# LM4040C25QDBZR

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

LM4040C25QDBZR 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 | bidirectional | Parallel current/voltage input (cathode); the cathode current IZ must stay within the recommended range of 15 mA maximum and the absolute maximum continuous cathode current of -10 mA to 25 mA. |
| 2 | ANODE | output | General-purpose pin, normally connected to ground; it is the device's reference terminal relative to the cathode. |
| 3 | * | input | Must be left floating or connected to the anode (pin 2); TI recommends tying it to the anode in applications with high EMI or significant high-frequency switching noise, and the datasheet notes a parasitic Schottky diode between pins 2 and 3 on SOT-23. |

## 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 | ΔVZ | -12 |  | 12 | mV | IZ = 100μA; TA = 25°C | 11 |
| Reverse breakdown voltage tolerance | ΔVZ | -38 |  | 38 | mV | IZ = 100μA; TA full range (-40°C to 125°C) | 11 |
| Minimum cathode current | IZ,min |  | 45 | 75 | μA | TA = 25°C | 11 |
| Minimum cathode current | IZ,min |  |  | 80 | μA | TA full range (-40°C to 125°C) | 11 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -20 |  | 20 | ppm/°C | IZ = 10mA; TA = 25°C | 11 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -15 |  | 15 | ppm/°C | IZ = 1mA; TA = 25°C | 11 |
| Average temperature coefficient of reverse breakdown voltage | αVZ | -100 |  | 100 | ppm/°C | TA full range (-40°C to 125°C) | 11 |
| Reverse breakdown voltage change with cathode current | ΔVZ |  | 0.3 | 0.8 | mV | IZ,min < IZ < 1mA; TA = 25°C | 11 |
| Reverse breakdown voltage change with cathode current | ΔVZ |  |  | 1 | mV | IZ,min < IZ < 1mA; TA full range (-40°C to 125°C) | 11 |
| Reverse breakdown voltage change with cathode current | ΔVZ |  | 2.5 | 6 | mV | 1mA < IZ < 15mA; TA = 25°C | 11 |
| Reverse breakdown voltage change with cathode current | ΔVZ |  |  | 8 | mV | 1mA < IZ < 15mA; TA full range (-40°C to 125°C) | 11 |
| Reverse dynamic impedance | ZZ |  | 0.3 | 0.9 | Ω | IZ = 1mA; f = 120Hz; IAC = 0.1IZ; TA = 25°C | 11 |
| Reverse breakdown voltage | VZ |  | 2.5 |  | V | IZ = 100μA; TA = 25°C | 11 |
| Wideband noise | eN |  | 35 |  | μVRMS | IZ = 100μA; 10Hz ≤ f ≤ 10kHz; TA = 25°C | 11 |
| Long-term stability of reverse breakdown voltage |  |  | 120 |  | ppm | t = 1000 h; TA = 25°C ± 0.1°C; IZ = 100μA | 11 |
| Thermal hysteresis | VHYST |  | 0.08 |  | % | ΔTA = -40°C to 125°C | 11 |
| Cathode current (recommended operating) | IZ |  |  | 15 | mA |  | 4 |
| Operating free-air temperature (LM4040xxxQ) | TA | -40 |  | 125 | °C | LM4040xxxQ | 5 |
| 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 |
| Junction-to-ambient thermal resistance | RθJA |  | 206 |  | °C/W | DBZ (3-pin) package | 5 |

## CAD (KiCad official)

- Symbol: `LM4040C25QDBZR`
- Footprint: `Package_TO_SOT_SMD:SOT-23`
- 3D model: SOT-23 (KiCad packages3D, STEP)
- 3D model files: `lm4040c25qdbzr-etched.step` / `lm4040c25qdbzr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `lm4040c25qdbzr.step` / `lm4040c25qdbzr.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 2026-10-12, 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/lm4040c25qdbzr-datasheet.pdf)