High Power Transistor Packages

Transistor packages usually use the nomenclature TO-xx, where TO stands for Transistor Outline.  There are a number of transistor packages that will handle high power or high current, but it also depends on the semiconductor inside the packages.

A number of different transistor packages have been added over the last month, several can handle higher power loads. One package style is the TO-3 flange mount body. The TO-3 style dissipates a lot of heat because of the large metal package and because the metal flange is normally mounted to an even larger metal plate to dissipate even more heat. The most common TO-3 package holds two leads, with the case acting as the third terminal. Two additional new TO-3 related pages were added; the first a 4-lead TO-3 package, and the second an 8-lead TO-3 package.

Another through hole style high power package is the TO-220, although this one has a metal tab to dissipate heat. The 3 terminal package already resided on the site; however a 5-terminal TO-220 and a 7-Lead TO-220 package were added. The 7-leaded package has staggered leads, and there's an additional 5-Staggered Terminal TO-220 package to compliment it. Either of the new packages are designed to hold more than just a single transistor or FET; operational amplifiers in the case of the TO-3 package or regulators in the case of the TO-220 packages.

The other high power transistor case is the TO-263, or the surface mount version of the TO-220. There's a 3-terminal version, a 5-Terminal TO-263 package and a 7-Terminal TO-263 package.

It's easy to determine the number of pins required for a particular package, normally the function will dictate the number of leads. However it's a bit harder to pick the correct package style. So these are a few of the transistor package styles designed to dissipate high heat on the site.

Issues Realting to How to Derate Transistors and Resulting Failures

There are two main pages in this section of the web site; How to derate Transistors by Temperature [Power x Temperature], and Diode Derating [Current x Temperature]. An interrelated page details how to read and Interpret Temperature Derating Curves, which works for diodes or transistors.

 One of the new pages covers component mounting consideration, as Lead Length vs Thermal Resistance [power dissipation for leaded parts]. This particular topic shows why lead length is an important consideration in component power dissipation [in addition to increased circuit inductance]. A companion page covers Copper Pad Area vs Thermal Resistance, to address surface mount components.

The second new page covers Junction Temperature and Wirebond Life, the bond holding the wire between the semiconductor chip and package lead frame. Wire-Bond failure rate vs junction temperature is another way to cover the same topic as the derating charts already do; However, some derating curves do cover ambient temperature, heat-sink temperature and case temperature, in addition to junction temperature.

Related links include Maximum Safe Operating Area,
Over the last 30 days I have added almost 30 new pages, but they were so inter-related that I didn't think blogging about them would really help. Either each blog posting would read almost the same or they would have had almost no text. So I'll generated a new xml site-map for Google in a few weeks to catch the new pages, or wait until Google reads the pages their linked from. In the mean time I have been adding links to the new pages to the human readable [html] sitemap that covers the site [Engineering Site-Map].

So these are two of the nearly 30 new pages added over the last month. I may add them in a larger posting rather than one posting per new page.

3-Terminal TO-247 Semiconductor Package

Yet another new semiconductor package style added today. This time the component is a 3-Terminal TO-247AC Package. The 'AC' portion of the package type defines the package style depicted on the page. There are other styles of TO-247 components with many more than 3-leads. It's my impression that the TO-247 base number defines a  package with an exposed metal plate on the rear of the component that connects directly to the semiconductor die; however I did not take the time to look that up.

The page graphic shows a package out-line and the dimensions for a TO-247AC and gives the pinout for an FET, but the text also provides the pin out for a transistor package.

As with any other similar package, any type of semiconductor could reside in the body of this case; however only a FET and BJT are given as examples. A few N-Channel FETs that use this package include; 2N7563, 2N7564, and 2N7565 [150 to 320 watts].

As with all new page additions to interfacebus, the page gets a mention in this blog, and to the external Engineering Sitemap. In addition there is always at least one internal link, in this case off the Transistor Packages page.

So every new page addition receives at least three incoming links, with two of the incoming links being external to the web site. However at last check the links on the site-map were 'no-follow', which means there is no credit for the link. The no-follow thing is Google's idea, and I have no control over that. Even if the sitemap does no really provide any search engine ranking it still works as a site-map, which is what it really is.

TO-276 Three-Terminal Surface Mount Package

What is a TO-276 device?
A 3-Terminal Surface Mount Component, shown on; TO-276 Transistor Package.
As discussed on that page the package may be used for any number of different semiconductors, but the term transistor is used in general. As with all the other related packages the TO-276 page is linked off the Transistor Packages page.

There's not much left to say, as this posts relates to the last two previous posts, which have already covered every thing.

This is the first surface mount package added to that section of the web site, all the other pages cover some type of through hole package. However I have had pending data on several other surface mount styles but the data has not been added yet because I been working other site issues ~ I'm not sure if I can add yet another package type in the next few days or not. Of course the Site-Map was also up-dated.

