Another question resulting from too much time on my hands. Why do we
have rectifier diodes (e.g. 1N4xxx, 1N54xx) with different voltage
ratings? Other than the voltage rating I don't see any differences on
the data sheets I've looked at. Why not just make and use 1kv diodes
alone?

73,
Mike, KK6GM

Lower voltage rectifiers are easier to make and therefore cheaper. Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.

the funnie this is that the $$$ diference is not seen at the costumers end.

do you realy care the the diode is 3 Cents more (making a 100$ project)from
the low votalge one.......(some stores some cases)

73's


--
http://www.qsl.net/sv1hao
"Bob" wrote in message
...
Lower voltage rectifiers are easier to make and therefore cheaper.
Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.

the funnie this is that the $$$ diference is not seen at the costumers end.

do you realy care the the diode is 3 Cents more (making a 100$ project)from
the low votalge one.......(some stores some cases)

You might be surprised.

In fact, cost reduction is a *big* issue in the manufacture of many
(most?) consumer electronic products.

Look at it this way: if you save three cents on a single part, of
which only one is used in a $100 device... and you manufacture a
million of these devices per year... then you've saved $30,000 per
year. That's not chump-change.

If you can save $.03 per part, and you use ten of these parts per
device, and you manufacture a million units per year - then you've
just saved $300,000, which will cover the cost (salary and overhead)
of at least one good engineer.

Yes, my friend, big electronics companies _do_ care - a lot - about
shaving the pennies out of the bill-of-materials cost of the devices
they manufacture.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

the funnie this is that the $$$ diference is not seen at the costumers end.

do you realy care the the diode is 3 Cents more (making a 100$ project)from
the low votalge one.......(some stores some cases)

You might be surprised.

In fact, cost reduction is a *big* issue in the manufacture of many
(most?) consumer electronic products.

Look at it this way: if you save three cents on a single part, of
which only one is used in a $100 device... and you manufacture a
million of these devices per year... then you've saved $30,000 per
year. That's not chump-change.

If you can save $.03 per part, and you use ten of these parts per
device, and you manufacture a million units per year - then you've
just saved $300,000, which will cover the cost (salary and overhead)
of at least one good engineer.

Yes, my friend, big electronics companies _do_ care - a lot - about
shaving the pennies out of the bill-of-materials cost of the devices
they manufacture.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

the funnie this is that the $$$ diference is not seen at the costumers end.

do you realy care the the diode is 3 Cents more (making a 100$ project)from
the low votalge one.......(some stores some cases)

73's


--
http://www.qsl.net/sv1hao
"Bob" wrote in message
...
Lower voltage rectifiers are easier to make and therefore cheaper.
Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.

On Wed, 3 Sep 2003 10:39:33 -0700, "Bob"
wrote:

Lower voltage rectifiers are easier to make and therefore cheaper. Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.

While the 1 kV 1N4007 is definitely a different creature (with some
PIN diode characteristics) compared to the lower voltage 1N4001-1N4006
rectifiers, I very much doubt that they make separate wafers for
1N4001, 1N4002 etc. but instead try to make, say a 500 V rectifier.

My guess is that they just measure the reverse leakage voltage at
various voltages and print a different label, based on these
measurements. Those passing only the 50 V test will be labelled 1N4001
and sold at a slightly lower price and so on.

If there is a huge order for 1N4001 and there is not enough 50 V units
produced, some units tested OK for 100-500 V are labelled 1N4001 to
full fill the large order. Thus, some selected 1N4001 parts may work
even above 100 V.

Paul OH3LWR

On Wed, 3 Sep 2003 10:39:33 -0700, "Bob"
wrote:

Lower voltage rectifiers are easier to make and therefore cheaper. Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.

While the 1 kV 1N4007 is definitely a different creature (with some
PIN diode characteristics) compared to the lower voltage 1N4001-1N4006
rectifiers, I very much doubt that they make separate wafers for
1N4001, 1N4002 etc. but instead try to make, say a 500 V rectifier.

My guess is that they just measure the reverse leakage voltage at
various voltages and print a different label, based on these
measurements. Those passing only the 50 V test will be labelled 1N4001
and sold at a slightly lower price and so on.

If there is a huge order for 1N4001 and there is not enough 50 V units
produced, some units tested OK for 100-500 V are labelled 1N4001 to
full fill the large order. Thus, some selected 1N4001 parts may work
even above 100 V.

Paul OH3LWR

Lower voltage rectifiers are easier to make and therefore cheaper. Further,
they have lower forward drop and are faster. No point in using too high a
rating if these other factors are worth considering.