A2TPMI

The PerkinElmer A2TPMI is a versatile infrared thermopile sensor with an integrated configurable ASIC for signal processing and ambient temperature compensation. This integrated infrared module senses the thermal radiation emitted by objects and converts this to a analog voltage.

The A2TPMI can be delivered fully factory calibrated and adapted to the customer specification, as well as customer programmable via the serial interface. In the pre-calibrated version, only three pins are necessary for operation: object output voltage, 5V supply voltage, and ground.

As described in this specification, the temperature accuracy of the fully adjustable integrated circuit outperforms that of the previous PerkinElmer thermopile modules with discrete components on pcb, because the A2TPMI features an offset correction of the amplifier and a factory calibrated ambient temperature sensor. This makes the A2TPMI a versatile, compact and high precision device.

Due to the internal digital signal processing and 8 bit resolution of the internal control registers the A2TPMI has improved accuracy for adjustment and improved performance. E²PROM technology allows unlimited changing of the configuration.

For amplification of the highly sensitive thermopile signal in the micro- to millivolt range, a high resolution programmable low noise chopper amplifier is provided. An adjustable high precision ambient temperature sensor followed by a signal processor, offers an accurate compensation signal with polynomial characteristics that perfectly matches to that of the thermopiles output. Adding of these signals results in an ambient independent object temperature signal over a large temperature range, which still can be adapted / scaled to customer needs due to flexible offset and postgain adjustment facilities of the device.

The two configurable comparators of the A2TPMI, that can alternatively be used, enhance the functionality. This allows to employ the A2TPMI as an temperature dependent switch for alarm purposes. Threshold temperatures and the hysteresis is free programmable for both comparators.

Due to integration of sensor and electronic in a compact TO 39 housing, the A2TPMI is robust and insensitive to environmental influences like pcb contamination (leakage currents), humidity and electromagnetic interference.