Low-power Piezo Resistive Sensor Signal Interface IC

Its current consumption is extremely low (18.3 μA, one pressure conversion in a second at maximum resolution and including sensor bridge current) and it can operate at low supply voltage from 1.8 V to 3.6 V which makes it an ideal solution for interfacing a piezo-resistive sensor in power consumption critical portable applications.

The effective number of bits of the ADC is 17.4 bits. The over sampling ratio of the delta-sigma-converter has five values to choose from for further optimization between conversion accuracy, speed and current consumption. MAS6503 also features supply voltage monitoring mode which is especially useful in battery operated systems.

The external sensor bridge can be used to sense not only pressure but also temperature, using the built-in sensor sampling switches. The MAS6503 communicates via a standard 2-wire I²C serial bus interface.

Features:

• Low Standby Current Consumption 10 nA Typ,
• Very Low Supply Current: 0.9 ?A…18.3 ?A Typ,
• Supply Voltage: 1.8 V…3.6 V,
• Ratiometric delta-sigma Conversion,
• Selectable Input Signal Ranges (VDD=2.7V): 373, 253, 172 and 115 mV_PP,
• Selectable Optional Offsets (VDD=2.7V): ±126, ±86, ±57 and ±40 mV,
• Selectable Sensor Resistance Values: 2, 2.5, 3, 3.5, 4, 4.5, 5 and 10 kW,
• Over Sampling Ratio: 4096, 2048, 1024, 512 and 256,
• Internal System Clock Signal 250 kHz,
• Conversion Times 1.41 ms…16.77 ms Typ,
• 2-Wire Serial Data Interface (I²C Bus),
• 256 Bit EEPROM Memory,
• Good Noise Performance thanks to the delta-sigma Architecture,
• VDD monitoring mode.

MAS6503 is available in a QFN-16 4x4x0.75 package as well as tested wafer or die in waffle pack. For further information and samples please contact Micro Analog Systems.