FDC2212: Why cannot I active the second channel?

Dengkuan Sun

Part Number: FDC2212

Tool/software:

Hi Experter,

I am trying to use two channels to measure the proximity sensor. Currently, the first channel can work. But, the second channel cannot work. Can you help this?

I list my configured parameters:

{RCOUNT_CH0, 0xFF, 0xFF};
{OFFSET_CH0, 0x00, 0x00};
{SETTLERCOUNT_CH0, 0x04, 0x00};
{CLOCK_DIVIDERS_CH0, 0x10, 0x01};

{RCOUNT_CH1, 0xFF, 0xFF};
{OFFSET_CH1, 0x00, 0x00};
{SETTLERCOUNT_CH1, 0x04, 0x00};
{CLOCK_DIVIDERS_CH1, 0x10, 0x01};

{FDC_STATUS_CONFIG, 0x00, 0x01};
{FDC_CONFIG, 0x16, 0x41};
{MUX_CONFIG, 0x82, 0x0D};
{RESET_DEV, 0x00, 0x00};

{DRIVE_CURRENT_CH0, 0xF8, 0x00};
{DRIVE_CURRENT_CH1, 0xF8, 0x00};

Thanks

30 days ago

0 John Miller - Sensing 29 days ago

TI__Mastermind 40295 points

Dengkuan,

Are you using our EVM or your own custom PCB?
If it is custom, can you provide a schematic?

Regards,
John

0 Dengkuan Sun 29 days ago in reply to John Miller - Sensing

Prodigy 240 points

Hi John，

It is custim，but it is the same as the EVM.

0 Dengkuan Sun 28 days ago in reply to Dengkuan Sun

Prodigy 240 points

Also, pls help to check whether the circuit topology impact the proximity measurement. For two channels, pls help to check my register configuration based on the first post. The I2C works, but I only read a un-change value from channel two.

0 John Miller - Sensing 28 days ago in reply to Dengkuan Sun

TI__Mastermind 40295 points

Dengkuan,

I'll review the info and update this thread by COB on Thursday.

Regards,
John

0 John Miller - Sensing 22 days ago in reply to John Miller - Sensing

TI__Mastermind 40295 points

Dengkuan,

A couple of suggestions:

If your sensors are the same, please try making the non-working channel's registers the same as the working channel's registers and see if that helps.
If your two sensors are different designs, try swapping the sensors and register settings and see if the problem follows the sensors.
Try removing the common-mode chokes and see if that changes the failing channel's behavior.

Regards,
John

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FDC2212: Why cannot I active the second channel?