# WS742128M-10

**WILLSEMI(Will Semicon)** · Audio Power OpAmps · MSOP-10

WS742128M-10 from WILLSEMI(Will Semicon), in a MSOP-10. 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 | -INR | input | Right-channel negative input; with RIN and RFB the voltage gain is RFB/RIN, with gain range ±1 V/V to ±10 V/V set by external resistors. |
| 2 | OUTR | output | Right-channel output; it can drive up to 220 pF directly, and higher capacitive loads require a series resistor of 47 Ω or larger. |
| 3 | EN | input | Active-high enable input with VIH of 1.1 V minimum and VIL of 0.4 V maximum; keep it low during supply ramp-up and ramp-down for pop-free power-up. |
| 4 | PVSS | power_in | Negative supply pin generated by the charge pump; its storage capacitor should be at least equal to the charge-pump capacitor, with a typical value of 1 µF. |
| 5 | CN | passive | Charge-pump flying capacitor negative terminal; a low-ESR X5R or X7R capacitor with a typical value of 0.33 µF is recommended. |
| 6 | CP | passive | Charge-pump flying capacitor positive terminal; a low-ESR X5R or X7R capacitor with a typical value of 0.33 µF is recommended. |
| 7 | PVDD | power_in | Positive supply pin; the single supply voltage range is 3.0 V to 5.5 V, with decoupling of 0.1 µF and 10 µF placed close to the pin. |
| 8 | UVP | input | External under-voltage protection input; the internal threshold VUVP is 1.14 V to 1.31 V (1.21 V typical), with a 4.7 µA hysteresis current, and the output is muted when the supply falls below the set level. |
| 9 | OUTL | output | Left-channel output; it can drive up to 220 pF directly, and higher capacitive loads require a series resistor of 47 Ω or larger. |
| 10 | -INL | input | Left-channel negative input; with RIN and RFB the voltage gain is RFB/RIN, with gain range ±1 V/V to ±10 V/V set by external resistors. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | WILLSEMI(Will Semicon) |
| Package | MSOP-10 |
| Category | Amplifiers |
| Pins | 10 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Supply Voltage | VDD | 3 | 5 | 5.5 | V | * full operating temperature range | 3 |
| Operating Temperature Range | TA | -40 |  | 85 | °C | * full operating temperature range | 3 |
| Output Offset Voltage | Vos | -3.5 | 0.6 | 3.5 | mV | VDD=3V to 5V, input grounded, unity gain; * full operating temperature range | 3 |
| External under-voltage detection | VUVP | 1.14 | 1.21 | 1.31 | V | VDD=3.3V | 3 |
| External under-voltage detection | VUVP | 1.14 | 1.21 | 1.31 | V | VDD=5V | 4 |
| Maximum output current | IO |  |  | 30 | mA | VDD=3.3V | 3 |
| Maximum output current | IO |  |  | 60 | mA | VDD=5V | 4 |
| Supply Voltage | VDD |  |  | 6 | V |  | 2 |
| Input Differential Voltage | VIDR |  |  | 6 | V |  | 2 |
| Operating Free-Air Temperature Range | TA | -40 |  | 85 | °C |  | 2 |
| Storage Temperature Range | TSTG | -65 |  | 150 | °C |  | 2 |
| Junction Temperature Range | TJ |  |  | 150 | °C |  | 2 |
| Lead Temperature Range | TL |  |  | 260 | °C |  | 2 |
| Thermal resistance, junction to ambient | ΘJA |  | 190 |  | °C/W | MSOP-10 package | 2 |

## CAD (KiCad official)

- Symbol: `WS742128M-10`
- Footprint: `Package_SO:MSOP-10_3x3mm_P0.5mm`
- 3D model: MSOP-10 (KiCad packages3D, STEP)
- 3D model files: `ws742128m-10-etched.step` / `ws742128m-10-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ws742128m-10.step` / `ws742128m-10.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [WILLSEMI(Will Semicon) datasheet](docs/ws742128m-10-datasheet.pdf) (13 pp, sha256 `426e3c066f094f53`, retrieved 2026-10-30, tier: lcsc)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-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/ws742128m-10-datasheet.pdf)