# LM4040D30QDBZR

**Texas Instruments** · Voltage Reference · SOT-23

LM4040D30QDBZR from Texas Instruments, in a SOT-23. 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 | CATHODE | passive | Parallel current/voltage input; the device regulates the voltage between cathode and anode and needs at least the minimum cathode current IZ,min to regulate, with recommended cathode current up to 15 mA and absolute maximum continuous cathode current of 25 mA. |
| 2 | ANODE | passive | General-purpose pin that is usually grounded, and it forms the other terminal of the shunt reference with the cathode. |
| 3 | * | passive | Must be left floating or connected to the anode; TI recommends connecting it to the anode in applications with high EMI or significant high-frequency switching noise, because a parasitic Schottky diode sits between pins 2 and 3 in the SOT-23 package. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Texas Instruments |
| Package | SOT-23 |
| Category | Power Management (PMIC) |
| Pins | 3 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Reverse breakdown voltage tolerance, 25°C | ΔVZ | -30 |  | 30 | mV | IZ = 100μA, 25°C | 14 |
| Reverse breakdown voltage tolerance, full range | ΔVZ | -75 |  | 75 | mV | IZ = 100μA, full range TA = -40°C to 125°C | 14 |
| Minimum cathode current | IZ,min |  | 47 | 77 | μA | 25°C | 14 |
| Minimum cathode current, full range | IZ,min |  |  | 82 | μA | full range TA = -40°C to 125°C | 14 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -20 |  | 20 | ppm/°C | IZ = 10mA, 25°C | 14 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -15 |  | 15 | ppm/°C | IZ = 1mA, 25°C | 14 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -150 |  | 150 | ppm/°C | full range TA = -40°C to 125°C | 14 |
| Change in reverse breakdown voltage with cathode current | VZ |  | 0.4 | 1.1 | mV | IZ,min < IZ < 1mA, 25°C | 14 |
| Change in reverse breakdown voltage with cathode current | VZ |  |  | 1.3 | mV | IZ,min < IZ < 1mA, full range TA = -40°C to 125°C | 14 |
| Change in reverse breakdown voltage with cathode current | VZ |  | 2.7 | 8 | mV | 1mA < IZ < 15mA, 25°C | 14 |
| Change in reverse breakdown voltage with cathode current | VZ |  |  | 11 | mV | 1mA < IZ < 15mA, full range TA = -40°C to 125°C | 14 |
| Reverse dynamic impedance | ZZ |  | 0.4 | 1.2 | Ω | IZ = 1mA, f = 120Hz, IAC = 0.1IZ, 25°C | 14 |
| Reverse breakdown voltage | VZ |  | 3 |  | V | IZ = 100μA, 25°C | 14 |
| Wideband noise | eN |  | 35 |  | μVRMS | IZ = 100μA, 10Hz ≤ f ≤ 10kHz, 25°C | 14 |
| Long-term stability of reverse breakdown voltage |  |  | 120 |  | ppm | t = 1000 h, TA = 25°C ± 0.1°C, IZ = 100μA | 14 |
| Thermal hysteresis | VHYST |  | 0.08 |  | % | ΔTA = -40°C to 125°C | 14 |
| Continuous cathode current (absolute maximum) | IZ | -10 |  | 25 | mA |  | 5 |
| Operating virtual junction temperature (absolute maximum) | TJ |  |  | 150 | °C |  | 5 |
| Storage temperature range (absolute maximum) | Tstg | -65 |  | 150 | °C |  | 5 |
| Cathode current (recommended operating) | IZ |  |  | 15 | mA |  | 5 |
| Ambient temperature, natural ventilation (recommended operating) | TA | -40 |  | 125 | °C | LM4040xxxQ | 5 |
| Junction-to-ambient thermal resistance, DBZ (3-pin SOT-23) | RθJA |  | 206 |  | °C/W |  | 5 |

## CAD (KiCad official)

- Symbol: `LM4040D30QDBZR`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `lm4040d30qdbzr-etched.step` / `lm4040d30qdbzr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm4040d30qdbzr.step` / `lm4040d30qdbzr.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/lm4040) (62 pp, sha256 `68faec55d71e5cd5`, retrieved 2026-10-08, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **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/lm4040d30qdbzr-datasheet.pdf)