I need to add a diode to each of my signals to allow current to only flow in one direction. In the past, I have bought diodes at Radio Shack, 1N4001 through 1N4004, depending upon which were currently in stock. The package simply referred to them as “diodes”. Now, however, some packages refer to them as “silicone diodes”. Other packages refer to them as “rectifier diodes”. Is this all one and the same or are silicone diodes different than rectifier diodes?
Rich
rectifier diodes -should- be the same as silicone diodes …
unless they say ‘tunnel’ or ‘zener’ anyways
Diodes have a voltage and current rating. A normal Google search using the diode number will bring up a data sheet.
I normally go with a 1N4001 for 1 amp at up to 100 volts. About 30¢ State side, 9¢ China.
For LED operation I use 1N914, 300ma at up to 50 volts. About 10¢ State side 2¢ China.
If you need a higher voltage or current rating, inter the current needed then browse for the needed voltage.
Rather than use 4 diodes to make a 1 amp bridge rectifier I buy the DB-107 four pin DIP chip. About 50¢ US, 20¢ China.
Mel
Most generic diodes are made from silicon.
“Rectifier” it just means that its typical application is for rectifiers, but all generic diodes are rectifier diodes.
What is important is the PIV and maximum current. PIV is peak inverse voltage, specifying how much reverse voltage it can handle before failure. The diodes you bought have a PIV ranging from 50V up, so those diodes are more than adequate for your purposes.
The 1N914 type are fine for LEDs, since they can handle more than 10x the limit of an LED - the LED will pop long before the current dmaages the diode. They are also fine fooor controlling power to Tortoise switch machines, since those only draw about 18ma.
To rectify DCC, for installing a lighting circuit in a passenger car for example, it is recommended to use the 1N5400 series diodes - they can better handle the high speed switching of the power. The 1N4000 series are fine to rectify a 60Hz AC into DC, but DCC is a much higher frequency.
1N5400 series are rated for 3 amps. The last digit indicates the maximum reverse voltage it can stand. 0 = 50V, 1 = 100V, 2 = 200V, 4 = 400V, etc.
1N4000 series are rated for 1 amp, the last digit again indicates the maximum reverse voltage, but it’s not the same as the 1N5400. On the 1N4000 series, 1 = 50V, 2 = 100V, 3 = 200V, 4 = 400V.
Reverse voltage is the voltage across the didoe when the polarity is such that current does not flow through the diode. Most LEDs have a relatively low reverse voltage rating, which is why it is usually recommended to put to of them anti-parallel when used with DCC, which means the highest reverse voltage one LED will see is the forward voltage of the one that happens to be lighting up. Or use a standard diode if you don’t need two LEDs.
–Randy
Thanks, guys. I appreciate the information.
Rich
They are different but the differences are irrelevant to your application.
Regards
Walid