# INA155E

**Texas Instruments** · Instrumentation Amplifiers · VSSOP-8

INA155E from Texas Instruments, in a VSSOP-8. 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 | RG | passive | Gain-setting pin: leave open for G = 10, connect directly to pin 8 for G = 50, or place a resistor between pins 1 and 8 for 10 < G < 50, keeping the pin 1 to pin 8 connection low impedance (20Ω can cause a 0.2% gain error shift). |
| 2 | VIN- | power_in | Inverting signal input, with a safe input voltage of (V-) - 0.5V to (V+) + 0.5V and an input bias current return path required; inputs beyond the supply rails by more than 500mV should be limited to 10mA. |
| 3 | VIN+ | power_in | Non-inverting signal input, with common-mode range of 0.3V to 5.2V at VS = 5.5V and 0.2V to 2.5V at VS = 2.7V, and an input bias current return path required. |
| 4 | V- | power_in | Negative power supply terminal (ground in single-supply operation), with the device specified for a total supply of +2.7V to +5.5V. |
| 5 | Ref | input | Output reference terminal normally set to VS/2 that must be driven low impedance for good CMRR, since 200Ω in series with Ref degrades a typical device to about 80dB CMRR. |
| 6 | VOUT | output | Output referred to the Ref terminal, swinging to within 10mV of either rail with RL = 10kΩ and rated for ±50mA short-circuit current to ground. |
| 7 | V+ | power_in | Positive power supply terminal, specified for +2.7V to +5.5V with quiescent current of 1.7mA typical and 2.1mA maximum at 25°C. |
| 8 | RG | passive | Second gain-setting pin, used with pin 1 exactly as described for pin 1: open for G = 10, shorted to pin 1 for G = 50, or joined by a resistor for intermediate gains. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | VSSOP-8 |
| Category | Amplifiers/Comparators |
| Pins | 8 |

## CAD (KiCad official)

- Symbol: `INA155E`
- Footprint: `Package_SO:VSSOP-8_2.3x2mm_P0.5mm`
- 3D model: VSSOP-8 (KiCad packages3D, STEP)
- 3D model files: `ina155e-etched.step` / `ina155e-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ina155e.step` / `ina155e.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/ina155) (17 pp, sha256 `477f3b4451cfbf8f`, retrieved 2026-10-08, 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/ina155e-datasheet.pdf)