 kHz); open-loop detection triggers when VFB < ~0.5 V. |
| 3 | SOURCE | power_in | Internal power MOSFET source and ground reference for VCC and FB. Pins 3 and 4 are internally common and must both be tied to the primary-side return. |
| 4 | SOURCE | power_in | Internal power MOSFET source and ground reference for VCC and FB. Pins 3 and 4 are internally common and must both be tied to the primary-side return. |
| 5 | DRAIN | power_in | Internal 700 V power MOSFET drain and high-voltage start-up current source input. Ron ~16 Ω typ; V(BR)DSS 700 V; ILimit ~210 mA (peak), ISCP ~400 mA. Connect to the switching node / rectified high-voltage rail per topology. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Monolithic Power Systems |
| Package | TSOT-23-5 |
| Category | Power Management (PMIC) |
| Pins | 5 |

## Ordering variants

Same part, different packaging or reel option.

- `MP172GJ-Z`
- `MP172GJ-ZGS`
- `MP172GJ-ZGS-Z`

## CAD (KiCad official)

- Symbol: `MP172GJ-Z`
- Footprint: `Package_TO_SOT_SMD:TSOT-23-5`
- 3D model: TSOT-23-5 (KiCad packages3D, STEP)
- 3D model files: `mp172gj-z-etched.step` / `mp172gj-z-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `mp172gj-z.step` / `mp172gj-z.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Monolithic Power Systems datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8603388584217100288) (None pp, sha256 `3db857898bc6a74e`, 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/mp172gj-z-datasheet.pdf)