- #1
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Homework Help Overview
The discussion revolves around understanding the operation of a 555 timer circuit, particularly its output behavior in response to input signals. Participants are exploring the properties and functionality of the 555 timer in a circuit context.
Discussion Character
- Exploratory, Conceptual clarification, Assumption checking
Approaches and Questions Raised
- Participants are attempting to clarify the output states of the 555 timer under different input conditions, questioning what happens with no input signal and the effects of negative-going input edges. There is also discussion about the implications of repeated input pulses and the role of internal components like the transistor.
Discussion Status
The discussion is ongoing, with participants sharing their thoughts and uncertainties about the 555 timer's behavior. Some guidance has been offered regarding the importance of understanding the internal block diagram and the suggestion to research "555 missing pulse" for further clarity.
Contextual Notes
Participants express uncertainty about their understanding of the 555 timer's operation, indicating a need for further exploration of its properties and behavior in different scenarios.
- #2
gneill
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I'm not sure what your appropriate attempt at a solution is 
- #3
maherelharake
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Haha yeah sorry it seems as if I didn't even think about it.
Well I know that 555's have properties such as:
low trigger input leads to high output
high trigger input leads to low output
it outputs a square wave
if the trigger isn't a max/min then there is no output
Not sure if these ideas are leading me up the correct path.
Well I know that 555's have properties such as:
low trigger input leads to high output
high trigger input leads to low output
it outputs a square wave
if the trigger isn't a max/min then there is no output
Not sure if these ideas are leading me up the correct path.
- #4
gneill
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You need to figure out what the state of the 555 would be (that is, the output) if there were no input signal. Then what happens when a negative going input edge occurs (say just one negative going pulse). The internal block diagram for the 555 might help.
What will be the result of repeated input pulses? What's the transistor across the timing capacitor going to do?
What will be the result of repeated input pulses? What's the transistor across the timing capacitor going to do?
- #5
maherelharake
- 261
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Well based off my previous statements, would no input signal lead to a high output?
I don't know what would happen if an input edge occurs.
Wouldn't repeated input pulses just give repeated outputs?
I also don't know what the transistor would do
I'm not that great at this stuff
I don't know what would happen if an input edge occurs.
Wouldn't repeated input pulses just give repeated outputs?
I also don't know what the transistor would do
I'm not that great at this stuff
- #6
gneill
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Do a google search on "555 missing pulse". You should turn up a circuit operation description. But you should really try to understand the block diagram of the 555 so that the operation is clear. The 555 is composed of some pretty simple functions that are just wired together in a clever way, and allow the 555 to behave in some very useful ways with just small changes in external wiring.