Yageo KEMET USEQGCK5000000, User Manual

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TO CO
2
Gas Sensing Evaluation Kit (Analog) USEQGCK5000000
The above information is believed to be correct but does not purport to be all inclusive and must be used only as a guide.
© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard
Fort
Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
15
6.1 Commands Description
Command
Character Code
Description Response
0 Null command
“ok”
1 Get product details Product string
2
Set number of
channels
“Set number of channels (1, 2 or 4
accepted)”
“ok” or “Error setting not accepted”
3 Set Gain
“Send channel number (1, 2, 3 or 4
accepted)”
“Send gain setting (1, 2, 4, 8, 16, 32, 64, 128
accepted)” or “Error setting not accepted”
“ok” or “Error setting not accepted”
4 Set emitter frequency
“Send Frequency (2 to 30 accepted)”
“ok” or “Error setting not accepted”
5 Get MS
1
CH1
“12345”
6 Get MS
1
CH2
“12345” or “Channel not active”
7 Get MS
1
CH3
“12345” or “Channel not active”
8 Get MS
1
CH4
“12345” or “Channel not active”
9
Start streaming raw
data
“ok” then the kit will stream binary data
values
10 Set RMS filter width
“Send filter width (1 to 254 accepted)”
“ok” or “Error setting not accepted”
11 Set duty cycle
“Send duty cycle, 2 = 50%, 4 = 25%”
“ok” or “Error setting not accepted”
12 Get settings
“No channels = x, Gain 1 = x, Gain 2 = x,
Gain 3 = x, Gain 4 = x, RMS filter width = x,
Duty cycle = x%”
13 Reset defaults
“System reset to default”
255 Stop streaming data
“ok”
6.2 Sampling and Signal Processing for KEMET TO Sensors
KEMET
’s unique thin film pyroelectric sensors have excellent response at higher modulation
frequencies than many existing competitor sensors. This higher frequency performance has
the benefit of reducing the impact of pink (1/F) noise that can plague both sensors and
electronics at the low frequencies often used in infrared applications. Good system engineers
will be aware that pink noise may be the dominant noise source when operating at below ~4
Hz. This is in stark contrast to most electronics applications where signals in excess of 1 kHz
are examined, and pink noise is less significant. For many applications, including NDIR gas
sensing and IR spectroscopy, by operating KEMET sensors at higher modulation frequencies
the pink noise can be further suppressed, improving the signal to noise ratio. KEMET sensors
will still outperform
competitors’ sensors in the 1 – 4 Hz operational range in a circuit optimized
for KEMET.
KEMET ITV sensor products provide customers with a combination of class leading S/N and
unparalleled temperature stability, as well as excellent part to part uniformity. These
advantages are brought about by the combination of KEMET
’s advanced MEMs based thin
1
If the MS is to be used for Beer-Lambert calculations it is necessary to take the square root of the MS value returned, as the C8051F 350 doesn’t
calculate the square root, as for example, Result = sqrt ( Get MS CHx )