# AZ431BN-ATRE1

**Diodes Incorporated** · Voltage Reference · SOT-23

AZ431BN-ATRE1 from Diodes Incorporated, in a SOT-23. 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 to the internal error amplifier. Compared against the internal 2.5V VREF; drive from the external resistor divider between CATHODE and ANODE to program VKA = VREF(1 + R1/R2). Reference input current typ 0.7 μA (max 4 μA); absolute-max IREF is 10 mA. |
| 2 | CATHODE | passive | Cathode (K) of the shunt regulator; sinks the regulation current IKA from the supply through a series resistor. Operating VKA from VREF up to 36V, IKA 1 mA to 100 mA (absolute max -100 to +150 mA, VKA 40V). Dynamic impedance typ 0.15 Ω. |
| 3 | ANODE | passive | Anode (A) of the shunt regulator; the low-side return, tied to circuit ground (or the bottom of the external feedback divider). All cathode and reference currents return through this pin. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Diodes Incorporated |
| Package | SOT-23 |
| Category | PMIC |
| Pins | 3 |

## Ordering variants

- `AZ431BN-ATRE1AN-ATRE1`
- `AZ431BN-ATRE1`
- `AZ431BN-ATRE1AN-ATRG1`
- `AZ431BN-ATRE1BN-ATRG1`
- `AZ431BN-ATRE1AR-ATRE1`
- `AZ431BN-ATRE1BR-ATRE1`
- `AZ431BN-ATRE1AR-ATRG1`
- `AZ431BN-ATRE1BR-ATRG1`
- `AZ431BN-ATRE1AZ-AE1`
- `AZ431BN-ATRE1AZ-ATRE1`
- `AZ431BN-ATRE1BZ-AE1`
- `AZ431BN-ATRE1BZ-ATRE1`
- `AZ431BN-ATRE1AZ-AG1`
- `AZ431BN-ATRE1AZ-ATRG1`
- `AZ431BN-ATRE1BZ-AG1`
- `AZ431BN-ATRE1BZ-ATRG1`
- `AZ431BN-ATRE1AK-ATRE1`
- `AZ431BN-ATRE1BK-ATRE1`
- `AZ431BN-ATRE1AK-ATRG1`
- `AZ431BN-ATRE1BK-ATRG1`

## 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 (0.8% grade) | VREF | 2.48 | 2.5 | 2.52 | 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 (VKA 10V to VREF) |  |  | -1 | -2.7 | mV/V | IKA = 10mA, VKA = 10V to VREF | 5 |
| Ratio of Change in Reference Voltage to Change in Cathode Voltage (VKA 36V to 10V) |  |  | -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 (recommended operating) | VKA |  |  | 36 | V |  | 4 |
| Cathode Current (recommended operating) | IKA | 1 |  | 100 | mA |  | 4 |
| Operating Ambient Temperature Range | TA | -40 |  | 125 | °C |  | 4 |
| Cathode Voltage (absolute maximum) | VKA |  |  | 40 | V |  | 4 |
| Cathode Current Range (Continuous) | IKA | -100 |  | 150 | mA | Continuous | 4 |
| Reference Input Current Range | IREF |  |  | 10 | mA |  | 4 |
| Power Dissipation (N package, SOT23) | PD |  |  | 370 | mW | N package (SOT23) | 4 |
| Thermal Resistance Junction to Ambient (SOT23) | θJA |  |  | 380 | °C/W | SOT23 | 4 |
| Junction Temperature | TJ |  |  | 150 | °C |  | 4 |
| Storage Temperature Range | TSTG | -65 |  | 150 | °C |  | 4 |
| ESD (Human Body Model) | ESD |  |  | 2000 | V | Human Body Model | 4 |
| Thermal Resistance Junction to Case (SOT23) | θJC |  | 135.48 |  | °C/W | SOT23 | 5 |

## CAD (KiCad official)

- Symbol: `AZ431BN-ATRE1`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `az431bn-atre1-etched.step` / `az431bn-atre1-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `az431bn-atre1.step` / `az431bn-atre1.glb` are the bare package body.

## 3D model downloads

Two STEP files. Same geometry, different body top:

| File | Size | Use it when |
|---|---|---|
| [`az431bn-atre1.step`](az431bn-atre1.step) | 59 KB | You want the bare part, or you mark your own boards. |
| [`az431bn-atre1-etched.step`](az431bn-atre1-etched.step) | 1.7 MB | You want the part with `AZ431BN-ATRE1` already on it. |

The marking in the etched file is real recessed geometry cut into the solid, not a
texture or a decal: 454 faces against 69 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/AZ431BN-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/az431bn-atre1-datasheet.pdf)