Tom Handley wrote:

>   Morgan, thanks for sharing that! I've been using a couple of LTC2400s in
>a PIC-based DAQ system that has been running about a year. In my case, I use
>the External SCK/Single Cycle mode rather than the polling the EOC Bit. I
>don't know what your requirements are but it's a lot easier to monitor EOC.

It is, but I am saving pins for future use, and have to time-interleave a few SPI devices on the MSSP module.  The SPI communication wil intruduce a slight noise based error on the measuremet, but we do not need extreme precision.  Maybe just a few designers use the polled mode because of the introduced noise, and therefor the bug has not been detected?

-snip-

>  As far as timing, I'm using a 16F877 at 20MHz. Assuming EOC is complete
>and SDO is Low, there is a 1us delay from the falling edge of /CS to the
>rising edge of the first SCK pulse. The SCK pulse-pulse delay is 2us. This
>was added during testing and I never tried to speed it up.

I have experimentally run at 1MHz clock, no problem. That was the highest speed "Xtal/4" i could get in the MSSP module at my 4MHz Xtal. I am normally running it at /16.

>At 02:34 PM 11/4/00 +0100, Morgan Olsson wrote:
>>This week we proved a stupid bug lurking in the SPI interface in the
>>well-known LTC2400 analog to digital converter from Linear Technology.
>>(tested chips produced week 41, 1998)
>[Bug description snipped]


Not yet any response from LT on my bug description.
I plan tomorrow to test if the bug is till left in a newer chip revision.

Regards
/Morgan

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