Hi,
wondering if someone can help. I acquired this CD player and it not ejecting. The mechanism is fine. The problem is I'm not getting any voltage from the motor control unit. I believe it from the chip PIC12C508A
All the voltages around the chip are fine. The components around that seem fine as I checked them with my volt meter.
I think the pins 2 and 3 are output to the motor but when the open/close button is pressed there is no voltage across those pins or the connector itself.
Also I cant seem to find D6 and D7 on the board, maybe the schematic is different to the board?
Any help appreciated!
wondering if someone can help. I acquired this CD player and it not ejecting. The mechanism is fine. The problem is I'm not getting any voltage from the motor control unit. I believe it from the chip PIC12C508A
All the voltages around the chip are fine. The components around that seem fine as I checked them with my volt meter.
I think the pins 2 and 3 are output to the motor but when the open/close button is pressed there is no voltage across those pins or the connector itself.
Also I cant seem to find D6 and D7 on the board, maybe the schematic is different to the board?
Any help appreciated!
Attachments
Look this datasheet of the BA6218.
BA6218 pdf, BA6218 Descripcion, BA6218 datasheets, BA6218 Vista ::: ALLDATASHEET :::
Look the "table of truth" in page 395, and look inputs in pins 1 and 3 and outputs pins in 7 and 9.
D6 and D7 looks to be part of power supply, maybe is in other pcb.
BA6218 pdf, BA6218 Descripcion, BA6218 datasheets, BA6218 Vista ::: ALLDATASHEET :::
Look the "table of truth" in page 395, and look inputs in pins 1 and 3 and outputs pins in 7 and 9.
D6 and D7 looks to be part of power supply, maybe is in other pcb.
You are absolutely right. This is what I found about the 2 chips, the PIC12C send signals the BA6218 chip and then the motors turns.
Took me all day of reading to understand this! The PIC12C is actually working perfectly, when the BA chip receives the signal is does nothing!!
I check supply voltage to the BA chip and it was 5V, in the service manual it states 8V supply. I checked and the BA can operate at 5V but does nothing. Everything as far as I know is correct expect for the BA chip.
The only question is, is the 5V supply ok or is that causing the issue?
Took me all day of reading to understand this! The PIC12C is actually working perfectly, when the BA chip receives the signal is does nothing!!
I check supply voltage to the BA chip and it was 5V, in the service manual it states 8V supply. I checked and the BA can operate at 5V but does nothing. Everything as far as I know is correct expect for the BA chip.
The only question is, is the 5V supply ok or is that causing the issue?
Why it is 5v instead 8v? You should see the power supply, the part of 8v. Maybe the IC damaged the 8v power supply, who knows... Maybe the power supply of this part is 5v. It must be checked for to remove any doubts.
You are right!
Heres what I discovered:
Bad belt makes the motor work constantly and thus heats up the circuitry, a few minutes of that and you have blown power supply.
In my case I found a few faulty PNP transistors in the power supply section. Found replacement and all good!
Something that simple took nearly 3 days and much learnt lesson!
Voltage is again 8v and functioning correctly!
Heres what I discovered:
Bad belt makes the motor work constantly and thus heats up the circuitry, a few minutes of that and you have blown power supply.
In my case I found a few faulty PNP transistors in the power supply section. Found replacement and all good!
Something that simple took nearly 3 days and much learnt lesson!
Voltage is again 8v and functioning correctly!