# ADS8505IDWR

**Texas Instruments** · Analog To Digital Converters (ADC) · SOIC-28-300mil

ADS8505IDWR from Texas Instruments, in a SOIC-28-300mil. 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 | VIN | power_in | Analog input with a ±10-V input range (see Figure 28 of the datasheet). |
| 2 | AGND1 | power_in | Analog ground, used internally as the ground reference point. |
| 3 | REF | bidirectional | Reference input/output; requires a 2.2-µF tantalum capacitor to ground. |
| 4 | CAP | passive | Reference buffer capacitor; requires a 2.2-µF tantalum capacitor to ground. |
| 5 | AGND2 | power_in | Analog ground; ground voltage differences between DGND, AGND1 and AGND2 are limited to ±0.3 V. |
| 6 | D15 (MSB) | tri_state | Data bit 15, the most significant bit of the conversion result; high-impedance when CS is high or R/C is low. |
| 7 | D14 | tri_state | Data bit 14; high-impedance when CS is high or R/C is low. |
| 8 | D13 | tri_state | Data bit 13; high-impedance when CS is high or R/C is low. |
| 9 | D12 | tri_state | Data bit 12; high-impedance when CS is high or R/C is low. |
| 10 | D11 | tri_state | Data bit 11; high-impedance when CS is high or R/C is low. |
| 11 | D10 | tri_state | Data bit 10; high-impedance when CS is high or R/C is low. |
| 12 | D9 | tri_state | Data bit 9; high-impedance when CS is high or R/C is low. |
| 13 | D8 | tri_state | Data bit 8; high-impedance when CS is high or R/C is low. |
| 14 | DGND | power_in | Digital ground. |
| 15 | D7 | tri_state | Data bit 7; high-impedance when CS is high or R/C is low. |
| 16 | D6 | tri_state | Data bit 6; high-impedance when CS is high or R/C is low. |
| 17 | D5 | tri_state | Data bit 5; high-impedance when CS is high or R/C is low. |
| 18 | D4 | tri_state | Data bit 4; high-impedance when CS is high or R/C is low. |
| 19 | D3 | tri_state | Data bit 3; high-impedance when CS is high or R/C is low. |
| 20 | D2 | tri_state | Data bit 2; high-impedance when CS is high or R/C is low. |
| 21 | D1 | tri_state | Data bit 1; high-impedance when CS is high or R/C is low. |
| 22 | D0 (LSB) | tri_state | Data bit 0, the least significant bit of the conversion result; high-impedance when CS is high or R/C is low. |
| 23 | BYTE | input | Selects the 8 most significant bits (low) or the 8 least significant bits (high) for output. |
| 24 | R/C | input | With CS low and BUSY high, a falling edge starts a new conversion; with CS low, a rising edge enables the parallel output. |
| 25 | CS | input | Internally ORed with R/C; with R/C low, a falling edge on CS starts a new conversion. |
| 26 | BUSY | output | Goes low at the start of a conversion and stays low until the conversion is complete and the digital outputs are updated. |
| 27 | VANA | power_in | Analog supply input, nominally +5 V; decouple to ground with 0.1-µF ceramic and 10-µF tantalum capacitors. |
| 28 | VDIG | power_in | Digital supply input, nominally +5 V; connect directly to pin 27 and keep it at or below VANA. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOIC-28-300mil |
| Category | Data Acquisition |
| Pins | 28 |

## CAD (KiCad official)

- Symbol: `ADS8505IDWR`
- Footprint: `Package_SO:SOIC-28W_7.5x17.9mm_P1.27mm`
- 3D model: SOIC-28-300mil (KiCad packages3D, STEP)
- 3D model files: `ads8505idwr-etched.step` / `ads8505idwr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ads8505idwr.step` / `ads8505idwr.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/ads8505) (29 pp, sha256 `2dd1a92c2d7ac740`, 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/ads8505idwr-datasheet.pdf)