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MAX 10: LVDS electrical characteristics and compatibility

Altera_Forum
Honored Contributor II
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I am intending to use MAX 10's true LVDS IOs for both TIA-644 and TIA-899. The True LVDS IOs mention that they can be used both for Tx and Rx. The electrical characteristics of MAX 10's LVDS differ from the standard LVDS (TIA-644) and M-LVDS (TIA-899) as detailed below: 

 

 

 

 

MAX 10 

TIA-644 

TIA-899 

 

 

Vos (V) 

1.125 - 1.375 

1.125 - 1.375 

0.3 - 2.1 

 

 

Vod (mV) 

247 - 600 

247 - 454 

480 - 650 

 

 

 

Can MAX 10's IOs still be used for both of these standards? If yes how? Do I need to use a differential to differential amplifier in case of TIA-899? 

 

Secondly my understanding of the difference between True LVDS and Emulated LVDS is that former's receiver is terminated internally and thus does not need an external termination. Please correct me if I am wrong.
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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

Secondly my understanding of the difference between True LVDS and Emulated LVDS is that former's receiver is terminated internally and thus does not need an external termination. Please correct me if I am wrong. 

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Not quite right. Emulated LVDS is a TX feature. LVDS RX are true LVDS receivers on all banks where they are available. MAX10 doesn't provide on-chip parallel termination for LVDS RX. Cyclone V e.g. does. See this doc https://www.altera.com/content/altera-www/global/en_us/index/documentation/sam1394433606063.html 

 

MAX10 can basically implement Bus-LVDS (M-LVDS), the specifications are almost similar to TIA-899.
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Altera_Forum
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Thanks for clearing the termination issue. 

 

But how this mismatch of offset voltage is going to be catered for? MAX 10 has a Vos of 1.125 - 1.375 V whereas TIA-899 has a Vos of 0.3 - 2.1 V.
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Altera_Forum
Honored Contributor II
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--- Quote Start ---  

But how this mismatch of offset voltage is going to be catered for? MAX 10 has a Vos of 1.125 - 1.375 V whereas TIA-899 has a Vos of 0.3 - 2.1 V. 

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I guess you don't fully understand the meaning of the parameters. Vos is output common range, the effective requirement is that Vos extrema of all M-LVDS transmitters are within the guaranteed Vicm range of all receivers.
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