Can you or someone else post a scheme with 100uf and 0.1uf capacitors included?
Caps often help and short wires are important. Even with these precautions many people have problems with resistor level shifters.I have done a study using cards with resistor level shifters. I find that most older cards work at 8 MHz and almost all older cards work at half speed, 4 MHz. Many newer cards fail at all speeds with resistor level shifters. These cards expect very fast SPI signal rise times. The SD spec requires a rise time of less than 10 ns for all clock speeds under 25 MHz. It is just not possible to get sharp edges at 8 MHz into the typical capacitance with resistor level shifters. New cards appear to use edge detectors. New cards expect 5 ns rise times for 25 - 50 MHz clock.
...With the tristate output, it could be used as a level shifter by tie-ing the input low, put a pullup to 3.3V on the output, and enable the input to bring the output low, disable the input to let it go to 3.3V for the SD card high input.
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