# ESP8684H2X

**Espressif Systems** · RF and Wireless · QFN-24-1EP_4x4mm_P0.5mm_EP2.8x2.8mm

ESP8684H2X from Espressif Systems, in a QFN-24-1EP_4x4mm_P0.5mm_EP2.8x2.8mm. 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 | ANT | bidirectional | RF input and output pin for the antenna. |
| 2 | VDDA3P3 | power_in | Analog power domain supply input. |
| 3 | VDDA3P3 | power_in | Analog power domain supply input. |
| 4 | GPIO0 | bidirectional | IO pin powered by VDD3P3_RTC with ADC1_CH0 analog function and default drive strength of 20 mA. |
| 5 | GPIO1 | bidirectional | IO pin powered by VDD3P3_RTC with ADC1_CH1 analog function and default drive strength of 20 mA. |
| 6 | GPIO2 | bidirectional | IO pin powered by VDD3P3_RTC with input enabled at reset and ADC1_CH2 analog function; FSPIQ is available on function F2. |
| 7 | CHIP_EN | input | High enables the chip (powered up) and low disables it (powered down); do not leave this pin floating. |
| 8 | GPIO3 | bidirectional | IO pin powered by VDD3P3_RTC with input enabled at reset and ADC1_CH3 analog function. |
| 9 | MTMS | bidirectional | JTAG test mode select, powered by VDD3P3_RTC, with ADC1_CH4 analog function on GPIO4. |
| 10 | MTDI | bidirectional | JTAG test data input, powered by VDD3P3_RTC. |
| 11 | VDD3P3_RTC | power_in | Power input for the RTC and part of the digital power domains. |
| 12 | MTCK | bidirectional | JTAG test clock, powered by VDD3P3_CPU. |
| 13 | MTDO | bidirectional | JTAG test data output, powered by VDD3P3_CPU. |
| 14 | GPIO8 | bidirectional | IO pin powered by VDD3P3_CPU with input enabled at reset. |
| 15 | GPIO9 | bidirectional | IO pin powered by VDD3P3_CPU with input enabled and internal weak pull-up enabled after reset. |
| 16 | GPIO10 | bidirectional | IO pin powered by VDD3P3_CPU; FSPICS0 is available on function F2. |
| 17 | VDD3P3_CPU | power_in | Power input for the digital power domain. |
| 18 | GPIO18 | bidirectional | IO pin powered by VDD3P3_CPU. |
| 19 | U0RXD | bidirectional | UART0 receive data pin, powered by VDD3P3_CPU with input enabled and weak pull-up enabled after reset. |
| 20 | U0TXD | bidirectional | UART0 transmit data pin, powered by VDD3P3_CPU with output enabled and weak pull-up enabled after reset. |
| 21 | VDDA | power_in | Analog power domain supply input. |
| 22 | XTAL_N | passive | External clock input/output connected to the crystal or oscillator (negative side of differential clock). |
| 23 | XTAL_P | passive | External clock input/output connected to the crystal or oscillator (positive side of differential clock). |
| 24 | VDDA | power_in | Analog power domain supply input. |
| 25 | GND | power_in | External ground connection. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Espressif Systems |
| Package | QFN-24-1EP_4x4mm_P0.5mm_EP2.8x2.8mm |
| Category | RF and Wireless |
| Pins | 25 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Input power pins: allowed input voltage |  | -0.3 |  | 3.6 | V |  | 43 |
| Cumulative IO output current |  |  |  | 730 | mA |  | 43 |
| Storage temperature | TSTORE | -40 |  | 150 | °C |  | 43 |
| Recommended input voltage (VDDA3P3, VDDA, VDD3P3_RTC, VDD3P3_CPU) |  | 3 | 3.3 | 3.6 | V |  | 43 |
| Cumulative input current |  | 0.5 |  |  | A |  | 43 |
| Ambient temperature | TA | -40 |  | 105 | °C |  | 43 |
| High-level input current | IIH |  |  | 50 | nA |  | 42 |
| Low-level input current | IIL |  |  | 50 | nA |  | 42 |
| Differential nonlinearity (ADC connected to an external 100 nF capacitor) | DNL | -1 |  | 3 | LSB | ADC connected to an external 100 nF capacitor; DC signal input; ambient temperature at 25 °C; Wi-Fi off | 43 |
| Integral nonlinearity (ADC connected to an external 100 nF capacitor) | INL | -4 |  | 8 | LSB | ADC connected to an external 100 nF capacitor; DC signal input; ambient temperature at 25 °C; Wi-Fi off | 43 |
| Sampling rate |  |  |  | 100 | kSPS |  | 43 |
| Total error, ATTEN0 |  | -5 |  | 5 | mV | effective measurement range of 0 ~ 950 | 43 |
| Total error, ATTEN3 |  | -10 |  | 10 | mV | effective measurement range of 0 ~ 2800 | 43 |

## CAD (KiCad official)

- Symbol: `ESP8684H2X`
- Footprint: `Package_DFN_QFN:QFN-24-1EP_4x4mm_P0.5mm_EP2.8x2.8mm`
- 3D model: QFN-24-1EP_4x4mm_P0.5mm_EP2.8x2.8mm (KiCad packages3D, STEP)
- 3D model files: `esp8684h2x-etched.step` / `esp8684h2x-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `esp8684h2x.step` / `esp8684h2x.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Espressif Systems datasheet](https://www.espressif.com/sites/default/files/documentation/esp8684_datasheet_en.pdf) (60 pp, sha256 `5d5e6894fbcd9ab5`, retrieved 2026-10-29, tier: manufacturer)
- **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/esp8684h2x-datasheet.pdf)