Transistor on SPI line to SD-Card? (Write operation 100mA)


I've been reading about SD-cards a bit, and it looks like they could be consuming up to 100mA during write operations, that's way above what an Atmega328p pin can handle. Do I need to use a transistor? If so, on which line, MOSI?


The SD cards may take even more, not from an SPI signal pin, but from Vcc for the sdcard (3.3Volt !). The Vcc is not connected to the atmega328p's SPI pins.

oh, I c, thanks. Then it's not a problem since my SD module has a 3.3. voltage regulator included, I'll just use an extra (5V) power supply for it.

Now I only need to make some level shifters. I think I'll go for the resistor+zener diode circuit.