The Sensirion SDP600 series of digital differential pressure sensors offer superb performance and are targeted at low-cost high-volume applications. These sensors are for use with air or other non-aggressive gases and deliver accurate and stable results even at very low differential pressures.
The SDP600 series operates from a supply voltage of 3.3V and features a digital 2-wire interface enabling easy direct connection to a suitable microprocessor. The measurement signal is internally linearized and temperature compensated.
The SDP6x1 devices (123-7139 & 123-7142) are optimized for measure mass flow or standard volume flow measurements in a bypass configuration.
The SDP6x6 devices (123-7140 & 123-7143) include a power saving feature which effectively puts the sensors into standby mode between measurements.

Pressure Sensors, Sensirion