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LVDS receiver works as a comparator ?
I just got a question from our disty about LVDS products. According to our disty, their customer plans to replace MAX comparator (MAX912) to our LVDS receiver.
1) Do you know that several customers are using LVDS as a comparator ?
2) If (1) is Yes, which part do you recommend for the alternative of MAX912 ? SN65LVDS2 ? --- the requirements of the customers are 25MHz operation and 3.3V PS but 5V tolerant.
Yes, we have had customers use LVDS receivers as comparators. I would recommend that the customer look into the SN65LVDS34 (datasheet attached). The LVDS34 is a dual LVDS receiver that takes a 3.3-V supply but can tolerate 5-V inputs. It can operate at up to 400 Mbps.
I noticed that the MAX912 has complementary TTL outputs (e.g. the true signal and it's inverse). Our part does not have the inverted TTL output, so if that is a customer requirement then we will need to look into an alternate solution. The LVDS34 is also not a drop-in replacement, so let me know if that is necessary.
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Thanks for your answer.
But I noticed the contrariety in the datasheet. "input voltage range" of ABSOLUTE MAXIMUM RATINGS on page 3 say that A,B input range is -0.5V to 4V even though 5V tolerant. Could you let me know which is true ?
Are you looking at the SN65LVDS34 datasheet that I attached in my previous message? In that file, there should be an Absolute Maximum Ratings table on page 4 that lists the A or B voltage range as -5 V to 6 V. The supply voltage range (Vcc) is -.5 V to 4 V, but the A/B pins are 5-V tolerant.
Here is a link to the product page: http://focus.tij.co.jp/jp/docs/prod/folders/print/sn65lvds34.html
I hope this can clear up any confusion.
Thanks for your prompt reply.
My question was about NOT only SN65LVDS34 but also SN65LVD2. How about SN65LVD2 ? It seems like only 4V input even though 5V tolerant.
The SN65LVDS2 receiver inputs (A and B) are not 5-V tolerant, and the Absolute Maximum Ratings table on page 3 is correct. The LVDS2 datasheet also contains information about the LVDS1, which is a driver. It is the LVDS1 (not the LVDS2) that has 5-V tolerant input.
Sorry for any confusion.
I got it thanks !
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