IRF 350

[Mike]

Does anybody know who makes the IRF350 mosfet? Please reply with the web site. <p>Thank You, Mike

[scm6079]

Chances are reasonable that if it is an LCD or LED display, it is a standard unit, controlled via serial. I can't help with the EQ, but perhaps if you do a search for the display part number you can get the data sheet for the display, and independently test that component.<p>-Scott

[rshayes]

Once upon a time, the IRF350 was made by International Rectifier, as you might guess from the IRF prefix. It was housed in a TO-3 type (actually TO-204) metal case. Somewhere around 1995, International Rectifier discontinued most of its products that were in metal cases. The only exceptions that I know of were parts in a special metal case that was about the size of the plastic TO-220 case. These were ridiculously expensive, and may have been intended for space or other high reliability applications. All of the other metal cased parts appear to have been discontinued.<p>At one time, the IRF350 was also second sourced by RCA. Since then, the RCA semiconductor operations were sold to General Electric, which combined them with the General Electric semiconductor operations and with Intersil. These combined operations were then sold to Harris Semiconductor, which now markets some products under the Harris name and others under the Intersil name.

[russlk]

The modern version is IRFP350 in the TO-247AC case. You may be able to bolt it in the TO3 hole and put the leads in the holes the TO3 used.<p>The IRF350 is also know as JANTX2N6768, if you want to look for the TO3 case. It will no doubt be expensive if you find it.<p>[ August 10, 2003: Message edited by: Russ Kincaid ]</p>

[bodgy]

<MOAN MODE ON><p>I'm sorry Mike, but did you actually click on the INTERNATIONAL RECTIFIER link I provided?<p>There you will see that you can order samples or purchase small quantities of the IRF350 in 204AE package.
<MOAN MODE OFF><p>I haven't checked but do Digikey or Mouser stock them?<p>Future do, PioneerUS do, RSComponents (not sure about the US offshoot) and Farnell do.<p>Colin

[Mike]

Bodgy,<p>I clicked on the link. There is no button to order samples, and when I clicked on add to cart, then clicked on the page to check prices, and it came up with error or something like it.<p>-Mike

[bodgy]

<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by mikea1962375:
Bodgy,<p>I clicked on the link. There is no button to order samples, and when I clicked on add to cart, then clicked on the page to check prices, and it came up with error or something like it.<p>-Mike<hr></blockquote><p>Mike,<p>The webpage appears to be slow, but it isn't!<p>Click on the ADD to CART button and wait for it to turn RED - yes I know they just expect you to know this. Once it is red, you can then click on the VIEW BASKET button. Up the top will be some index ears like a set of filing folders, click on the CHECK AVAILABILTY folder and up will come the price and availability. <p>I'm registered with them, I'm not sure whether you have to register to order. IRF charge for samples, though if you order is likley to be big enough and you know an account Rep, that may be different.
Anyhow the price is shown below from their order page in US$'s<p>IRFP350
10-Aug-2003 $3.83 <p>Colin<p>Colin<p>[ August 11, 2003: Message edited by: bodgy ]</p>

[rshayes]

The IRF350 may be a very old part. I think we may have used it in a power supply design around 1980. At that time, the price was about $80. <p>I would suggest using a plastic part. It is my understanding that around 1996 or 1997 that military designs were no longer required to use Mil-spec parts. I think that this may have been why the metal parts were abruptly discontinued.<p>A JANTX part is one made to the requirements of MIL-S-19500, and the X indicates an X-Ray inspection after assembly. The production facility had to be inspected and approved, and there may have been a requirement that the parts be "burned-in" and retested. All of this raises the cost considerably. If the part is out of production, the cost can go even higher.<p>I would look at other parts than the IRF350. There have been thousands of devices introduced since then, and some of these may work better at lower cost. If you don't really need a 400 volt device, use a 300 volt or 200 volt device. The die area for constant on resistance with increasing voltage used to approximate a square law, and the component cost tended to follow the die area. This made high voltage parts disproportionately expensive. A large area device will also have higher gate to drain capacitance and be harder to drive.

[Mike]

Can anybody suggest a replacement that would do the same job, or better but also cheaper? Project is at:<p>http://sound.westhost.com/project83.htm<p>-Mike

[russlk]

The lowest cost device I found was IRFZ24 at Digi-Key for $0.94 in TO-220 package.