More details about resistance & capacitance

[Apophis99942]

Hi there, I'm new here. A master student. I'm trying to make a mainboard-v05 for my 0.25U Cubesat. I have two questions.

First, I'd saw the bom. But I don't know the detail's about the resistance and capacitance. What manufacture name do you buy? what is their tolerance and temperature coefficient? where could find that detailed information?

Second, I found some of the sensors had been stopped producing. Like the IMUs---BMX160. Do you decide to change the sensor in the future? or what IMUs do you decide to change?

thank you

Eric Chu

[maholli]

Hi Eric!

1. All that info is included in the BOM :) They're linked on every hardware page, but here's the interactive BOM for mainboardv05. As shown below, the "Description" column contains the tolerance, temperature coefficient (X7R, X5R, etc...) and any other necessary details. Manufacturer is whatever you want as long as your reach those specs.

   

2. The BMX160 IMU (and any other ICs on the board) are all in active production. Keep in mind there is a global chip shortage right now, meaning you wont find anything in stock these days, but that doesn't mean the manufacturer has stopped producing that product.

Hope this helps! Let me know if you have more questions.

[Apophis99942]

Hi Maholli,

Thank you for the reply.
I'd seen that BOM. Something needs to double checked. At the resistance, some of the descriptions did not have more detail. Like R20, R36... doesn't have more detail about their tolerance and temperature coefficient. Is that mean those are no limits?

thank you

Eric

[maholli]

Hey Eric,

If a tolerance isn't listed, that means it doesn't have a hard requirement. You can use +/-1%, +/-5%, etc... Whatever fits your budget/vendor/distributor needs.

It's a hard balance between "enough detail" and "too much detail," and the latter can severely limit purchasing options. I'll find a way to better communicate this on future BOMs. 😄