说明The MAX1457 is a highly integrated analog-sensor signal processor optimized for piezoresistive sensor calibration and compensation. It includes a programmable current source for sensor excitation, a 3-bit programmable-gain amplifier (PGA), a 12-bit ADC, five 16-bit DACs, and an uncommitted op amp. Achieving a total error factor within 0.1% of the sensor's repeatability errors, the MAX1457 compensates offset, full-span output (FSO), offset TC, FSO TC, and full-span output nonlinearity of silicon piezoresistive sensors.
The MAX1457 calibrates and compensates first-order temperature errors by adjusting the offset and span of the input signal via digital-to-analog converters (DACs), thereby eliminating quantization noise. If needed, residual higher-order errors are then compensated using linear interpolation of the first-order coefficients stored in a look-up table (in external EEPROM).
The MAX1457 integrates three traditional sensor-manufacturing operations into one automated process:
- Pretest: Data acquisition of sensor performance under the control of a host test computer.
- Calibration and Compensation: Computation and storage (in an external EEPROM) of calibration and compensation coefficients determined from transducer pretest data.
- Final Test: Verification of transducer calibration and compensation, without removal from a pretest socket.
Although optimized for use with piezoresistive sensors, the MAX1457 may also be used with other resistive sensor types (i.e., accelerometers and strain gauges) with the addition of a few external components.
- High Accuracy (within ±0.1% of sensor's repeatable errors)
- Compensates Offset, Offset TC, FSO, FSO TC, Temperature/Pressure Nonlinearity
- Rail-to-Rail Analog Output for Calibrated, Temperature-Compensated Pressure Measurements
- Programmable Sensor Excitation Current
- SPI/MICROWIRE-Compatible Serial Interface
- Fast Signal-Path Settling Time (< 1ms)
- Accepts Sensor Outputs from 5mV/V to 30mV/V
- Pin-Compatible with MCA7707
- Complete Biometric Sensor Hub
- World-Class Algorithm for Wearable Applications
- High Accuracy
- Long Battery Life
- Small Size
- 1-Wire Interface Requires Only One Port Pin for Communication
- Unique 64-bit Serial Code Stored in an On-Board ROM
- External Resistor Selects Address for Location Identification
- 微小、3.5mm x 7.0mm x 1.5mm、14引脚光模块