# AZ431AR-ATRE1

**Diodes Incorporated** · Voltage Reference · SOT-89-3

AZ431AR-ATRE1 from Diodes Incorporated, in a SOT-89-3. 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 | REF | input | Reference (feedback) input. Compared internally to the 2.5 V bandgap; when REF exceeds VREF the internal transistor sinks current from cathode to anode. Max reference input current 10 mA absolute, typ input bias 0.7 µA. |
| 2 | CATHODE | passive | Shunt cathode (K). Sinks the regulation current when REF rises above VREF. Operating cathode voltage VREF to 36 V, cathode current 1 mA to 100 mA (absolute max -100 to 150 mA), off-state leakage 0.05 µA typ. |
| 3 | ANODE | passive | Shunt anode (A), the common return for the reference and the shunt transistor. Normally tied to the low side of the regulated node (circuit ground in a standard shunt-regulator topology). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Diodes Incorporated |
| Package | SOT-89-3 |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

- `AZ431AR-ATRE1`
- `AZ431AR-ATRE1R`
- `AZ431AR-ATRE1Z`
- `AZ431AR-ATRE1N`

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Reference Voltage (0.4% grade) | VREF | 2.49 | 2.5 | 2.51 | V | VKA = VREF, IKA = 10mA | 5 |
| Deviation of Reference Voltage Over Full Temperature Range (0 to +70°C) | VREF |  | 4.5 | 8 | mV | VKA = VREF, IKA = 10mA, 0 to +70°C | 5 |
| Deviation of Reference Voltage Over Full Temperature Range (-40 to +85°C) | VREF |  | 4.5 | 10 | mV | VKA = VREF, IKA = 10mA, -40 to +85°C | 5 |
| Deviation of Reference Voltage Over Full Temperature Range (-40 to +125°C) | VREF |  | 4.5 | 16 | mV | VKA = VREF, IKA = 10mA, -40 to +125°C | 5 |
| Ratio of Change in Reference Voltage to Change in Cathode Voltage (10V to VREF) | VREF/VKA |  | -1 | -2.7 | mV/V | IKA = 10mA, VKA = 10V to VREF | 5 |
| Ratio of Change in Reference Voltage to Change in Cathode Voltage (36V to 10V) | VREF/VKA |  | -0.5 | -2 | mV/V | IKA = 10mA, VKA = 36V to 10V | 5 |
| Reference Current | IREF |  | 0.7 | 4 | µA | IKA = 10mA, R1 = 10kΩ, R2 = ∞ | 5 |
| Deviation of Reference Current Over Full Temperature Range | IREF |  | 0.4 | 1.2 | µA | IKA = 10mA, R1 = 10kΩ, R2 = ∞, TA = -40 to +125°C | 5 |
| Minimum Cathode Current for Regulation | IKA(Min) |  | 0.4 | 1 | mA | VKA = VREF | 5 |
| Off-state Cathode Current | IKA(Off) |  | 0.05 | 1 | µA | VKA = 36V, VREF = 0 | 5 |
| Dynamic Impedance | ZKA |  | 0.15 | 0.5 | Ω | VKA = VREF, IKA = 1 to 100mA, f ≤ 1.0kHz | 5 |
| Cathode Voltage (absolute maximum) | VKA |  |  | 40 | V |  | 4 |
| Cathode Current Range (Continuous) | IKA | -100 |  | 150 | mA |  | 4 |
| Reference Input Current Range | IREF |  |  | 10 | mA |  | 4 |
| Power Dissipation (Z, R package) | PD |  |  | 770 | mW | Z, R Package | 4 |
| ESD (Human Body Model) | ESD |  |  | 2000 | V | Human Body Model | 4 |
| Junction Temperature | TJ |  |  | 150 | °C |  | 4 |
| Storage Temperature Range | TSTG | -65 |  | 150 | °C |  | 4 |
| Cathode Voltage (recommended operating) | VKA |  |  | 36 | V |  | 4 |
| Cathode Current | IKA | 1 |  | 100 | mA |  | 4 |
| Operating Ambient Temperature Range | TA | -40 |  | 125 | °C |  | 4 |
| Thermal Resistance (Junction to Ambient), SOT89 | θJA |  | 165 |  | °C/W | Junction to ambient, SOT89, as printed in Absolute Maximum Ratings | 4 |
| Thermal Resistance (Junction to Case), SOT89 | θJC |  | 29.8 |  | °C/W |  | 5 |

## CAD (KiCad official)

- Symbol: `AZ431AR-ATRE1`
- Footprint: `Package_TO_SOT_SMD:SOT-89-3`
- 3D model: SOT-89-3 (KiCad packages3D, STEP)
- 3D model files: `az431ar-atre1-etched.step` / `az431ar-atre1-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `az431ar-atre1.step` / `az431ar-atre1.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`az431ar-atre1.step`](az431ar-atre1.step) | 57 KB | You want the bare part, or you mark your own boards. |
| [`az431ar-atre1-etched.step`](az431ar-atre1-etched.step) | 1.4 MB | You want the part with `AZ431AR-ATRE1` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 403 faces against 42 in the bare model. It
survives export, section views, and rendering in any CAD tool, and it drops straight
into KiCad or Fusion with no extra setup.

## Provenance

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

- **Datasheet:** [Diodes Incorporated datasheet](https://www.diodes.com/assets/Datasheets/AZ431AR-ATRE1.pdf) (19 pp, sha256 `af7f4848d81a3997`, 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/az431ar-atre1-datasheet.pdf)