Diode Transistor Logic Component
Tuesday, September 21, 2010
If input X, Y or Z is low, the corresponding diode conducts current, through the 4.7K resistor. Thus there is no current through the diodes connected in series to transistor base . Hence the transistor does not conduct, thus remains in cut-off, and output out is High.
If all the inputs X, Y, Z are driven high, the diodes in series conduct, driving the transistor into saturation. Thus output out is Low.
If all the inputs X, Y, Z are driven high, the diodes in series conduct, driving the transistor into saturation. Thus output out is Low.