Panasonic KX-F910BX Service Manual page 57

Let's observe the wave form to fix the defective IC.
Please observe A0, D0, ROMCE, RD by using digital oscilloscope.
Below graph show you the wave form that is observed when unit
(board) is working correctly. Both graph are good wave. Wave
form is rapidly changing by one (like below graph). Because many
kind of data or program are rapidly executed,
so you can see some kind of wave forms that is seem to below
graph.
CH1
CH2
CH3
CH4
W1
Length
W2
Length
Sampling
Marker 1
T
V
Marker 2
T
V
T
1/ T
47.06kHz
V
Time
Time Base
Internal
CH1
CH2
CH3
CH4
W1
Length
W2
Length
Sampling
Marker 1
T
V
Marker 2
T
V
T
1/ T
V
Time
Time Base
Internal
5V/div
H1 W1
5V/div
5V/div 10.0V A0
5V/div
500ns/div
100
5µs/div
1k
D0
Normal
20Msps
-13.75µs
5.0 V
7.50µs
0.2 V
ROMCS
21.25µs
-4.8 V
RD
-40.0V
7.25µs
Roll
Off
5V/div
H1 W1
5V/div
A0
5V/div 10.0V
5V/div
500ns/div
100
5µs/div
1k
D0
Normal
20Msps
-13.75µs
5.0 V
7.50µs
0.2 V
ROMCS
21.25µs
47.06k Hz
-4.8 V
RD
-40.0V
-17.75µs
Roll
Off
name
A0
D0
ROMCE
RD
SRAMCS:
MDMCS
12.25µs
-12.75µs
| 61 |
KX-F910BX
location
: pin 132 of ASIC (IC1)
: pin 131 of ASIC (IC1)
: pin 22 of ROM (IC2)
: pin 24 of ROM (IC2)
: pin 20 of SRAM(IC3)
: pin 54 of MODEM(IC11)
Time/div
W1 500ns
W2 5µs
Position
W1 7.25µs
W2 25.00µs
Time Base
Internal
External
OK
Time/div
W1 500ns
W2 5µs
Position
W1 -17.75µs
W2 -24.80µs
Time Base
Internal
External
OK