Diode Transistor Logic
The following section explains in detail about the Diode Transistor logic.
Diode Transistor Logic:
- In DTL (Diode transistor logic), all the logic is implemented using diodes and transistors. A basic circuit in the DTL logic family is as shown in the figure below.
- Each input is associated with one diode.
- The diodes and the 4.7K resistor form an AND gate. 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.