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Clarification re the No1 pin of the 555 timer

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MDC

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The No1 pin of the 555 timer is referred to as the ground pin. In the context of electrical, I have always associated the term 'ground' to be 'earth'. I have also seen it stated that the No1 pin connects to the negative rail of a breadboard for example. As a newbie, I find that a bit confusing??
 
Ground (or Earth or chassis ground) in an electronics context generally means the reference point or potential, where signals or voltage readings are referenced to. Also usually where any screening or metalwork connects to.

In most modern single-supply devices, power negative is considered 0V and also "ground" or "chassis".
(In early or transistor circuits & occasionally now still, the positive supply is 0V and all voltages are measured negative of that).

With dual-supply devices like some audio amps and opamps etc., that have eg. +15, 0V and -15 power connections, the 0V is normally considered ground.
 
As a newbie, I find that a bit confusing??
That's understandable.
It's unfortunate that "ground" can mean either earth ground or electronic circuit common.
You just have to look at the context to see which meaning applies.
 
Which is why I prefer to refer to the "common" line in electronic supplies as the 0v (Zero Volt) line.
This is the line which is the reference for all voltage measurements.

The 0v line is often, but not always connected to ground/earth.

JimB


Editing...

I am reminded of a cartoon which showed an astronaut on the moon, all dressed up in his space suit and holding the end of a wire in his hand.
The caption read:
"Say Houston, what did you say that we should do with this wire labelled "earth" ?
 
The No1 pin of the 555 timer is referred to as the ground pin. In the context of electrical, I have always associated the term 'ground' to be 'earth'. I have also seen it stated that the No1 pin connects to the negative rail of a breadboard for example. As a newbie, I find that a bit confusing??

Yes...at times it is confusing.
In electronics, you can think of ground as being the supply connection that is always 0v.
If it is meant to be "earth ground", the circuit will usually call it out as such using text, or a different symbol, or both.
 
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