Potentiometer 4132-502 E/P

Good morning
I have a problem with a digital potentiometer MCP 4132 -502 E/P
I sen the data with SPI and the potentiometer grow the resistance " with step".
I don’t understand why, start of 0 go to 500-600 ohm in linearity, after go to 1200 after to 2400 after to 4800 ohm.
I don’t have the charge wire it, the potentiometer is wired with tester.

Hello,

We are taking a look at this issue and will be able to get back to you as soon as we get a plan on what is the best trouble shooting steps to take.

I have 8 potentiometer and have the same problems.
I use the SPI imput but the potentiometer doesn’t work
The potentiometer work when i write :
Memory address 0 and data set with only number that have 1 in binary.
Example: address 0 , data 63 (111111 binary ) work
Address 0, data 62 or 64 ( 111110 or 1000000 ) doesn’t work.
Incremental and decremental setup ( address 00000100 and 00001000 ) doesn’t work.
Actually i use x9c104 with 1000 - 1500 pcs per year your potentiometer has better resolution but i need that it’s work.

When many different devices all behave in the same way, this is often a sign that there is a problem with how they are being used, rather than with the devices themselves.

Could you please describe the serial data values exactly as they are sent, and what the resulting resistance across the device’s output is? It is unclear what you mean when you say simply that the device “works” or “doesn’t work”. The 4132 device has 7 bits of resolution but 10 bits of data width in a 16-bit command sequence, so how the data is shifted within the command may be part of the problem.

Sending 0x04 should increment and 0x08 should decrement, but these functions are disabled if the device is already at it’s maximum travel.

Monitoring the output of the device’s SDO pin may offer clues; if it goes low on bit 7 of a command, this indicates that the device believes that the command is invalid.

Observing the SPI transactions directly using an oscilloscope to ensure that all timing and voltage level requirements are met can also be a useful diagnostic step.

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