topic Re: LIN protocol in Other NXP Products

LIN protocol

hamid_abrishami — Tue, 12 Jul 2022 13:49:54 GMT

Hi every one

I want to chose LIN IC and have doubt between MC33662LEF and MC33662SEF because in data sheet said that MC33662SEF "20 kbps with restricted limits for
transmitter and receiver symmetry" but when I checked table 6 "Dynamic Electrical Characteristics" it seems that this IC meet all the spec of LIN protocol (propagation delay of receiver and Symmetry of receiver propagation limit 2 and 6 us for receiver) but for SEF part in data sheet in transmitter mode we have 7.25 us

BR

Re: LIN protocol

diazmarin09 — Tue, 12 Jul 2022 18:49:28 GMT

Hello,

First, please note that these devices are not recommended for new designs. You may consider such information for further designs.

You are correct, the 33662L and 33662S (20 kbps) have a slew rate and timing compatible with Normal Baud Rate and LIN protocol specifications 1.3, 2.0, 2.1, 2.2, 2.2A and ISO17987-3:2016.

Is the Symmetry of Transmitter delay parameter, out of your specs?

Have you considered the MC33662BSEF or MC33662BLEF devices (active status)?

I hope this information helps.

Regards,

David

Re: LIN protocol

hamid_abrishami — Wed, 13 Jul 2022 05:55:32 GMT

Hi David thanks for your reply
I don't find any parameter for Symmetry of Transmitter delay parameter in LIN standard.
yes I know that BLEF and BSEF in active now
but now my main question is that what is the difference between SEF and LEF part number Because both of them seems that support 20Kbps and which one is better ?

BR

Re: LIN protocol

diazmarin09 — Wed, 13 Jul 2022 21:06:49 GMT

Hello,

Thank you for using the NXP community.

For more information about the SEF and LEF part difference, please review the datasheet, section “Dynamical Electrical Characteristic”. There are specifications for “33662L” version and for “33662S” version, so you can see the difference.

Note that the versions without the ‘B’ letter in the part numbers are older ones which are affected by two problems mentioned in the footnote (higher current consumption in sleep mode and unexpected glitch). This is fixed on newer versions, the MC33662BSEF or MC33662BLEF devices.

I hope this information helps.

Regards,

David