Single-chip solution for TPMS: The SMP290 sensor module from Bosch in Rutronik’s automotive portfolio
Rutronik is expanding its automotive portfolio with a compact sensor module from Bosch. The SMP290 is a fully integrated, Bluetooth-enabled single-chip solution for tire pressure monitoring systems (TPMS). The module contains a Bluetooth Low Energy interface, a microcontroller, a MEMS pressure and temperature sensor, a 2-axis MEMS acceleration sensor and a voltage measurement function. Diagnostics and communication are possible in both directions via the standardized BLE 5.4 interface. Measurement data or updates can be encrypted for transmission with the customer-specific application software. As the BLE standard is already used in vehicle components such as infotainment or radio keys, the sensor module fits perfectly into the vehicle’s radio landscape. Together with other Bosch components, the SMP290 is available at www.rutronik24.com.
Tire pressure sensors play a decisive role in the service life of tires, as well as in fuel consumption, ensuring the road safety of vehicles. The SMP290 has a sensor readout ASIC whose core comprises the energy-efficient 32-bit MCU ARC EM6 with FPU, DMA and cache for minimum power consumption. The 64 kB RAM ensures a reliable start. The SMP290 also contains an analog front end for the pressure sensor, temperature measurement via on-chip diode, the x- and z-axis acceleration sensor and battery voltage monitoring.
Features
The module implements an advanced power management system on the ASIC with low-power circuits: configurable and high-efficiency DC/DC converter, low-noise bandgap references, low-drop-out regulator, an HF RC oscillator for efficient MCU operation, an accurate low-frequency RC oscillator for sleep mode control, and a low-power, low-frequency RC oscillator for deep sleep mode control. A coordinated digital control system optimizes power consumption and lifetime of the TPMS sensor. Developers can choose between 0, 4 and 6 dBm transmission power.
The sensor module is available in a 3.5 mm x 4.5 mm DFN housing with Wettable Flanks for automatic optical inspection (AOI). It impresses developers with the low number of external components required and the correspondingly low TCO.
In terms of security, the SMP290 offers a low-power hardware implementation of AES-128 encryption. In addition, it performs a cyclic redundancy check (CRC) of all parameters consumed by the digital signal chain, traceability and stored runtime data.
Benefits and features
- Integrated sensors
- Pressure sensor up to (90 kPa to 920 kPa; 90 kPa to 1500 kPa)
- Acceleration sensor in x- (-330 G to 330 G) and z-direction (-960 G to 960 G)
- Temperature sensor (-40 °C to 125 °C)
- Battery voltage monitoringThermal shutdown
- Power management system:
- Digital step-down DC/DC operation with 1.9 to 3.6 V
- Optional switchable buffer capacitor to support low battery supply at low temperatures
- Low power consumption at 3 V
- High power RF radio
- Operating temperature: -40 °C to +125 °C
Application examples
- Valve-based as well as in-tire TPMS applications
- Compatible with Remote Keyless Entry (RKE) systems
For more information to the SMP290 by Bosch a direct ordering option, please visit our e-commerce platform at www.rutronik24.com