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Quartz Transducer Counting Interface AVA-07
22-Apr-2015
Page 6 of 7
I²C Command
Read from EEPROM
Write to EEPROM
Condition
Always
Write protection cleared through
control byte access
Write protection is not cleared
Result
EEPROM data is returned
Data is written to EEPROM
Data is not written to EEPROM
Due to the I²C restrictions described above, it is not possible to guarantee that the AVA-07
will by default work with any acquisition system that works with Digital Quartzdyne
Transducers.
However, the AVA-07 has been tested to work with the AVA-03 Digital Quartzdyne
Tester and also with Quartzdyne's Q-Link interface, and generally should work with any
equipment that generates alternating pressure and temperature queries.
If in doubt, please contact Avanti for guidance.
Note that a complete 4-channel Frequency Transducer to Q-Link interface (Model No.
AVA-08) is also available, which includes 3V to 5V step up circuitry to support legacy
transducers.
5. RESOLUTION
The resolution of the pressure / temperature measurement depends on the gate time used
by the internal counters. Depending on the MODE link, the gate time is either fixed at 1sec
or self-adjusting between 91ms and 2.8sec according to the I²C query rate. The table below
summarises the resolution that can be expected for a number of different gate times.
Gate Time
0.091 sec
0.182 sec
0.273 sec
0.364 sec
0.455 sec
1.001 sec
1.456 sec
2.002 sec
2.821 sec
Table 2: Resolution versus Gate Time
Typical
Worst case
Typical
frequency
frequency
pressure
resolution (at
resolution (at
resolution of
50kHz)
70kHz)
10k transducer
(2.7Hz per psi)
Typical
pressure
resolution of
16k transducer
(2.4Hz per psi)
0.1526 Hz
0.0763 Hz
0.0509 Hz
0.0382 Hz
0.0305 Hz
0.0139 Hz
0.0095 Hz
0.0069 Hz
0.0049 Hz
0.0636 psi
0.0318 psi
0.0212 psi
0.0159 psi
0.0127 psi
0.0058 psi
0.0040 psi
0.0029 psi
0.0021 psi
0.2137 Hz
0.1068 Hz
0.0712 Hz
0.0534 Hz
0.0427 Hz
0.0194 Hz
0.0134 Hz
0.0097 Hz
0.0069 Hz
0.0565 psi
0.0283 psi
0.0188 psi
0.0141 psi
0.0113 psi
0.0051 psi
0.0035 psi
0.0026 psi
0.0018 psi
© Avanti Elektronik Limited - (44) 01224-583132 - www.avanti.clara.net - [email protected]
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