To answer a question often asked, how much voltage at what current can I get out of a logic gate? Well here's some answers. Rated values from the data sheet are quickly exceeded. Needless to say life expectancy beyond rated levels can't be predicted.
Inverters were used but the results might be the same for other normal output gates. Drivers were not done. Maybe next time I will get odd family members.
Outputs were tested at various loads. For high out the load was put between VCC and the output. For low out the load was put between the output and VCC. Measurements were taken quickly.
No smoke was released during any of these exercises. There is still the question of how long the output could be driven at these levels.
What level of pull up resistor is needed for what chips? In order for the input to see a valid high, just about any resistor will do. Less than 50K for 74xx, or 1M for CMOS. So put away your calculators on that question. Just about anything works.
Inverters were used but the results might be the same for other normal output gates. Drivers were not done. Maybe next time I will get odd family members.
Outputs were tested at various loads. For high out the load was put between VCC and the output. For low out the load was put between the output and VCC. Measurements were taken quickly.
No smoke was released during any of these exercises. There is still the question of how long the output could be driven at these levels.
What level of pull up resistor is needed for what chips? In order for the input to see a valid high, just about any resistor will do. Less than 50K for 74xx, or 1M for CMOS. So put away your calculators on that question. Just about anything works.
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