CMOS driver stage for multi media card, smart card

摘要

The driver stage has an output drive stage and at least one pre-drive stage to control the output driver. The output drive stage consists of one or more p- and n-channel output switching transistors. In series to each transistor is one or more in cascade arrangement, p- or n- channel output current transistors to set the output drive current level. The output drive level is adjusted when the load changes. The output drive current level is independent of variations in the supply voltage source. The pre-driver is formed on inverters with switching controlled via pre-drive current transistors connected in series to the inverter transistors. The pre-drive current transistors are connected in cascade so the control current is adjustable in steps.