1N914/1N4148 a good rectifier?

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Voltage drop is high. If you consider low power of 100 mA max or so then OK. It's classified as a high spped switching diode with general applications.

The UF4001 is high surge, high current, high reliability and low voltage drop. Musch more suitable for power supply applications.
 
Indeed 1N4148 are very smart diodes for low-power low-voltage high-speed applications because you can almost completely forget about reverse recovery and junction capacitance when you use them (not to mention that you can get a thousand of them for very little money). Of course, you can use 1N4148 as power supply rectifiers, but consider the absolute maximum ratings (100V blocking, 2A peak and 300mA average) and some more realistic long-term ratings (75V blocking, 1A peak, 150mA average).
 
Eva said:
Indeed 1N4148 are very smart diodes for low-power low-voltage high-speed applications because you can almost completely forget about reverse recovery and junction capacitance when you use them (not to mention that you can get a thousand of them for very little money). Of course, you can use 1N4148 as power supply rectifiers, but consider the absolute maximum ratings (100V blocking, 2A peak and 300mA average) and some more realistic long-term ratings (75V blocking, 1A peak, 150mA average).


1N4148.
They are perfectly alright to use for smaller currents rectification.

Say you want to supply a couple of Op-Amps.
Usually they do not take more than 5-10 mA supply per device.
And maybe max output current from Op-amp is like 5-10 mA.

Two Op-amps, even at max output, will not often take more than 50mA.
This is a case where is no problem using 1N4148.
As well as for other applications, where you use lower currents.


lineup
 
awpagan said:
opamps?

How about power supplies for Dac's?
eg, the flea?
Headphone amp's might be borderline?


As told above in a post,
the VF voltage drop of 1N4148 is higher than for example 1N4001.
Maybe 0.7V already at 5 mA.

A better alternative, to have lower VF, are Schottky Diodes.
There are many different.
They can often not be used to rectify higher Voltages.
But some can take 40-50 Volt.

The voltage drop is low.
For example much used is:
1N5819 .... 1.0 Ampere Schottky Barrier Rectifiers
http://www.ee.washington.edu/stores/DataSheets/diodes/1n5819.pdf

For lower currents, you have BAT81, 82, 83, 85, BAT86 Schottky
 
Don't forget about the filtering capacitors. When you turn on your powersupply, the capacitors are "empty", if you want to charge them fast (so you can reach nominal output voltage fast of the PSU), then the 1N4148 can blow.
I have seen somewere a preamplifier, where the PSU was made of thousands uF capacitor, but there were only 2-3 op.amps....
 
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