HP 8112A, Operating, Programming And Servicing Manual

Page: 222 / 406

___,
-0 . 6 V
1
I
I
I
I
I
I
70ns
r-
\
�
!\_
I
:::::
I
- 1 . B V
�
1 00us
�
Figure 1 0.3-14. Width Generator ramp signal
4.
Check the signal being sent to the slope generator IC at TP3
against Figure
10.3- 15.
-0 . 2V
-0 . B V
DBL MODE
�
2 00us
�
Figure 1 0.3-1 5. Width Generator output
5.
Check the Width Generator operation against Table
10.3- 14
and
Table
10.3- 1 5
Table 1 0.3-14. Width Generator Operation
U240 Pin Mnemonic
5 WIDC
2 ERW
10 WIC
11 to 18 LD7 - LDO
R245
Description State
Width control voltage input
L
Width error output signal L
Width input store select See Table 10 .3-1
Data to be latched into
See Table 10 .3-2
the input store of U240
Width Vernier Current
See Table 10.3-15
6. Verify that voltage at
U240
pins
1, 4
and
5
are at virtual ground
(min.
-40
mV max.
0
V)
1 0.3-20 Servicing the Timing and
Slope Generators