Digital Section - Agilent Technologies 4263B LCR Service Manual

In the gure, the transformer primary is connected to H
secondary is connected to the H
common.
When measuring the turns ratio, for example, the 4263B measures the primary voltage and
secondary voltage while applying an ac voltage to the primary. The 4263B calculates the turns
ratio from the ratio of these two voltages. For primary voltage measurement, SW1 switches to
H , and for secondary voltage measurement, SW1 switches to H
CUR
obtained in a similar manner.

Digital Section

Figure 4-8 shows the Digital Section block diagram.
The digital section consists of the A2 CPU Board Assembly and other peripheral assemblies
such as the keyboard and LCD. The section communicates with the A1 Main Board Assembly in
order to control the latches, switches, and other components on the A1 assembly and receive
the measurement data. The GPIB interface on the A2 Assembly allows the 4263B communicate
with a controller. A handler interface on the A1 Assembly allows the 4263B communicate with
an external handler.
The A2 CPU Board Assembly includes a processor, ROM, EEPROM, jumpers, switches, and
LEDs.
ROM (A2U11) stores the rmware which controls all the 4263B's operation and functions. The
ROM is mounted in a socket for easy replacement.
and L connectors. L
POT POT
and L connectors, and the
CUR CUR
and L are connected as a
CUR POT
. Other parameters are
POT
T roubleshooting 4-9