Teledyne BDS-3960 ユーザーズマニュアル

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Note that instrument air at a pressure of 70 to 80 psig is needed to

activate the proper valves.

T he  Model  BDS   3960 Oxygen Analyzer  uses an 8051

m icrocontr ol l er  wi th 32 kB of RAM and 8 kB of  ROM to cont rol signal
processi ng,,   i nput / output,   and  di splay  functi ons  f or  the  analyzer .  Most  of 
t he  processi ng  power   and  deci si on  making  is  done  by  t he  soft war e
r unni ng on t he pocket PC (P PC).   Syst em  power   is  suppli ed  fr om   a
uni versal  power   supply  module  desi gned  to  be  compat ibl e  wi t h  any
i nt er nat ional   power   sour ce. 

The signal processing electronics including the microprocessor,

analog to digital, and digital to analog converters are located on the I/O
board at the bottom of the case. The preamplifier board is mounted on
top of the I/O board. These boards are accessible by sliding the front out.
Figure 2-7 shows a block diagram of the analyzer electronics.

In the presence of oxygen the sensor generates a current. A current

to voltage amplifier converts this current to a voltage which is further
amplified in the second stage amplifier.

 The output from the second stage amplifier is sent to an 12 bit

analog to digital converter that is located in the same chip as the
microprocessor. The amplifier board also reads the ambient temperature