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Topic: Ian, thank you for the free Flash_Destroyer PCB from Free PCB Sunday 05/30/2010 (Read 5810 times) previous topic - next topic

Ian, thank you for the free Flash_Destroyer PCB from Free PCB Sunday 05/30/2010

On May 30, 2010, I saw the Free PCB Sunday: Flash_Destroyer blog pop up and posted a comment.

Next Ian asked me where he shall send the PCB to and last Saturday (06/05/2010) it arrived ... yesterday I got the tiny 0.125W resistors, finally.

And now we have a second Flash_Destroyer sending a Microchip 24AA01-I/P EEPROM to the grave (while Windows Automatic Update is sending my PC to the grave in the background ...)! :D

 

When assembling the Flash_Destroyer I did two slight modifications:
a) instead of soldering the 7-segment LEDs directly on the PCB I installed single row DIP sockets
    ... to be able to remove the LEDs, put in LEDs with other colors ... for flexibility
b) and 2 4-contact female headers (Arduino style) instead of the DIP-8 socket for the EEPROM for easy extension/modification
    ... and built an adapter with an DIP-8 socket for the 24AA01.

 

All parts are through-hole so assembling the Flash_Destroyer is rather easy ...

Then I tested the assembled board for shorts and installed the bootloader with MPLAB and a PICKit3 (power must be connected to the Flash_Destroyer to program the PIC with an ICD or PICKit!) and used the bootloader to install FD-firmware-v1.1.hex.

 

... an other Flash_Destroyer sending an innocent EEPROM to SiO[sub:]2[/sub:] heaven ... (not sure what kind of glitch I caught on the first picture - the rightmost digit doesn't look like a number ;) )

 

Once the test is over, I plan to add a temperature sensor and run the test with an other 24AA01 at 85°C and with an automotive grade 24LC01B at 125°C ...

Ian, thanks for the PCB and most of all for sharing an other fun project!

Re: Ian, thank you for the free Flash_Destroyer PCB from Free PCB Sunday 05/30/2010

Reply #1
No problem. Thanks for the excellent writeup. It's always a huge relief when a project works for someone else for the first time :)

Great idea to test at the temperature limits. A Flash Destroyer in the oven with the pilot light on maybe.
Got a question? Please ask in the forum for the fastest answers.

Re: Ian, thank you for the free Flash_Destroyer PCB from Free PCB Sunday 05/30/2010

Reply #2
Pilot light, good idea ... but running an oven for a couple of days could be considered a waste of energy ... maybe there is an other option ...

A few details

1.  BC337-25 NPN transistors (Q2-Q8) with 10kΩ resistors (R3-R9) between the PIC I/O pins and  the base of the transistors to drive the LEDs cathodes CC (DIS1-DIS7)

2. 120Ω resistors (R10-R17) to drive the LED anodes a-g and dp

as suggested by rsdio. I suggest you correct the large image of the schematic accordingly (still shows BC547 and 100Ω). Actually the anode resitors should be 125Ω or more for the LEDs I used but since we have a 1/7 duty cycle of a few ms the average current drawn from the PIC should stay well below 175mA at all times.

3. for the 7-segment LEDs (DIS1-DIS7) I used Kingbright SC56-11SURKWA super red LEDs (V[sub:]Fmax[/sub:] = 2,5V, 20mA (I[sub:]Fmax[/sub:] = 30mA) - 0,47 € @ reichelt.de)
    alternative/other colors from Kingsbright would be:
    - yellow SC56-11YWA (0,42 €)
    - green SC56-11GWA (0,42 €)
    - (standard) red SC56-11EWA (0,45 €)

P.S. After 3 days and about 11h the Flash_Destroyer is at 3,85 million cycles ... and flashing away.

Re: Ian, thank you for the free Flash_Destroyer PCB from Free PCB Sunday 05/30/2010

Reply #3
At 8.8 million the Flash_Destroyer lost power (unintentionally, without previously pushing the "save" button) ... so when power was applied again it started counting from a little over 10.000 (must have been the saved value from my "save" test) ... up to 5.5 million before it showed "dead" - a total of about 14.3 million cyles, not bad for a 24AA01-I/P!