Integrated humidity sensors typically have a measurement range of 0% to 100%. However, some manufacturers limit the measurement range to 10% to 95% to ensure accuracy. When designing a humidity/temperature testing system powered by a +3.3V low-voltage power supply, the SHT11 or SHT15 sensor can be selected.
These sensors operate at a current of 550μA during the measurement phase, with an average operating current of 28μA (12-bit) or 2μA (8-bit). They default to sleep mode upon power-up, with a power supply current of only 0.3μA (typical). After measurement, they automatically return to sleep mode unless a new command is received, minimizing chip power consumption. Furthermore, they feature low-voltage detection. When the power supply voltage drops below +2.45V ± 0.1V, bit 6 of the status register is immediately updated, causing the chip to stop operating, thus providing protection.
