BME690 — 4-in-1 Environmental Sensor with AI Gas Scanner

**Source:** [Bosch Sensortec BME690 Datasheet (BST-BME690-DS001-04)](https://wtqihf5e8fsv.adom.cloud/uploads/bme690-cbe9164d81a7c1c4.pdf)
**Manufacturer:** Bosch Sensortec
**Part Number:** BME690
**Document:** BST-BME690-DS001-04 — Rev 1.4, May 2025

## Description

The BME690 is a digital 4-in-1 environmental sensor that combines **temperature**, **humidity**, **pressure**, and **gas sensing with Artificial Intelligence (AI)** in a single robust 3.0 × 3.0 × 0.9 mm³ LGA-8 package. It targets mobile, wearable, and connected applications where size and low power consumption are critical, and — unlike earlier Bosch BME68x parts — it is qualified for use in high-condensation environments.

The integrated gas sensor detects Volatile Organic Compounds (VOCs), Volatile Sulfur Compounds (VSCs), carbon monoxide, hydrogen and other gases. The part shares the gas-scanner function of the BME688 and is supported by the **BME AI-Studio** training tool and the **Bosch Software Environmental Cluster (BSEC)** runtime, which emit higher-level outputs such as Indoor Air Quality (IAQ, 0–500), bVOC-equivalent, CO₂-equivalent, and gas-scan class probabilities.

## Key Specifications

| Parameter | Value |
| --- | --- |
| Sensors Integrated | Temperature, Humidity, Pressure, Gas (AI) |
| Package | LGA-8, 3.0 × 3.0 × 0.9 mm³ |
| Supply Voltage VDD | 1.71 V to 3.6 V (1.8 V typ) |
| Supply Voltage VDDIO | 1.2 V to 3.6 V |
| Sleep Current | 0.11 µA typ |
| Operating Temperature | -40 °C to +85 °C |
| Full Accuracy Temperature | 0 °C to +65 °C |
| Pressure Range | 300 hPa to 1100 hPa |
| Humidity Absolute Accuracy | ±3 % r.H. (20–80 % r.H.) |
| Temperature Absolute Accuracy | ±0.5 °C (0–65 °C) |
| Interfaces | I²C, 4-wire SPI, 3-wire SPI |
| Start-up Time | 2 ms |
| IAQ Output Range | 0 – 500 |
| ESD Protection (HBM) | ±2 kV |

## Features

- 4-in-1 environmental sensor — temperature, humidity, pressure, gas with AI
- AI-trainable gas scanner via BME AI-Studio
- BSEC software library with IAQ, bVOC-eq, CO₂-eq, gas-scan outputs
- Detects VOCs, VSCs (H₂S), CO, H₂ and similar reducing gases
- Robust in high-condensation applications (improvement over BME688)
- Compact 3.0 × 3.0 × 0.9 mm³ LGA-8 package
- Ultra-low sleep current (0.11 µA typ)
- Supply range 1.71 V to 3.6 V, optimized for 1.8 V
- I²C and SPI (3-wire / 4-wire) digital interfaces
- Internal IIR filter for pressure and temperature data
- Operating temperature range -40 °C to +85 °C

## Pin Configuration

| Pin | Name | Type | Description |
| --- | --- | --- | --- |
| 1 | GND | Supply | Ground |
| 2 | CSB | Input | Chip select (I²C: tie to VDDIO; SPI: active-low CS) |
| 3 | SDI | In/Out | Serial data input (I²C: SDA; SPI 4W: SDI; SPI 3W: SDI/SDO) |
| 4 | SCK | Input | Serial clock input (I²C: SCL; SPI: SCK) |
| 5 | SDO | In/Out | Serial data output (SPI 4W: SDO; SPI 3W: DNC; I²C: sets address LSB — GND = default) |
| 6 | VDDIO | Supply | Digital / interface supply (1.2 V – 3.6 V) |
| 7 | GND | Supply | Ground |
| 8 | VDD | Supply | Analog supply (1.71 V – 3.6 V) |

Pin numbering is clockwise in top view (counter-clockwise in bottom view). Pin 1 is marked with a dot on the package top.

## Absolute Maximum Ratings

| Parameter | Condition | Min | Max | Unit |
| --- | --- | --- | --- | --- |
| Voltage at any supply pin | VDD, VDDIO | -0.3 | 4.25 | V |
| Voltage at any interface pin | — | -0.3 | VDDIO + 0.3 | V |
| Storage temperature | ≤ 65 % r.H. | -45 | +85 | °C |
| Pressure | — | 0 | 20 000 | hPa |
| ESD | HBM, any pin | ±2 | — | kV |
| ESD | Machine model | ±200 | — | V |

