Super-accurate, low-power temperature sensors comply with I2C and SMBus 3.0

With typical temperature-reading accuracy of 0.25°C and low operating and standby current, the STMicroelectronics STTS22H enhances temperature and heat-flow monitoring in asset trackers, shipping-container loggers, HVAC systems, air humidifiers, refrigerators, building-automation systems, and smart consumer devices.

The STTS22H is I²C and SMBus 3.0 compliant, and supports flexible operating modes including configurable output data rate (ODR) down to 1Hz, a power-saving one-shot mode, and an interrupt pin that supports SMBus Alert Response Address (ARA). This allows the sensor, as an SMBus slave, to signal the application if a user-programmed upper or lower temperature threshold is exceeded. Programmable I²C/SMBus slave addresses allow up to two STTS22H sensors to share the same bus.

Power consumption is very low, drawing just 2.0µA at 1Hz ODR and 1.75µA during periodic one-shot measurements, helping extend the running time of battery-powered devices. In standby mode with the serial port inactive, the STTS22H draws a mere 0.5µA (typical). The 1.5-3.6V operating-voltage range allows use with various power sources such as a small lithium cell.

The sensor is fast-acting, with conversion time of 5ms, and provides 16-bit temperature data. The package features a metal slug that minimizes thermal resistance to ensure fast settling at the ambient temperature. Devices come factory-calibrated and maintain the 0.25°C typical accuracy from -10°C to 60°C, eliminating any need for user calibration.

The STTS22H is in production now as a compact and low-profile 2.0mm x 2.0mm x 0.5mm 6-lead UDFN, priced at $0.49 for orders of 1000 pieces.