# CH70120AB5PR

**COSEMITECH** · Current Sensors · SOIC-8

CH70120AB5PR from COSEMITECH, in a SOIC-8. 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 | IP+ | passive | Positive terminal of the internal current-sense copper conduction path (fused with pin 2). Current flowing from IP+ (pins 1,2) into IP− (pins 3,4) yields a positive-slope output. Primary conductor resistance is 0.8 mΩ typical; electrically isolated from the sensor leads by 3000 VRMS. |
| 2 | IP+ | passive | Positive terminal of the internal current-sense copper conduction path (fused with pin 1). Carries the primary current being measured. Primary conductor resistance is 0.8 mΩ typical. |
| 3 | IP- | passive | Negative terminal of the internal current-sense copper conduction path (fused with pin 4). Return terminal for the primary current being measured. Electrically isolated from the low-voltage sensor leads (pins 5-8). |
| 4 | IP- | passive | Negative terminal of the internal current-sense copper conduction path (fused with pin 3). Return terminal for the primary current being measured. |
| 5 | GND | power_in | Signal ground reference for the sensor circuitry and the VIOUT output. |
| 6 | FILTER | passive | External filter-capacitor pin. A capacitor from FILTER to GND forms an RC low-pass with the internal 1.7 kΩ filter resistor to set the output bandwidth and adjust noise/resolution. Typical application uses ~10 nF for a bandwidth reduction, or the pin can be left with the recommended CF value from the electrical table. |
| 7 | VIOUT | output | Analog output voltage proportional to the sensed primary current. For the CH70120AB5 (bidirectional, ratiometric, 5 V supply), VIOUT = VCC/2 at 0 A with sensitivity 100 mV/A over ±20 A. Recommended load ≥4.7 kΩ; output can swing from VOL (≤0.2 V) to VOH (≥VCC−0.2 V). |
| 8 | VCC | power_in | Device power-supply input. Nominal 5 V ±0.5 V for the CH70120AB5 variant (absolute max 6 V). Supply current ICC ≈ 10 mA typical (14 mA max). Decouple with ~0.1 µF to GND close to the pin; VIOUT is ratiometric to this rail. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | COSEMITECH |
| Package | SOIC-8 |
| Category | Sensor |
| Pins | 8 |

## Ordering variants

Same part, different packaging or reel option.

- `CH70120AB5PR`
- `CH70120AB3PR`
- `CH70120BB5PR`
- `CH70120CB3PR`

## CAD (KiCad official)

- Symbol: `CH70120AB5PR`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `ch70120ab5pr-etched.step` / `ch70120ab5pr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ch70120ab5pr.step` / `ch70120ab5pr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [COSEMITECH datasheet](docs/ch70120ab5pr-datasheet.pdf) (62 pp, sha256 `bc54e9c5ff632dd6`, 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/ch70120ab5pr-datasheet.pdf)