T3L Logic Circuit Family
Original Publication Date: 1984-Aug-01
Included in the Prior Art Database: 2005-Feb-04
The T3L logic circuit family consists of TTL circuits wherein a double transistor has been added to improve the logic capability of the TTL logic family. The basic T3L circuit is shown in Fig. 1. It comprises double transistor T4, T5 which allows the NAND function of inputs A and B and the AND function of inputs C and D to be performed. Inputs C and D have a threshold which is 200 mV higher than the A and B TTL inputs, and thus are less sensitive to the noise so that these inputs can be connected on long nets on a chip. Based on this basic T3L circuit, the 9 transistors of the cell shown in Fig. 2 may be wired to build various logic circuits. An exclusive-OR circuit is shown in Fig. 3. The cell can also be divided into two independent 3-input NANDs to be used as a two-way multiplexer, as shown in Fig. 4. Fig.