Rohde & Schwarz R&S SMU200A, Руководство по обслуживанию

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R&S SMU200A Instrument Design and Function Description
1007.9845.82 3.7 E-6
Attenuators 3 GHz SATT3 and 6 GHz SATT6
The attenuation switchover is performed by solid state switches to increase the life cycle of the module.
The switches are arranged in a matrix designed to minimize the minimal attenuation.
All module-relevant data such as amendment status, model, module name, etc, as well as module-
internal calibration data is stored in non-volatile form in the module EEPROM.
The attenuator requires a +12 V, +5 V, +3.3 V and –12 V supply.
Attenuators
The electronic attenuators switch attenuation in the range from 0 to 125 dB in 5 dB steps.
Protection against Transients
The modules output and input are protected against transients up to 1 ms and 1 W by biased limiter
diodes. The overload status is reported via interrupt to the controller and indicated on the display.
Module Interface
A bus decoder converts the serial operating data to parallel data and stores them on the module.
Function-related events (overload, level reduction, relay control) are processed in realtime via hardware
control lines and interrupts.
Diagnostics
The diagnostics measurement functions are switched to the central diagnostic line DIAG on the
motherboard by means of an analog multiplexer.
Correction Data Memory
The data memory contains data for module identification, statistics and service, as well as module
attenuation data for the individual attenuators covering the entire frequency range.
High-Power Output (Option for SATT3 and SATT6)
With this option the output signal of the RF output stage can be fed directly to the output by means of
bypass relays with low insertion loss. At lower output levels, the electronic attenuator is used.