X9C103 changing to MAX5451 or MAX5389

[aless2056]

Guys, I'm going to exchange a digital potentiometer X9C103 that is used connected to the RT of an SG3525.

The goal is to have more resolution, more steps since X9C103 is 100 steps and MAX5451 or MAX5389 is 256 steps.

Controlling the X9C103 today is done by a PICF628A.

The questions are as follows:

1) The Max5451 or Max5389 look the same to me, I just see that the Max5389 is a newer item, I didn't see any difference between them in relation to the X9C103, the more experienced ones tell me.

2) The uc is connected to X9C103 using this board below, in which I have 4 capacitors, I believe it is one for each IC input X9C103 in relation to ground and one on vdd, am I correct?

The pins and outputs of the direct uc can I connect directly to the control pins of the IC Max5451 or Max5389, without putting a resistor or capacitor?

[RES]

The MAX5451 has shared U/D and INC pins (so toggle each pot/wiper with Chip Select pins), while the MAX5389 has separate control pins. Yes you can directly connect the control pins (5V).

[aless2056]

As an example, remembering that I am a beginner in electronics. I'm going to use MAX5389 or MAX5451 in place of the RT resistor on an SG3525. As I know, as an example, which current leaves the SG3525 and passes through the RT, and where I find in the datasheet the maximum current of the resistance of the MAX5389.