1. Electrical Characteristics Practice Problems 1 Last Mod January 2008  Paul R. Godin with Solutions

2. Calculations Calculate the values for each circuit using values from the specification sheets. Use the TI specification sheets for TTLTI specification sheets for TTL Use the OnSemi Specification sheets for CMOSOnSemi Specification sheets for CMOS Answers at the end of the presentation… elec 7.2

3. Problem #1 Determine the B to C propagation delay for the following circuit: –NAND gate is a 4011B –Point A is a logic Low elec 7.3

4. Problem #2 Determine the propagation delay for the following circuit, assuming the inverter is a 74S04, the NAND gate is a 4093B and the OR is a 7432. elec 7.4

5. Problem #3 Determine the fanout for a 4049UB connecting to 74LS08’s. elec 7.5

6. Problem #4 Determine the fanout for a 7400 connecting to 14584B’s. elec 7.6

7. Problem #5 Determine the noise margin for a 4011B connecting to a 7404. elec 7.7

8. Problem #6 Determine the noise margin for a 7408 connecting to 4050B’s. elec 7.8

9. Problem #7 Determine the Power requirements for a 74LS08 with: –2 gates with a high output –2 gates with a low output elec 7.9

10. Answers… elec 7.10

11. Problem #1 Solution Determine the B to C propagation delay for the following circuit: –NAND gate is a 4011B –Point A is a logic Low t PLH : 250  s t PHL : 250  s t PHL t PLH t PHL The specifications are based on the outputs. Answer is 750ηs elec 7.11

12. Problem #2 Solution Determine the propagation delay for the following circuit, assuming the inverter is a 74S04, the NAND gate is a 4093B and the OR is a 7432. t PLH t PHL t PLH t PLH : 250  s t PHL : 250  s t PLH : 15  s t PHL : 22  s t PLH : 4.5  s t PHL : 5  s Answer is 277ηs elec 7.12

13. Problem #3 Solution Determine the fanout for a 4049UB connecting to 74LS08’s. I OH : 1.25mA I OL : 3.2 mA I IH : 20μA I IL : 0.4mA Answer: Fanout = 8 Gate inputs elec 7.13

14. Problem #4 Solution Determine the fanout for a 7400 connecting to 14584B’s. I OH : 0.4mA I OL : 16mA I IH : 0.1μA I IL : 0.1μA Answer: Fanout = 400 Gate inputs elec 7.14

15. Problem #5 Solution Determine the noise margin for a 4011B connecting to a 7404. 4011B: –V OH : 4.95 V –V OL : 0.05 V 7400: –V IH : 2.0 V –V IL : 0.8V OutputInput Minimum Maximum elec 7.15

16. Problem #6 Solution Determine the noise margin for a 7408 connecting to 4050B’s. V OH : 2.4 V V OL : 0.4 V V IH : 3.5 V V IL : 1.5V OutputInput Minimum Maximum Noise Margin problem! elec 7.16

17. Problem #7 Solution Determine the Power requirements for a 74LS08 with: –2 gates with a high output –2 gates with a low output I CCH : 4.8mA I CCL : 8.8mA elec 7.17

18. END January 2008  Paul R. Godin prgodin @ gmail.com elec 7.18