HP 8112A Operating, Programming And Servicing Manual page 222

1 0.3-20 Servicing the Timing and
Slope Generators
-0 . 6 V
- 1 . B V
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 . 2 V
-0 . B V
�
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
6. Verify that voltage at U240 pins 1, 4 and 5 are at virtual ground
(min. -40 mV max. 0 V)
r-
___,
70ns
!\_
1
I
\
I
I
I
:::: :
I I
�
I
I
� �
1 00us
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Description
Width control voltage input
Width error output signal
Width input store select
Data to be latched into
the input store of U240
Width Vernier Current
DBL MODE
State
L
L
See Table 10 .3-1
See Table 10 .3-2
See Table 10.3-15