Assignment Help >> Electrical Engineering
Consider the modified Schottky TTL NAND gate shown in Figure. The current gain of all transistors is β = 20.
(a) Assume v_{X} = v_{Y} = v_{Z} = logic 1 and assume two similar type load circuits are connected to the output. The transistor Q_{2} is biased in saturation with i_{B2} = 0.1 mA and i_{C2} = 0.2 mA. Determine the values of R_{B1} and R_{C1}.
(b) Using the results of part (a), and assuming v_{X} = 0.4 V and v_{Y }= v_{Z} = 1.8 V, determine v_{B1}, v_{B2}, v_{O} , and all base and collector currents. Assume two similar type load circuits are connected to the output.
(c) Assume v_{X} = v_{Y} = v_{Z} = logic 1 and assume four similar type load circuits are connected to the output. Using the results of part (a), determine v_{B1}, v_{B2}, v_{O} , and all base and collector currents.
(d) Determine the maximum fanout for a low output state.