Pressure Sensor control IC(Detector×2ch, First order temperature compensation, Two-wire I/F)

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The AK8999A is a piezoresistive semiconductor pressure sensor control IC that compensates temperature drifts and sensor variations. Variations in the sensor can be corrected with compensation values stored in an integrated non-volatile memory (EEPROM). 
The primary characteristics and its associated temperature drifts of pressure sensors are corrected with the 1st order coefficient for temperature compensation or the quasi 2nd order coefficient for temperature compensation by piecewise linear approximation (1st order independent coefficients can be set for high and low temperature side on the basis of 25℃) by integrated temperature compensation circuits for offset voltage and span voltage.
The AK8999A integrates two pressure threshold detectors. When a pressure exceeds the detection threshold stored in the EEPROM is applied, the DET1 and the DET2/PTH pins output “H” or “L” (the output polarity is selectable). This output can be used as a control signal of pressure switch applications.
Accessing to the AK8999A is made via the 2-wire serial interface on CSCLK pin and VOUT pin (set as digital I/O mode) for setting functions and storing compensation values.

Key Features

• Pressure sensor compensation and excitation IC (Analog output)
• Supply voltage current: 8.5mA max @ 8.33kHz sampling
• Supply voltage: 3.0V ± 10%, 3.3V ± 10%, 5.0V ± 10%
• Operating temperature range: -40 to 105 ℃
• Integrated sensor output compensation (AK8999A Input conversion)
    - Offset voltage adjustment
        Adjustment range : Coarse ±13 to ±373mV, Fine ±1 to ±34mV @VDD:5.0V
        Adjustment step  : Coarse 2 to 53mV /step, Fine 0.01 to 0.27mV /step @ VDD:5.0V
    - Offset voltage temperature drift adjustment
      (1st order or Quasi 2nd order correction by piecewise linear approximation)
        Adjustment range : ±0.04 to ±1.23mV/℃ @ VDD:5.0V
        Adjustment step  : 0.2 to 4.8μV/℃ @ VDD:5.0V
    - Output span voltage adjustment (G1, G2, G3)
        Total adjustment range: 3.4 to 261.6mV @ VDD:5.0V
        G1 adjustment step: 0.57 to 74.7mV /step @ VDD:5.0V
        G2 adjustment step: 3.43 to 130.8mV /step @ VDD:5.0V
        G3 adjustment step: 0.01 to 0.40mV /step @ VDD:5.0V
    - Sensitivity temperature drift adjustment
      (1st order or Quasi 2nd order correction by piecewise linear approximation)
        Adjustment range : -4000ppm/ ℃ to 2500ppm/ ℃
        Adjustment step  : 18ppm/ ℃ /step
• Integrated output reference voltage adjustment function
        Adjustment range : 0.02*VDD to 0.98*VDD
        Adjustment step  : 0.002*VDD /step
• Integrated sampling frequency switching function
                       : 0.83kHz, 8.33kHz
• Integrated analog circuit reference voltage stabilizer
• SCF and SMF included for band limitation
                       : fc = 1.0kHz, 500Hz, 250 Hz
• 2-wire serial interface (CSCLK, VOUT pin)
• Ratiometric voltage output
• Integrated constant voltage source for pressure sensor
                       : 2.2V @ VDD:3.0, 3.3V ± 10%, 4.0V or 2.2V @ VDD:5.0V ± 10%
• Integrated pressure threshold detectors (x2)
    - Detection threshold adjustment control
        Adjustment range : 0.125*VDD to 0.9*VDD
        Adjustment step  : 0.025*VDD /step
    - Detection threshold external setting function (DET2/PTH pin use)
    - Hysteresis voltage adjustment control
        Adjustment range : 0.03*VDD to 0.06*VDD
        Adjustment step  : 0.01*VDD /step
• Integrated reference voltage & reference current generator
    - VREF voltage adjustment control
        Resolution: 3bits
        Adjustment step: 1% /step
    - VREF current adjustment control
        Resolution: 4bits
        Adjustment step: 2.8% /step typ.
• Temperature sensor (inter    nal or external)
    - Temperature range: -40 to 105 ℃
    - Internal temperature sensor output voltage adjustment control
        Resolution: 6 bits
        Adjustment step: 0.2% /step
    - External temperature sensor output voltage adjustment control
        Resolution: 9 bits (Coarse=3bits, Fine=6bits)
        Adjustment step: Coarse 10% /step, Fine 0.2% /step
    - Integrated external temperature sensor constant current circuit:±50μA typ.
• Integrated oscillator for intermittent operation (1000kHz typ.)
    - Oscillating frequency adjustment control
        Resolution: 4 bits
        Adjustment step: 5% /step typ.
• Integrated EEPROM for compensation values and control data storage
    - Size: 135 bits
    - Endurance: 1,000 times or more
    - Retention time: 10 years or more @Ta: 105℃
• Supply Type: Die (Tray), Wafer, PKG (UQFN16)

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