Author Topic: TI says that 3.3v transceivers are OK for CAN bus. Is their report convincing?  (Read 1808 times)

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Offline e100Topic starter

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According to this http://www.ti.com/lit/an/slla337/slla337.pdf there is no disadvantage to using 3.3v over 5v, or mixing 3.3 and 5v devices on the same bus.
 

Offline T3sl4co1l

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I would expect a reduction in range, but only by a modest ratio, not like orders of magnitude.  The common mode emission is annoying, and makes a CMC just about mandatory; but they're commonly found, anyway, so that's probably a non-issue.

CAN was derived from RS-485; there's been 3.3V RS-485 transmitters for a long time.  The original RS-485 transmitters were implemented in TTL, which only delivers about 3.5V tops, which LVCMOS easily matches.

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Offline rsjsouza

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Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 

Offline Scrts

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All automotive designs I've seen so far, even designed today for vehicles to be released in 2022-2023 still use transceivers powered from Vcc=5V, but VIO is set to 3.3V.
 

Offline Tomorokoshi

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We use the TI transceivers from powered from 3.3V with a 125 kbps data rate with no problems.
 

Offline rvalente

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All automotive designs I've seen so far, even designed today for vehicles to be released in 2022-2023 still use transceivers powered from Vcc=5V, but VIO is set to 3.3V.

What transceivers are companies using today? Last time I've worked with OEM automotive we where using TJA1054 and TJA1050, there was a newer version of 1054 in 3v3

We use the TI transceivers from powered from 3.3V with a 125 kbps data rate with no problems.

Would it be for automotive or industrial equipment? Which PN have you been using?
 

Offline Tomorokoshi

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We use the SN65HVD230DR in industrial equipment at 3.3V.

https://www.digikey.com/products/en?keywords=296-11654-1-ND
 
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Offline Mazo

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As someone working in the automotive business,TJA1042 and TJA1055 are widely used by the company I work for(major supplier for a lot of car makers).
All supplied by 5V.
 


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