Hi --
I made a simple 555 Timer Astable Multivibrator Circuit that pulses every 1 second.
When I run this with two 1.5VDC batteries it works fine.
I made a simple 555 Timer Astable Multivibrator Circuit that pulses every 1 second.
When I run this with two 1.5VDC batteries it works fine.
I wanted to experiment with voltage regulators so I got a UA78M33CKCSE3 (Jameco Datasheet) Voltage regulator. I also had one of those common wall plug power supplies (it says it is 6VDC 300mA). I connected the power supply to the voltage regulator (input and common) and I connected the output to a 22 Ohm resistor (so I expect 3.3VDC 150mA and that is what I see).
Now I use the output (with the 22 Ohm) and common to power my 555 circuit. The result is that pin 3 of the 555 is always 3 volts! If I switch back to my battery it goes 0 - 3 volts over over 2 seconds as expected.
Every where I check the voltage regulator seems fine (it has 3.3 volts and the current is around 150mA).
I must be missing a key idea about using a voltage regulator??? If you can help with any ideas it would be appreciated!
Thank you!
Now I use the output (with the 22 Ohm) and common to power my 555 circuit. The result is that pin 3 of the 555 is always 3 volts! If I switch back to my battery it goes 0 - 3 volts over over 2 seconds as expected.
Every where I check the voltage regulator seems fine (it has 3.3 volts and the current is around 150mA).
I must be missing a key idea about using a voltage regulator??? If you can help with any ideas it would be appreciated!
Thank you!