Looking for I2C or SPI transceiver!!!

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I'll be brief.
I want to make a single-rocket launch controller, with a 50m cablec dual line. I'll use a differential line. I'll put a i2c or an SPI I/O extender on the far-away part.

So I need dual line transceivers, like SN-75176, but for SPI or I2C. BUT I can't find anything like that. I've been goooogling, but with no result. And I don't want to put MCUs on both ends. Is there an IC like that, or I'm in a dead end? :roll:

-Angel Angelov
"Humans are stupid."
I'm probably working on a scratch-build rocket or on a PCB

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What >>are<< you going to put on the other end? Apparently some type of SPI or I2C decoder/driver?

Say that costs $0.25. Put in a $2 ATtiny2313 or ATmega48, and use RS-485 transceivers.

[And given the above what would the compellnig reason be to not have an AVR on the other end?]

Lee

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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DexterLB wrote:
So I need dual line transceivers, like SN-75176, but for SPI or I2C. BUT I can't find anything like that. I've been goooogling, but with no result.

For I²C devices look at NXP's (formerly Philips Semiconductor) website, they are the inventors of I²C and has the largest selection of specialty I²C devices and the most extensive I²C documentation: http://www.nxp.com/#/pip/pip=[pf...|pp=[t=pfp,i=41735]|

I²C repeaters/hubs/extenders: http://www.standardics.nxp.com/p...

Quote:
Long Distance I²C or SMBus
The P82B715 and P82B96 are specifically designed to extend the reach of the I²C or SMBus over long distances, in the range of kilometers, depending on the maximum bus speed. This allows the designer to use I²C to interconnect equipment cabinets or for large area systems such as warehouse pick and place systems.

I²C Application Notes: http://www.standardics.nxp.com/s...

AN444 Using the P82B715 I²C Extender on Long Cables (June 1993): http://www.standardics.nxp.com/s...

AN460 Using the P82B96 for Bus Interface (Feb 14, 2001): http://www.standardics.nxp.com/s...

AN255-02 I²C/SMBus Repeaters, Hubs, and Expanders (Dec 19, 2002): http://www.standardics.nxp.com/s...

AN10658 Sending I²C-bus signals via long communications cables, V1 (Feb 26, 2008): http://www.standardics.nxp.com/s...

Quote:
Example B: 2 × P82B96 communicating at 400 kHz over 50 m of Cat5e twisted pair cable and exchanging 400 kHz Fast-mode I2C-bus compatible signals (i.e., 3 mA levels) with an Fm+ capable slave.
(In Example B, directly replacing P82B96 by PCA9600 would achieve the same 50 m performance with slightly improved timing margins, but more importantly, PCA9600 provides guaranteed TTL level compatibility at its Sx/Sy while P82B96 is only typically compatible with TTL logic levels.)

I would probably pick the PCA9600 which is a new higher-speed version of the P82B96.
(See AN10658 example B above).
If you chose P82B96, please note both NXP and TI makes this part (and P82B715 too).
TI I²C Hubs, Buffers, and Repeaters http://focus.ti.com/paramsearch/...

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Thank you! That helps a lot!!!!!

P.S. Happy easter! :)

-Angel Angelov
"Humans are stupid."
I'm probably working on a scratch-build rocket or on a PCB