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David lopez
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I am trying to use the 74ls90. It won't change it's output. It suppose to count to 9. The input
Pulses come from a 555 timer.
Pulses come from a 555 timer.
Again, as in your previous thread ... I will ask for your circuit and photo of your constructionDavid lopez said:A higher voltage does not seem to be
Working.
Ohh and since you didn't seem to get your timer circuit working properlyDavid lopez said:The input
Pulses come from a 555 timer.
Agreed. @David lopez -- does your circuit look like this?davenn said:Again, as in your previous thread ... I will ask for your circuit and photo of your construction
The 74LS90 is a type of integrated circuit (IC) that is used to count pulses. It has four separate counting sections, each of which can count up to 9 pulses. The IC works by receiving input pulses and using them to trigger a series of flip-flops, which in turn change the output values.
First, check all connections and make sure they are secure. Then, verify that the input pulses from the 555 timer are reaching the 74LS90. If they are, check for any loose or damaged components on the IC. You can also try replacing the IC with a new one to see if that resolves the issue.
There are a few potential reasons for this. First, make sure that the input pulses from the 555 timer are at the correct voltage and frequency. Additionally, check that the power supply to the IC is stable and within the recommended range. If these factors are not the issue, there may be a problem with the IC itself.
Yes, the 74LS90 can accept a wide range of input pulses, including square waves, sine waves, and triangular waves. Just make sure that the pulses are within the recommended voltage and frequency ranges for the IC.
To improve accuracy, you can use a higher frequency input signal, as this will result in more pulses being counted in a given time period. Additionally, you can use a more stable power supply and ensure that the IC is not overheating. Finally, double-check all connections and components to ensure they are functioning properly.