Hi there, I'm using both these modules to communicate with an MSP, and my question lies the /RE and DE pins of the IC's respectively, I know these are enable pins but is there any limit to what resistor value you can connect there? I was asked to do an assessment on optimizing a circuit's BOM and there's a resistor value I'd like to change and I'd like to know what impact does that originate.
Currently I have a 33k resistor connected between the /RE pin and the MSP for the ISL32610 and another 33k connected from DE to VCC in ISL32613, what would happen if I changed both those resistors to 36k?

Below there's an image of both schematics.

Thanks in advance
Gabriel

 

Hi there, I'm using both these modules to communicate with an MSP, and my question lies the /RE and DE pins of the IC's respectively, I know these are enable pins but is there any limit to what resistor value you can connect there? I was asked to do an assessment on optimizing a circuit's BOM and there's a resistor value I'd like to change and I'd like to know what impact does that originate.
Currently I have a 33k resistor connected between the /RE pin and the MSP for the ISL32610 and another 33k connected from DE to VCC in ISL32613, what would happen if I changed both those resistors to 36k?

Below there's an image of both schematics.

Thanks in advance
Gabriel

Hello,
the ISL32610 has no /RE pin. The device you're talking about is the ISL32611.
The enable pins of the ISl32611 (/RE) and the ISL32613 (DE) have internal pull-down and pull-up resistors in the 100k range. You don't need any resistors in series to the pins. However, external biasing resistors in the 1k to 2k range are recommended if the disabling of the device is not needed.
For the /RE pin of the ISL32611 receiver connect the /RE pin directly to ground.
For the DE pin of the ISL32613 driver connect the DE pin via a 1k or 2k resistor to Vcc.
Best Regards, Tom