HP 3455A - Page 187

Start
With
A
Display
Reading Of
(3
"
(Test
0
Failure), Mea-
sure
The Switch
Drive
Voltage On
Pin
14
Of
A10U9.
i i
is
Is
The Switch
Drive
Voltage At
Pin
1
Of
A10U4
Approx.
\
QVdc?
^
The Drive
Voltage
Approx.
^
-HO
V
dc?
YES
YES
NO
NO
Is
Is
Is
Is
The
Driver
Input
Voltage At
Pin
9
Of
A10U9 >
4
V dc
YESYES
The
Voltage
At
A10TP8
-I-
10 V
do?
Check
A10U9 And Associ-
ated Components.
The
Driver Input
Voltage
At
Pin
7
Of
A10U4 >
4
V
dc
'^The Voltage^
At A10TP1
Approx.
0
V
dc
YES
YES
Check A10U4
And
Associ-
ated
Components.
?
?
NO
NO NO
NO
Troubleshoot
The
Attenu-
ator Circuit
(A10U18,
Q35, Q37, Q38,
Q39
,
040
And Associated Com-
ponents).
Troubleshoot
The Refer-
ence Supply (All
Assem-
bly A10U7
and Associ-
ated
Components).
Is
Is
Troubleshoot The
Logic
Circuit (A10U13, U22,
U26
And Associated
Com-
ponents).
The Device Select
Signal
At
Pin
9
Of
A10U13 >
4 V
Peak -To
-Peak
.
Troubleshoot
The
Logic
Circuit
(A10U13,
U22,
U26
And Associated
Com-
ponents).
YES
The
Device Select
Signal
At
Pin
9
Of
A10U13 >4 V
^
Peak -To
-Peak
YES
?
NO
NO
Troubleshoot
The Device
Select
Circuit
(A10U13,
U14, U26 And
Associated
Components).
Troubleshoot The
Device
Select Circuit
(A10U13,
U14,
U26
And
Associated
Components)
.
3455-D-IO
Is
Is
H
he Switch
Driv?^
Voltage
At
Pin
1
Of
A10U6
Approx.
+
1
V dc?
(Ignore
s.
The
2
Msec
^
pulse)
''^The
Switch
Drived
Voltage At
Pin 14 Of
A1
0U5
Approx.
+
1 V dc?
(Ignore
s.
The
2
msec
pulse)
Check
Switching
FET's
A10Q16,
021, 029,
031
,
032,
038
And
Associ-
ated
Components.
YES
YES
NO
NO
Is
Is
Is
Is
The Gate
Bias
^
Voltage
At
A10TP3
Approx.
+
1
V
dc?
(Ignore
The
2
msec
"X. pulse)
The
Gate
Bias
Voltage
At
A10TP3
Approx.
+
1 V dc?
(Ignore
The
2
msec
X. Pulse)
^
The
Driver
Input
Voltage
At
Pin
9
Of
A10U5
>
4 V dc
The Driver Input
Voltage
At
Pin
7
Of
A10U6 >
4
V
dc
Y
YES
YES
Check
A10U6
And
Associ-
ated
Components.
Check A10U5
And Associ-
ated
Components.
?
?
NO
NO
NO
NO
Troubleshoot The
Gate
Bias
Amplifier Circuit
(A10U1,
05
And Associ-
ated Components).
Troubleshoot
The
Gate
Bias
Amplifier
Circuit
(A10U1, 05
And Associ-
ated
Components).
Is
Is
Troubleshoot
The
Logic
Circuit (A10U16, U22,
U26
And Associated Com-
ponents).
The Device
Select
Signal At
Pin
9
Of
A10U16 >
4
V
Peak
-To
-Peak
Troubleshoot
The Logic
Circuit (A10U16, U22,
U26
And Associated
Com-
ponents).
YES
The
Device Select
Signal
At
Pin
9 Of
A10U16 > 4
V
^
Peak
-To
-Peak
.
YES
?
7
NO
NO
Troubleshoot
The
Device
Select
Circuit
(A10U16,
U14,
U26
And
Associ-
ated
Components).
Troubleshoot
The Device
Select Circuit
(A10U16,
U14,
U26
And Associ-
ated
Components).
Figure 8-H-16.
Inguard Troubleshooting
Procedure Diagram,
Auto-Cal Circuitry TEST 0.
8-109/8-110