Check item(19).
Check the power supply voltage.
:
Does the power supply voltage of the DSP [
IC781
]
indicate the appropriate voltage (1.0V, 3.3V)?
The test points are as follows.
IC781
C7807 C7806
1.0V
3.3V
Check item(20).
Check the power supply voltage.
:
Check the power supply components [
IC741,
IC743, Q7415
] on the substrate and peripheral
pattern.
If there is no problem, remove the DSP [
IC781
]
from the substrate and measure the voltage at
the test point of
check item (19)
.
Is the voltage correct (1.0 V or 3.3 V)?
Check the power supply voltage.
Checking device. [
IC781 : CS49844A
]
Go to next page.
3-5. Error Code H1-08 failure detection procedure
NO
DSP [
IC781
] is faulty.
Replace with a new device.
Recheck from
check item (1).
If it does not work, replace the PCB.
The power supply circuit is faulty.
Replace the PCB.
NO
YES
YES
Check item(21).
Checking the reset :
Check the CPU.
Is the waveform of the TP near the DSP [
IC781
] correct (like the one
shown in the diagram) when the power is turned on?
IC781
32 pin
Checking the reset waveform.
Recheck from
check item (1).
If it does not work, replace the PCB.
Check the reset circuit between CPU [
IC751
] and DSP [
IC781
].
If there is no problem, the DSP [
IC781
] is faulty.
Replace with a new device.
NO
YES
Examples of confirmation waveform
Voltage scale：1.0V/div
Time scale：20ms/div
86
Caution in
servicing
Electrical
Mechanical
Repair Information
Updating
Содержание AVR-S730H
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