Hi guys,
I came across the following npn transistor circuit in a coffee grinder. The led D1 is the led of a MOC3063. It looks kind of peculiar to me as normally the 'load' this case the led and the resistor would be normally placed on the collector side and I haven't seen the collector tied to ground with these kind of setup before.
Something else I noticed was this - the supply voltage is 5.1V (comes from a 5.1V Zener regulator). But measured from the Cathode to ground of D1 the meter shows around 5.6V how can this be?
This unit works which means the circuit works, Ltspice simulation also does work apart from the 5.6V measurement. Why might have the designer choose this particular order, might there be an advantage to this approach? Hoping for some more interesting thoughts.
Thanks in advance for the help.
p.s: I have searched the internet for a similar circuit but didn't get anything identical to this.
I came across the following npn transistor circuit in a coffee grinder. The led D1 is the led of a MOC3063. It looks kind of peculiar to me as normally the 'load' this case the led and the resistor would be normally placed on the collector side and I haven't seen the collector tied to ground with these kind of setup before.
Something else I noticed was this - the supply voltage is 5.1V (comes from a 5.1V Zener regulator). But measured from the Cathode to ground of D1 the meter shows around 5.6V how can this be?
This unit works which means the circuit works, Ltspice simulation also does work apart from the 5.6V measurement. Why might have the designer choose this particular order, might there be an advantage to this approach? Hoping for some more interesting thoughts.
Thanks in advance for the help.
p.s: I have searched the internet for a similar circuit but didn't get anything identical to this.
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