OPHIR vega User Manual page 91

permanently, even when the instrument is turned off. (See
section 4.4.2.6.1 on data storage). The digital processor
receives data from the A/D converter and translates it
into a measurement of current in Amps. When used with
thermopile sensors, the data is then processed by a
sophisticated digital filter that speeds up the effective
response time of the sensor and rejects noise. In addition,
the MCU converts data from the fast A/D converter and
translates it into a measurement that can be processed
as necessary. The MCU is also responsible for reading
the keypad, driving the LCD display and communicating
via USB or RS232.
The MCU obtains calibration and capability data from a
memory chip in the plug of the detector sensor and
configures itself accordingly. Recalibration data and
saved settings are also stored in this memory chip.
A single DIN socket is used for communications via USB
or RS232. Only one or other of these communication
options is available at any one time.
Power Supply:
The power supply provides the internal DC supply
voltages for the analog and digital processors, and to the
external sensor detector. It also contains the battery
charging circuit and the AC supply for the backlight. The
power supply circuits consist of high efficiency switch-
mode designs.
EMI Protection:
The digital processor circuit and the whole Vega
instrument are protected by EMI protection component
on all signals that pass in and out of the box. In addition,
EMI protection is added internally to prevent
disturbances to the normal functioning of the instrument.
The instrument meets the requirements of the European
Community with respect to electromagnetic compatibility
and has the "CE" mark.
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