NFC problem with MK20FX512VMD12

[zohargolan]

Hi All,

I hope someone can help me with my problem as I have a long lasting problem with the external flash device.

We have a custom board with the KN20FX512VMC12 device mask 3N96B. On June 2016 (3 years after device release) NXP released an errata for this mask. One of the issues in the errata is e5927 Operating requirements: Change to minimum VDD spec. In this errata it says the minimum VDD voltage cannot be 1.8v anymore, but must be 2.0v. The errata does not mentions what blocks are affected by it and what are the implications of using the 1.8v instead of the 2.0v. Our custom board is of course using 1.8v as VDD and not 2.0v.

The reason I am interested in this errata is that we are using a NAND flash connected to this MCU and using the NFC on the chip to control the NAND flash. The flash is holding some configuration data and is only written in the production line and then only read at boot time.

Once in a while the flash is getting corrupted and the only solution for us is to re-write the content of the flash.

I appreciate any help with this matter

[miduo]

Hi,

Actually, the e5927 affects the device at “power on reset”, thus, it is recommended VDD at 2.0V as minimum. When DDR is used, VDD must be higher than VDD_DDR. The e5927 does not relate to flash corruption but affects the flash read at POR when VDD at 1.71 – 1.99 V. So with a voltage in that range there could be intermittent flash read issues at POR.