pull-up sd card

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noobish question. can i add a pull-up resistor to resistor voltage divider?

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Yes, but you shall alter the voltage. How much by depends on the comparative ratios of the pull up and the voltage divider itself.

For that reason, I would not recommend it. If you need a supply rail then use a regulator.

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i have already a supply voltage(made it from +5v and few diodes connected in series). i need pull-ups for talking lines. the problem is that i cannot initialize my sd card and i checked almost everything, power suply seems ok, speed is 125kHz during initialisation, i give quite a bit of time for voltage stabilisation and CMD0, so now it's only pull-ups and mistakes in the code left.

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i was thinking about diodes, but simple ones probably support only very low frequency. i mean if i use diodes, i can use pull-ups with them.

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so is there a way besides buying a chip for level shifting?

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i guess it's not worth the effort, i'll just buy a chip.

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Somewhere I read that some newer SD cards rely on edge transition and therefore don't work well with a resistive level shifter.