LDC2114EVM: Operates in stand-alone mode after register rewrite of LDC2114 EVM

Hello,

It is possible to write new register values to the LDC2114. What I would recommend is building your setup without the MCU and connecting this to the MCU side of the LDC2114EVM. Power up your board using an external supply, use the GUI to program the register values you want, and then disconnect the LDC2114 from the MCU.

Best Regards,

Hello. Mr.Kristin

Thank you for your reply immediately.

It means that LDC2114 can operate without MCU.

(Are you aware that all functions such as base tracking will also work?)

In the case of the LDC2114EVM, the LDC2114 mounting board and the MCU (MSP430) mounting board can be divided, so when writing registers, connect the two boards and remove the MCU board after rewriting the registers.

When the MCU board is attached again and the power is turned on, the default (in MCU FW) register settings will be loaded again.

There are two requests below.

1 Please tell me the concrete procedure of register rewriting.

2 Are there any documents written about the standalone operation of the LDC2114?

Best regards

Hello,

Yes, all internal algorithms will work. The only function that will be unavailable is I2C communication, because this inherently requires an MCU. 

You can write any register settings you prefer to the device using the Registers tab of the Sensing Solutions GUI. More information is available in the LDC2114EVM user's guide. After writing the registers, the MCU should be disconnected from the LDC2114. The MCU should not be power-cycled while connected to the LDC2114 or it will overwrite the custom register values with the default register values.

We don't have any documents written about using the LDC2114 without an MCU.

Best Regards,

Dear Mr. Kristin

Thank you for your quick reply.

I understood.

If MCU is disconnected from LDC2114, it means that the register will not be rewritten?

Please let me ask you one more question.

■ Processing of LPWRB pin when using standalone

When using LDC2114EVM as a standalone, I think that the LPWRB pin needs to be tied to 1.8V or GND. Do I need to add 0 ohms to the resistor R33 or R35 on the B side of the board, right?
When installing the MSP430 board on the LDC2114 board again, I worry about the batting with the LPWRB signal from the MCU to the LDC2114. Level shifter-the LPWRB terminal of U3 may be broken. If there is a protection circuit, it may not be a problem.
It is nonsense to remove R33 or R35 every time I install the MSP430 board.

Please give me some advice.

Best regards

Hello,

If the MCU is disconnected from the LDC2114, the registers will not be rewritten. However, if the LDC2114 is power-cycled the registers will be rewritten to their default values listed in the datasheet.

You can populate R33 or R35, or you can tie the LPWRB through-hole connector directly to 1.8V or GND.

While the LDC2114 can run without an MCU, it's really not meant to permanently operate without one. The intended operation is that the LDC2114 can operate in low-power mode while the connected MCU is in sleep mode, then send a signal to wake the MCU when a button press is detected. If you are looking for an LDC device for button detection that can operate without ever needing an MCU, I would suggest the LDC0851.

Best Regards,

Thank you for your reply.

> If the MCU is disconnected from the LDC2114, the registers will not be rewritten. However, if the LDC2114 is power-cycled the registers will be rewritten to their default values listed in the datasheet.

I am sorry, I cannot understand what you are saying.

Please check below.

Does it mean that after connecting the MCU board and rewriting the register value of LDC2114, all the register values of LDC2114 will return to the default values when the MCU board is removed and the LDC board is powered on again?

“The LDC2114 turns off the power, and the power is turned on again, the register value always returns to the default value” “When the LDC 2114 is turned off, it is all over”

Does that mean?

I think that I cannot use LDC2114 board in stand-alone mode.

Is there something wrong?

The LDC0851 is a stand-alone sensor IC. (The LDC0851 is a simple sensor that cannot be connected to the CPU.)

I will think about it.

The operating range is wide with “Operating Temperature Range: -40 to 125 ° C”.

It seems that there are only LDC1612-Q ICs for automotive use at this time, how is that?

If there are other automotive inductive sensor ICs, please introduce them.

Best regards.