Hi,
New to this forum, but the article says to notify you of any errors we catch. So here I am...
In the Zener Diodes article, mid way through there is a discussion of adding a load to the circuit and calculating the current, etc. More importantly, finding out if the zener is even turned on looking at the R-dropping resistor.
At the end of the calculations box figuring out (using Ohm's law) what the minimum R-dropping resistor should be is a paragraph described below:
"Thus, if the load resistance is exactly 38.889 kΩ, there will be 12.6 volts across it, diode or no diode. Any load resistance smaller than 38.889 kΩ will result in a load voltage less than 12.6 volts, diode or no diode. With the diode in place, the load voltage will be regulated to a maximum of 12.6 volts for any load resistance greater than 38.889 kΩ."
okay, a couple of words are reversed - Any load resistance 'smaller' - should be 'greater'. (as the example of 100K proves). Like wise - the last line ....for any load resistance 'greater' - should be 'smaller' to keep the 12.6 volts.
Hope this helps.
New to this forum, but the article says to notify you of any errors we catch. So here I am...
In the Zener Diodes article, mid way through there is a discussion of adding a load to the circuit and calculating the current, etc. More importantly, finding out if the zener is even turned on looking at the R-dropping resistor.
At the end of the calculations box figuring out (using Ohm's law) what the minimum R-dropping resistor should be is a paragraph described below:
"Thus, if the load resistance is exactly 38.889 kΩ, there will be 12.6 volts across it, diode or no diode. Any load resistance smaller than 38.889 kΩ will result in a load voltage less than 12.6 volts, diode or no diode. With the diode in place, the load voltage will be regulated to a maximum of 12.6 volts for any load resistance greater than 38.889 kΩ."
okay, a couple of words are reversed - Any load resistance 'smaller' - should be 'greater'. (as the example of 100K proves). Like wise - the last line ....for any load resistance 'greater' - should be 'smaller' to keep the 12.6 volts.
Hope this helps.