# INA199

**Texas Instruments** · Current-sense amplifier · SC70-6

Amplifies the voltage across a shunt into a ground-referenced output, in a tiny SC70-6, with a common-mode range of -0.3 to 26 V that works high-side or low-side regardless of the supply. A REF pin sets the zero-current point for bidirectional current, and fixed-gain options (50, 100, 200 V/V) plus low offset make it accurate at small shunt voltages. It runs from a single 2.7 to 5.5 V rail. A small, precise current monitor for compact boards.

## Pinout

| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | REF | input | Reference voltage input, 0 V to V+. Sets the output bias for bidirectional current sensing. |
| 2 | GND | power_in | Device ground. |
| 3 | V+ | power_in | Power supply input, 2.7 V to 26 V. Quiescent current 100 uA max. Bypass with 0.01 uF to 0.1 uF to GND. |
| 4 | IN+ | input | Positive analog input. Connect to the supply side of the external shunt resistor. Common-mode range -0.3 V to 26 V (INA199Ax) or -0.1 V to 26 V (INA199Bx/Cx). |
| 5 | IN- | input | Negative analog input. Connect to the load side of the external shunt resistor. |
| 6 | OUT | output | Analog output voltage. Output = gain (50/100/200 V/V) x differential shunt voltage, biased around REF. |

## Key specifications

| Parameter | Value |
|---|---|
| Type | Current-sense amplifier (voltage output) |
| Common-mode range | -0.3 V to 26 V |
| Gain options | 50 / 100 / 200 V/V |
| Direction | Bidirectional (via REF) |
| Offset | Low (uV-class) |
| Supply | 2.7-5.5 V |
| Package | SC70-6 |

## Ordering variants

Same part, different packaging or reel option.

- `INA199A1DCKR (gain 50)`
- `INA199A2DCKR (gain 100)`
- `INA199A3DCKR (gain 200)`

## CAD (KiCad official)

- Symbol: `Amplifier_Current:INA199xxDCK (KiCad official)`
- Footprint: `Package_TO_SOT_SMD:SOT-363_SC-70-6`
- 3D model: SC70-6 (KiCad packages3D, STEP)
- 3D model files: `ina199-etched.step` / `ina199-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ina199.step` / `ina199.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/lit/ds/symlink/ina199.pdf) (42 pp, sha256 `80b0656c17984904`, retrieved 2026-08-17, tier: manufacturer)
- **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/ina199-datasheet.pdf)