Table of Contents
Advertisement
Analyzer Functional Group
Each functional group consists of one or more assemblies that perform one of the basic
instrument functions. hese groups are the power supply, digital control, source, and receiver.
Power Supply Theory
he power supply group consists of the A6 power supply assembly. his switching power
supply provides regulated DC voltages to power all assemblies in the analyzer through a
connection to the backplane. he backplane serves as a motherboard to provide power, data,
and control signal connections to the various assemblies.
A voltage selector switch, accessible at the rear panel, adapts the analyzer to local line voltages
of approximately 115 V or 220 V nominal. Refer to \Installing the Analyzer" in your analyzer's
ser's Guide
for line voltage tolerances and other power considerations.
he power supply has a standby state instead of an o state when the AC power is connected.
In standby, the A6 assembly provides a standby supply, measuring between +12 V and
+13 V, to power the non-volatile SRAM on the CPU board. (A battery provides power to the
non-volatile SRAM when the instrument is disconnected from AC power.) he power supply
switches on when the on/standby switch is grounded. In the on state, the power supply
provides the following supplies to the instrument: +5 V, +15 V,
wo diagnostic LEDs are visible from the rear panel. he green LED is on in normal operation.
It is o when the line power is absent or set too low, or if the line fuse has blown. he red
LED is on in standby but o during normal operation. It will blink to indicate a power supply
shutdown. Refer to the \ roubleshooting and Block Diagrams" chapter for more details.
Digital Control Theory
his group includes the A1 front panel, A2 CPU, A7 display, and A8 3.5" internal disk drive
assemblies.
A1 Front Panel Assembly
he A1 front panel assembly allows the user to control the analyzer. It includes a keyboard and
a front panel knob (RPG). A probe power jack that supplies +15 V and
use with RF probes and other accessories. Fuses for these supplies are on the back of the A1
front panel assembly PC board.
A2 CPU Assembly
he A2 CPU assembly provides most of the control, interface, and data processing functions
in the analyzer. It contains several microprocessors and many di erent types of memory, as
shown on the analyzer's overall block diagram.
he main CPU is an MC 68030 microprocessor which is augmented by a
oating point
coprocessor (68882). It is the master controller for the analyzer, including the other dedicated
processors on the CPU assembly. When the analyzer is the system controller in an HP-IB
system, it also controls peripheral devices through the HP-IB interface.
he MS 320C32 digital signal processor (DSP) receives the digital data from the A5 receiver
assembly and performs data processing functions such as digital ltering, averaging, and
applying error correction. It has some dedicated SRAM for running its rmware, and it also
uses some shared DRAM and SRAM which is used to transfer data with the CPU.
he MS 34010 graphics system processor (GSP) is responsible for converting data from the
CPU into video signals to drive the A7 display assembly. It also produces an external video
output which is accessible from the rear panel and is VGA compatible.
6-2
Theory of Operat on
0
15 V, and +12 V.
0
12.6 V is available for
Advertisement
Table of Contents
