Agilent Technologies 93000 SOC Series Training Manual page 95

Front-End Module
The front-end module consists of two main blocks which fulfil the
tasks of conditioning the signals for the TIA instrument and of
routing the signals to the TIA instruments:
Input Block
•
- signal conditioning
- routing to the center block
- loop-back routing and routing for dc measurements (For details
about these routing types, see "Pin Connections with an Analog
Module's Multiplexer" on page 99)
- input termination (10 kOhm to ground or 50 Ohm with
termination voltage)
Center block (7x4 multiplexer)
•
- routing of input lines (up to 4 of 7) to the TIA instrument(s)
The front-end module performs signal conditioning of the incoming
signals to provide the TIA instruments with signals that allow a
clean edge detection.
+ 6V
0V
-2V
Threshold voltage
Signal Conditioning by the Front-End Module
The conditioned signal is the input to the center block (7x4
multiplexer). The multiplexer is used to select one or two input
pins for each TIA instrument from the seven input pins to the
front-end module.
The center block also contains the comparator for the trigger
signal to detect a signal transition across 0V which triggers (arms)
the TIA.
Lesson 1 – Analog Modules
INPUT SIGNAL
INTPUT SIGNAL
TO
CH1 FRONT-END
OUTPUT SIGNAL
TO
TIA INSTRUMENT
TIA CORE
95