HP 8112A, Operating, Programming And Servicing Manual

Page: 206 / 406

10.3-6 Servicing the Timing and
Slope Generators
The IC is either free running or triggered by the EXT INPUT,
depending on the state of the internal trigger mode latches (data
from LD5 to LD7). The inverse output OUT is passed to the trigger
amplifier (Chapter 10.7) for subsequent output as TRIG OUT.
Normal output OUT, is passed via level shifter Q200 to the delay
generator trigger input.
Connections are also made from the period generator to the Burst
Clock described in chapter 10.6.
Delay Generator
The delay generator, working in TIME mode produces a time-shifted
output identical in rate to its trigger input. The delay time is
dependant on the analog inputs, internal range data, and triggering
mode. See Figure 10.3-2 for an example of signal generation. A delay
time greater than the periodic time will cause ERROR OUT to
become active. Normal output OUT, is passed via level shifter Q220
to the width generator trigger input.
Width Generator
The width generator, working in TIME mode produces an output
of equal repetition rate to its trigger input, but whose width is
dependant on the analog inputs, internal range data. In DBL mode
the width generator is configured to produce an output pulse at
both leading and trailing edges of the trigger pulse from the delay
generator. See Figure 10.3-2 for an example of signal generation. An
output pulse width which is greater than the periodic time will cause
ERROR OUT to become active. Normal output OUT, is passed
directly to the Slope Generator IC.