# INA4181A1QPWRQ1

**Texas Instruments** · Current Sense Amplifiers · TSSOP-20

INA4181A1QPWRQ1 from Texas Instruments, in a TSSOP-20. 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 | REF1 | input | Channel 1 reference voltage input (range 0V to VS); sets the zero-current output level for bidirectional current sensing |
| 2 | OUT1 | output | Channel 1 analog output voltage proportional to sensed current magnitude and direction |
| 3 | IN-1 | input | Channel 1 negative current sensing input; connect to load side of sense resistor (high-side) or ground side (low-side) |
| 4 | IN+1 | input | Channel 1 positive current sensing input; connect to bus voltage side of sense resistor (high-side) or load side (low-side) |
| 5 | VS | power_in | Analog power supply pin (range 2.7V to 5.5V) |
| 6 | IN+2 | input | Channel 2 positive current sensing input; connect to bus voltage side of sense resistor (high-side) or load side (low-side) |
| 7 | IN-2 | input | Channel 2 negative current sensing input; connect to load side of sense resistor (high-side) or ground side (low-side) |
| 8 | OUT2 | output | Channel 2 analog output voltage proportional to sensed current magnitude and direction |
| 9 | REF2 | input | Channel 2 reference voltage input (range 0V to VS); sets the zero-current output level for bidirectional current sensing |
| 10 | NC | unconnected | No internal connection; pin may be left floating or connected to any voltage between VS and ground |
| 11 | NC | unconnected | No internal connection; pin may be left floating or connected to any voltage between VS and ground |
| 12 | REF3 | input | Channel 3 reference voltage input (range 0V to VS); sets the zero-current output level for bidirectional current sensing |
| 13 | OUT3 | output | Channel 3 analog output voltage proportional to sensed current magnitude and direction |
| 14 | IN-3 | input | Channel 3 negative current sensing input; connect to load side of sense resistor (high-side) or ground side (low-side) |
| 15 | IN+3 | input | Channel 3 positive current sensing input; connect to bus voltage side of sense resistor (high-side) or load side (low-side) |
| 16 | GND | power_in | Analog ground reference pin |
| 17 | IN+4 | input | Channel 4 positive current sensing input; connect to bus voltage side of sense resistor (high-side) or load side (low-side) |
| 18 | IN-4 | input | Channel 4 negative current sensing input; connect to load side of sense resistor (high-side) or ground side (low-side) |
| 19 | OUT4 | output | Channel 4 analog output voltage proportional to sensed current magnitude and direction |
| 20 | REF4 | input | Channel 4 reference voltage input (range 0V to VS); sets the zero-current output level for bidirectional current sensing |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | TSSOP-20 |
| Category | Amplifiers/Comparators |
| Pins | 20 |

## CAD (KiCad official)

- Symbol: `INA4181A1QPWRQ1`
- Footprint: `Package_SO:TSSOP-20_4.4x6.5mm_P0.65mm`
- 3D model: TSSOP-20 (KiCad packages3D, STEP)
- 3D model files: `ina4181a1qpwrq1-etched.step` / `ina4181a1qpwrq1-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ina4181a1qpwrq1.step` / `ina4181a1qpwrq1.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Texas Instruments datasheet](https://www.ti.com/cn/lit/gpn/ina181-q1) (57 pp, sha256 `4b84b5214b961c3a`, retrieved 2026-10-03, 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-haiku-4-5-20251001` (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/ina4181a1qpwrq1-datasheet.pdf)