# ADR421ARZ

**Analog Devices** · Voltage References · SOIC-8

ADR421ARZ from Analog Devices, in a SOIC-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 | TP | passive | Test pin reserved for factory testing; users should not connect anything to it or the device may not function properly. |
| 2 | VIN | power_in | Input voltage; ADR421 operating range is 4.5 V to 18 V, with 18 V absolute maximum supply voltage. |
| 3 | NIC | unconnected | No internal connection. |
| 4 | GND | power_in | Ground pin, 0 V. |
| 5 | TRIM | passive | Trim terminal that adjusts the output voltage over a ±0.5% range without affecting the temperature coefficient. |
| 6 | VOUT | power_out | Output voltage (2.50 V for ADR421), guaranteed to deliver load currents up to 10 mA. |
| 7 | NIC | unconnected | No internal connection. |
| 8 | TP | passive | Test pin reserved for factory testing; users should not connect anything to it or the device may not function properly. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Analog Devices |
| Package | SOIC-8 |
| Category | Power Management ICs |
| Pins | 8 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output Voltage A Grade | VOUT | 2.497 | 2.5 | 2.503 | V | VIN = 5.0 V to 15.0 V, TA = 25°C | 5 |
| Initial Accuracy A Grade | VOUTERR | -3 |  | 3 | mV | VIN = 5.0 V to 15.0 V, TA = 25°C | 5 |
| Initial Accuracy A Grade | VOUTERR | -0.12 |  | 0.12 | % | VIN = 5.0 V to 15.0 V, TA = 25°C | 5 |
| Temperature Coefficient A Grade | TCVOUT |  | 2 | 10 | ppm/°C | -40°C < TA < +125°C | 5 |
| Supply Voltage Headroom | VIN − VOUT | 2 |  |  | V |  | 5 |
| Line Regulation | ΔVOUT/ΔVIN |  | 10 | 35 | ppm/V | VIN = 5 V to 18 V, -40°C < TA < +125°C | 5 |
| Load Regulation | ΔVOUT/ΔIL |  |  | 70 | ppm/mA | IL = 0 mA to 10 mA, -40°C < TA < +125°C | 5 |
| Quiescent Current | IIN |  | 390 | 500 | µA | No load | 5 |
| Quiescent Current | IIN |  |  | 600 | µA | -40°C < TA < +125°C | 5 |
| Voltage Noise | eN p-p |  | 1.75 |  | µV p-p | 0.1 Hz to 10 Hz | 5 |
| Voltage Noise Density | eN |  | 80 |  | nV/√Hz | 1 kHz | 5 |
| Turn-On Settling Time | tR |  | 10 |  | µs |  | 5 |
| Long-Term Stability | ΔVOUT |  | 50 |  | ppm | 1000 hours | 5 |
| Output Voltage Hysteresis | VOUT_HYS |  | 40 |  | ppm |  | 5 |
| Ripple Rejection Ratio | RRR |  | -75 |  | dB | fIN = 1 kHz | 5 |
| Short Circuit to GND | ISC |  | 27 |  | mA |  | 5 |
| Supply Voltage (operating) | VIN | 4.5 |  | 18 | V | Features list: ADR421 operating range | 1 |
| Supply Voltage |  |  |  | 18 | V |  | 8 |
| Storage Temperature Range |  | -65 |  | 150 | °C |  | 8 |
| Operating Temperature Range |  | -40 |  | 125 | °C |  | 8 |
| Junction Temperature Range |  | -65 |  | 150 | °C |  | 8 |
| Lead Temperature (Soldering, 60 sec) |  |  |  | 300 | °C | Soldering, 60 sec | 8 |
| Thermal Resistance Junction-to-Ambient, 8-Lead SOIC (R) | θJA |  | 130 |  | °C/W | 8-Lead SOIC (R) | 8 |
| Thermal Resistance Junction-to-Case, 8-Lead SOIC (R) | θJC |  | 43 |  | °C/W | 8-Lead SOIC (R) | 8 |

## CAD (KiCad official)

- Symbol: `ADR421ARZ`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOIC-8 (KiCad packages3D, STEP)
- 3D model files: `adr421arz-etched.step` / `adr421arz-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `adr421arz.step` / `adr421arz.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Analog Devices datasheet](https://www.analog.com/media/en/technical-documentation/data-sheets/ADR420_421_423_425.pdf) (24 pp, sha256 `a3f954c509a578f6`, retrieved 2026-10-30, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/adr421arz-datasheet.pdf)