Products > Test Equipment
Keithley 2400 SourceMeter review and teardown
etrash2000:
Thanks for the list. I will have look on that.
A question, according to the data-sheets, SST39SF020A is a 5V only device for reading/writing while the original AM28F020 requires 5V for reading and 12V for writing. How can the Keithley 2400 write to the memory since the Vpp is not connected on the SST39SF020A?
z01z:
Well, what surely works is using the same flash as the original. Any other type is a gamble.
Any same sized flash most probably works if programmed externally, I'd still check pin layout and waveforms.
Whether in circuit programming works or not will only turn out if tried, it is only a theory that if the type is supported by the flash wizard, it will be programmed.
What you've notice isn't the only difference, the programming word sequence also differs. It is possible to read manufacturer and device ID from these chips. Based on this info the correct algorithm can be executed, if implemented by the programming bootloader. But again, this is a gamble.
etrash2000:
A short update for the interested ones.
I manages to save my bricked Keithley 2400 device by using the recommended TL866A programmer with a 4 MBit memory module SST39SF040-70-4C-NHE.
I did the programming directly on the TL886. I did not dare to use ICSP since I did not have clear instruction and the pinout of the Keithley.
The programming step was straight forward and worked on the first try. I used the even+odd C31 firmware supplied by TiN on xDevs.com
The calibration seems to be OK but I will probably do a new calibration of the unit this summer by using the script TiN has written for HP 3458A.
The next step will be to do a noise analysis of the unit as z01z suggested. Pictures will be up within a few weeks (too much work right now).
So, a big thanks to all and specially TiN for the files and instructions.
Kind regards
Colnago:
2400LV stopped functioning while measuring.
Digital part seems to function to the extent that I could even upgrade the firmware to C33 but still no readings, only '----'.
When switching on output it shows +23,977V when measuring voltage, 0,0003A for current and overflow for resistance. Hardly any change when holding leads together (voltage signs changes, current slightly decreases).
All buttons are functioning, reset to factory defaults, communicates (*IDN?, *TST? etc) through GPIB but no readings.
Keithley have a €1800 flat rate which is outside the budget so any suggestion is more than welcome!
TiN:
Standard, take it apart and check pass transistors on power stage. You can check gate resistance to source/drain first.
If all are ok, then you can measure live voltages, to see if all power rails are ok.
Be careful, there are +220/-220V voltages present, pay attention to correct ground referencing during measurement.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version