Unable to program KL03 below 2.7VDC

[aboss]

In conjunction with Kinetis Design Studio, I am using a Multilink Universal device to program NXP MKL03Z32CAFR MCUs that are powered off of a 2.1 V supply in my design. I am getting a P&E Connection Assistant message when my MCU is powered from 2.1 V, and cannot program the MCU. When the MCU is powered at 3 V, I do not get the error and can successfully program the MCU.

The only way I am able to program my MCU at 2.1V is to first use the Kinetis Recovery Tool utility to halt the processor.

Are there other flash algorithms that will automatically halt the processor immediately upon startup? Any suggestions would be helpful.

-Andrew

[jingpan]

Hi Andrew,

There isn't other flash algorithm. You have to find out why the mcu brick. KL03 can be programed at 1.8V. I guess below 2.7V the MCU is affected by other device and circuits on the board, or by improper setting. I attached some links you can refer to.  They are for KL25. But KL03 is also fit for it.

kinetis KL2x programming voltage @ 1.8V 

https://community.nxp.com/message/304539 

Regards,

Jing

[aboss]

Thank you for the information Jing. I have made modifications to my board by removing all of the non-essential components required for programming. All that remains is the MCU, 10k pull up resistor on the reset pin and a 0.1 uF decoupling capacitor for the MCU power pin, along with the traces leading to the SWD programming connector, i.e. only parts related to the SWD interface. I am still unable to program the MCU at supply voltages below 2.7 V, unless I first halt the processor using the Kinetis Recovery Tool. I only have success without using the Kinetis Recovery Tool with voltages above 2.7 V.

The MCU I am working with on my board was ordered from our CM back in June of 2018. If I try a simple breadboard setup with an MCU that was ordered over two years ago, I do not have an issue programming at voltages below 2.7 V. Please note that the breadboard setup and my PCB setup are similar in nature now that I have removed all non-SWD related components.

I am suspecting the core is going into an infinite reset once it detects the supply is below 2.7 V based on Table 7 of section 2.2.2 of the KL03 Reference Manual.

-Andrew

[jingpan]

Hi Andrew,

Please check PMC_LVDSC1 register. By default, LVDRE=1 and LVDV=0. This mean LVD reset enable and low trip point selected. The V LVDL is around 1.60v(datasheet Table 6). If you change this setting to LVDH, reset will occur.

Regards,

Jing