1-1
IM 707235-01E
Functions
1
Chapter 1 Functions
1.1
System Configuration and Block Diagram
System Configuration
The following is an example in which the WE7235 4-CH, 100 kS/s Accelerometer Module
is installed into the measuring station and the measuring station is connected to the PC
with the optical fiber cable.
Signal input
DUT
Optical fiber cable
Measuring station
Optical interface
module
WE7235
PC
Optical interface card
Block Diagram
+24V
Programmable
gain amplifier
Acquisition
control
WE bus
interface
WE bus
Module control
program flash
memory
Acquisition
memory
Filter
4mA
AC/DC
CH 1
CH 2
CH 3
CH 4
ATT
PGA
ADC
LPF
AAF
Description of Operation
This module can measure the acceleration signal and voltage received from built-in
amplifier type acceleration sensors.
In acceleration measurement, the module supplies a 4-mA driving current to the built-in
amplifier type acceleration sensor. The output signal from the built-in amplifier type
acceleration sensor is the sum of the DC bias voltage and the AC acceleration signal
voltage. The AC coupling circuit extracts only the acceleration signal component from
the signal and passes the resultant signal to the programmable gain amplifier.
In voltage measurement, the voltage signal applied to each channel goes through the
AC/DC coupling circuit and attenuator (ATT) as necessary. It is, then, passed to the
programmable gain amplifier where the voltage amplitude is adjusted.
Next, the input signal goes through the low-pass filter (LPF) and the anti-aliasing filter
(AAF) and enters to the A/D converter (ADC). In the A/D converter, the input signal is
sampled by synchronizing to the clock provided by the time base and converted to digital
data.
The digital data is then stored in the acquisition memory according to the sampling
interval and the trigger condition settings.
The data in the acquisition memory can be read from the PC.