## Electrical Characteristics

| Parameter | Symbol | Condition | Min | Typ | Max | Unit |
| --- | --- | --- | --- | --- | --- | --- |
| Supply Voltage (Internal) | VDD | Ripple max. 50 mV<sub>pp</sub> | 1.71 | 1.8 | 3.6 | V |
| Supply Voltage (I/O) | VDDIO | — | 1.2 | 1.8 | 3.6 | V |
| Sleep current | IDDSL | VDD = VDDIO = 1.8 V, 25 °C | — | 0.11 | 0.14 | µA |
| Standby current | IDDSB | VDD = VDDIO = 1.8 V, 25 °C | — | 0.22 | 0.31 | µA |
| Current (humidity) | IDDH | VDD = VDDIO = 1.8 V, 25 °C | — | 340 | 450 | µA |
| Current (pressure) | IDDP | VDD = VDDIO = 1.8 V, 25 °C | — | 735 | 750 | µA |
| Current (temperature) | IDDT | VDD = VDDIO = 1.8 V, 25 °C | — | 425 | 450 | µA |
| Start-up time | t<sub>startup</sub> | First comm after VDD > 1.58 V and VDDIO > 0.65 V | — | — | 2 | ms |
| PSRR (DC) | PSRR | Full VDD range | — | ±0.01 / ±5 | — | %r.H./V, Pa/V |
| Standby time accuracy | Δt<sub>standby</sub> | — | — | ±5 | ±25 | % |

The power efficiency, performance and heat dissipation scale with supply voltage. BME690 is optimized for 1.8 V.

## Humidity, Pressure & Temperature Sensor Specs

| Parameter | Symbol | Condition | Min | Typ | Max | Unit |
| --- | --- | --- | --- | --- | --- | --- |
| Humidity — Operating range | — | Temperature | -40 | 25 | 85 | °C |
| Humidity — Operating range | — | Relative humidity | 0 | — | 100 | % r.H. |
| Humidity — Full accuracy | — | Temperature | 0 | — | 65 | °C |
| Humidity — Full accuracy | — | Relative humidity | 10 | — | 90 | % r.H. |
| Humidity — Supply current | IDD,H | 1 Hz forced, T+H meas | — | 2.2 | 2.7 | µA |
| Humidity — Absolute accuracy | A<sub>H</sub> | 20–80 % r.H., 25 °C, incl. hysteresis | — | — | ±3 | % r.H. |
| Pressure — Operating range | TA | Temperature | -40 | 25 | 85 | °C |
| Pressure — Full accuracy range | TA | Temperature | 0 | — | 65 | °C |
| Pressure — Operating range | P | Full accuracy | 300 | — | 1100 | hPa |
| Pressure — Supply current | IDD,LP | 1 Hz, lowest power | — | 3.2 | 4.5 | µA |
| Temperature — Operating range | TA | Operational | -40 | 25 | 85 | °C |
| Temperature — Supply current | IDD,T | 1 Hz, temperature only | — | — | 1.3 | µA |
| Temperature — Absolute accuracy | A<sub>T</sub> | 0–65 °C | — | — | ±0.5 | °C |
| Temperature — Absolute accuracy | A<sub>T</sub> | Other range | — | — | ±1 | °C |

## Communication Interface

The BME690 supports three digital interface modes on a shared pin set:

| Interface | Pins Used | Notes |
| --- | --- | --- |
| I²C | SDA (pin 3), SCL (pin 4); CSB tied to VDDIO; SDO sets address LSB | 100 nF on VDD/VDDIO; 4.7 kΩ pull-ups typ |
| 4-wire SPI | SDI, SDO, SCK, CSB | Separate MOSI/MISO |
| 3-wire SPI | SDI/SDO (shared), SCK, CSB; SDO = DNC | Half-duplex |

## Packages

| Package | Dimensions | Pins |
| --- | --- | --- |
| LGA-8 | 3.0 × 3.0 × 0.9 mm³ | 8 |

Pin 1 marker on top of package. Bottom-side pads are recommended to be solder-mask defined (SMD) or non-solder-mask defined (NSMD) on a 1.50 × 3.00 mm pad-pattern footprint.

## Applications

- Indoor air quality measurement
- Bad breath and spoiled food detection (H₂S / VSCs)
- Leakage or fire detection via unusual gases and smells
- Diaper state detection for baby care
- Early-warning for odors and bad smells
- Wildfire detection
- Handsets, tablets, GPS devices
- Smart watches and connected wearables
- Home appliances and IoT products
- Smart home climate sensors and weather stations
- Asset-tracking and surveillance connected devices
- Sensor networks and sensor nodes
- Gaming peripherals and flying toys

## Software API

The BME690 is supported by two Bosch software components:

- **BME AI-Studio** — PC-side training tool for customizing the gas-scanner classifier to a specific application (sensitivity, selectivity, data rate, power).
- **BSEC (Bosch Software Environmental Cluster)** — runtime library running on the host MCU that consumes raw BME690 readings and produces fused outputs: Indoor Air Quality index (IAQ, 0–500), bVOC-equivalent (ppm), CO₂-equivalent (ppm), and gas-scan class probabilities.

BSEC exposes multiple power-mode profiles so end applications can trade update rate against current consumption.