|
65
|
TROUBLESHOOTING GUIDE
KX-F680BX/KX-F2681BX
Below graph show you the wave form that is observed when SRAM doesn't work. (BUS line at SRAM is intentionally
opened.) Please compare OK (under) to NG (upper). SRAMCS (pin 20 of IC3) signal is coming like clock.
In the case of this wave form SRAM access doesn't work. If soldering, conductance is no problem, we need to replace
SRAM (IC3).
CH1 5V/div
CH2 5V/div
CH3 5V/div
CH4 5V/div
W1 5
µ
s/div
Length 1k
W2 5
µ
s/div
Length 1k
Sampling
Normal
20Msps
Marker 1
T 1372.40
µ
s
V 5.0 V
Marker 2
T 7.50
µ
s
V 0.2 V
T -1364.90
µ
s
1/ T
732.7 Hz
V -4.8 V
W1
5µs
W2
5µs
Position
W1
1347.40µs
W2
25.10µs
Time
Time Base
Roll
Off
Time Base
External
Internal
Internal
Trigger CH1/2 MEM1 MEM2
-40.0V
1347.40
µ
s
1397.40
µ
s
Time/div
10.0V
H1 W1
A0
D0
ROMCS
SRAMCS
NG
Like clock
CH1 5V/div
CH2 5V/div
CH3 5V/div
CH4 5V/div
W1 2
µ
s/div
Length 400
W2 5
µ
s/div
Length 1k
Sampling
Normal
20Msps
Marker 1
T 1372.40
µ
s
V 5.0 V
Marker 2
T 7.50
µ
s
V 5.0 V
T -1364.90
µ
s
1/ T
732.7 Hz
V 0.0 V
W1
2µs
W2
5µs
Position
W1
1362.40µs
W2
25.10µs
Time
Time Base
Roll
Off
Time Base
External
Internal
Internal
-40.0V
1362.40
µ
s
1382.40
µ
s
Time/div
10.0V
H1 W1
A0
D0
ROMCS
SRAMCS
OK
Summary of Contents for KX-F680BX
Page 1: ......
Page 11: ......
Page 106: ......
Page 107: ......
Page 108: ......
Page 109: ......
Page 110: ......
Page 111: ......
Page 112: ......
Page 113: ......
Page 114: ......
Page 115: ......
Page 116: ......
Page 117: ......
Page 118: ......
Page 119: ......
Page 120: ......
Page 121: ......
Page 122: ......
Page 123: ......
Page 124: ......
Page 125: ......
Page 126: ......
Page 127: ......
Page 128: ......
Page 129: ......
Page 130: ... 165 KX F680BX KX F2681BX EC1 EC2 EC3 EC4 EC5 EC6 EC7 EC9 EC10 EC11 EC12 EC13 EC8 TOOLS ...
Page 131: ......
Page 133: ......
Page 134: ......
Page 135: ......
Page 136: ......