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Customer Satisfactions

  • From Richard in Germany:

    Hi Ben,Just wanted to say thanks to you and your team, you had a good performance on VXF-72V0233 productions leadtime, I know May beginning is your holidays, finally the high quali...

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  • From Angelia in Poland:

    Hi Gloria, Thanks for your following, glad to had chat with you in exhibition, I think you CDX is proper to our product structure and we will send some inquiries after we back Poland.

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  • From Suraj in India:

    Hi Ben, I think your suggestion on the panel design can be worked, so we can make cost down now for KAWU production, thanks for your help and I will send more series RFQs to you!

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  • From Maria in U.S.:

     Dear Gloria,Good news, your factory\'s sample was passed on customer product, then I think  CDX capabilities is no problem now, we will consider to meet your shop next week an...

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  • From Eric in Russia:

    Dear Mario, Good day! Many appreciation for your work on my job PN:AT901BS_v2 , I received it 3 days early than my expect date . it would help me to meet my customer's ship date. Thanks for your help again!

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CDXPCB introduce you to repair the detection circuit board

Date: 2014-10-30 20:21:20     From: CDXPCB
A chip with program.

1.EPROM chip are generally not damaged. Because of the need to remove UV chip program, so in the program will not damage test. But according to the data: for making chip materials, with the passage of time (year long), even without also has the potential to damage (mainly refers to the procedure so as to give). Backup.

2.EEPROM, SPROM and RAM chip with battery, were prone to failure procedure. This kind of chip is in use the < VI curve scanning tester >, whether or not they destroyed the procedure, is still a matter of debate. In spite of this, colleagues in the face of this situation, or be careful. The author has done many tests, might be a major reason is: maintenance tools (such as tester, electric iron) shell leakage caused by.

3 for the circuit board is provided with a battery chip not easily detach it from the board.
Reset circuit two.
1 to be a large scale integrated circuit to fix the circuit board, attention should be paid to reset.
2 before the test had better install equipment back, repeatedly opened and closed, the machine try. And press the reset button several times.
Three function and parameter test.

Detection of the device 1.< tester >, can only reflect the cutoff region, amplification and saturation regions. But cannot detect the level of working frequency and the speed of the specific numerical.
2 similarly to the TTL digital chip, also can know the output level changes. To find out the speed of its rise and fall along.

Four. Crystal oscillator
1 usually only use oscilloscope (crystal add electric) test or the frequency meter, multimeter etc. can not be measured, otherwise can only adopt the method of substitution.
The common fault of 2 Crystal: A. internal leakage, internal B. open C. modification frequency offset D. peripheral connected capacitor leakage leakage phenomenon. Here, use the < VI > curve tester should be able to detect.
3 the whole board test can use two methods: A. test on chip crystal oscillator is not near around by.B. in addition to crystal outside did not find other fault.
4 crystal common has 2 kinds: A. feet.B. legs, wherein the second foot is to add power, careful not to arbitrarily short.

Five. Distribution of fault phenomena
Incomplete statistics 1 circuit board fault location: 1) chip damage 30%, 2) discrete component damage 30%,
3) connection (PCB board deposited copper) fracture 30%, 4) program is damaged or lost 10% (upward trend).
2 from that, when to repair the circuit board line and procedures when there is a problem, and there is no good board, neither familiar with the line, the original program not found. This board fixed possibility is not big.