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MKV58 vs. i.MX RT

Question asked by Andrea Canepa on Apr 23, 2018
Latest reply on Apr 26, 2018 by Andrea Canepa

The question is simple: in 2018 is it worthwhile developing a new project using MKV58 (kinetis)?

In 2018 the i.MX RT 1050 was officially released, and in a few months i.MX RT1020 will be available, so what is the point now to consider using MKV58?

The i.MX RT use Cortex M7 (like MKV58), they have a price that can be 1/2 or 1/3 compared to MKV58, have lead times of 14 weeks (compared to MKV58 which today has a 39 weeks !!!), they are fresh products.

If we compare i.MX RT1020 with MKV58 they have the same package (144 LQFP), they have about the same peripheral equipment, moreover i.MX RT also has the integrated USB and the interface for SD cards (uSD, SDHC, etc. ) that many of us wanted in MKV58.

i.MX RT1020 has the clock frequency up to 500 MHz, while MKV58 stops at 240MHz.

i.MX RT1020 has the RTC, while MKV58 does not have it.

Perhaps the most negative aspect in i.MX RT1020 is that it no longer contains the intergrated flash, but it could also be considered positive if we think about the freedom to mount the model and the amount of flash needed outside (but we complicate a little life to make the reading of external data safe).

As for the analog part, i.MX RT1020 seems worse than MKV58: i.MX RT1020 has lost the 16 bit ADC vs. MKV58, (but the conversion quality of that 16 bit ADC has never been exceptional, it is very susceptible to internal noise and it is mandatory to run several averages of the signal to get a good result, so it's not a great loss). But the downside is that i.MX RT lost the fast (5MSPS) HSADC 12 bit with the differential inputs that the MKV58 had inherited from the DSC family (56F83xxx and 56F84xxx), replaced by a normal 12 bit (1MSPS) SAR.

i.MX RT also lost the DAC!

My impression is that i.MX RT1020 has lost many "analog" qualities compared to MKV58 but that has gained a lot in digital peripherals: the FlexIO for example is very interesting.

What is my concern? What little by little NXP is trying to "pull" exFreescale (and exMotorola) customers to their processors, implementing the pricing and delivery time policy: how is it possible that two similar microcontrollers can have such a big difference in price and lead time?

Probably if the application does not require the analogue part missing in i.MX RT, the right choice would be to use it in a new project.

I would like everyone to write his opinion about it, even analyzing the comparison between the two microcontrollers, to hear the opinion of NXP regarding my statements, to understand how the situation is now. Why does NXP have many similar components in its portfolio? What is the convenience of having all this?