Transistor Die Bonding

Plastic Transistor Body

Following yesterdays posting regarding the addition of the TO-63 transistor package I added yet another transistor package. This newest addition adds a Plastic TO-226 Transistor, very closely related to a Plastic TO-92.

The TO-226 is a common molded plastic case transistor; however because it's a plastic body it's not really used in any government specifications, so there are no BJT Dearting Curves provided as a link. In many cases I add these component bodies and indicate they are transistor devices, but any three terminal part could reside within these component shapes; including FETs and Transistors, or an SCR, Triac, or 3-terminal references or Temperature Sensors.... Of course some of these package will handle more power than others and may not accommodate higher current or voltage applications. Here is the top level page linking all Transistor Packages.

Both the new page on the TO-226 device and the TO-63 device added yesterday have been included in the Engineering SiteMap.

As normal with many new pages, this one is a copy of a preexisting page on the Engineering Site. However over time I'll add more data as I get back to that topic. The page on the TO-63 started out with a bit more data. I should be adding another related page on Friday.

TO-63 Transistor Package

I just added a page showing the TO-63 Package Style. I'm not really sure how it was missing, because the drawing was being used on a few pages. As normal it's a copy of another page [TO-61 Case], but with a different graphic. Next time I get to it I'll add some data to the page.

The main page that shows a number of different links for; Transistor Cases.

Many of the pages that also use or point to the pages describing transistor packages is the How to Derate Transistors.

In general I indicate that this is a transistor package, but any three terminal device could reside in the package.

The graphic is a B-52 Control Panel, lower deck. 
Much of the gear does not look like it fits, like it's a mix of different up-grades over the years.

Transistor Array Packages

I added a new page showing a few different types of Transistor Arrays. It's linked off the dictionary page for Array.

Here are a few related pages which only received a few page views this year:
How to derate a 2N3967 transistor.
How to derate a 2N2432 transistor.
How to derate a 2N2604 Transistor.
2N6758 Field Effect Transistor derating.
TO-66 Transistor Package.
Device Under Test definition.
In fact many of the pages that received less that a few dozen hits over the entire year relate to Transistor Derating. But it's hard to make a page on a part number, try searching for a part number and you get hundreds of computer generated pages with rows of part numbers.

Semiconductor Case Drawings

Added a few new pages covering transistor package styles.
This series of pages really don't generate any incoming hits, but I already had the data so why not just add the pages. Plus its been awhile with out adding any new pages.

The first covers a TO-18 Transistor package.
The second page covers a TO-92 Transistor package.
A third page covering a TO-204 Transistor.
A final page covering the TO-220 Style Package.

The graphics used on these page were already being used on some other page on the web site. So the only new thing that was added today was four new web pages, but the data was already on the site at a different page. However these new additions do round out the main package style page.

At any rate this posting shows the 3 new pages and provides an external site that links to them, I can't really help that they may never see any visitors.

Rules for Derating a Transistor

Following yesterdays transistor posting, I've added two more pages relating to how to derate a particular transistor. Like the previous post the new transistor pages are near a copy of a preexisting page, that happened to use the same derating graph.

MIL-PRF-19500/539D:

2N6301 Temperature-Power Derating Curve [NPN BJT].

2N6300 Temperature-Power Derating Curve [NPN BJT].

MIL-PRF-19500/545G:

2N5153 Temperature-Power Derating Curve [PNP BJT].

2N5151 Temperature-Power Derating Curve [PNP BJT].

Three other page up-dates then followed;

How to Derate Transistors.

How to Derate NPN Transistors.

How to Derate PNP Transistors.

Which were updated to hold the links to the new pages. In addition each new page links to it's copy that holds the same MIL Spec and Derating Graph.

Also added a new line item to the Transistor Derating Recommendations page, which only provide Derating Equations with no Derating Curves.

It may of taken over a hour to generate the page up-dates but it was an easy way to generate two new pages and add more page to page links.In addition four other related pages were updated:

MIL-PRF-19500/396K;

2N3764 Temperature Derating Graph.

2N3765 Temperature Derating Graph.

MIL-PRF-19500/396K;

2N3762 Temperature Derating Graph.

2N3762U4 Temperature Derating Graph.

So in this derating sections there were 10 page up-dates and 2 new page additions. There were also another dozen unrelated page updates.

Guidelines to Component Derating.

Transistor Derating Guide Lines

Added a new page to cover power derating of a 2N3765 transistor. The page is almost a copy of the page for the 2N3764 transistor because they both use the same derating graph. Links have been added to their related transistors covered by the same specifications; 2N3762U4 transistor and 2N3762UA transistor, both surface mount devices. A reference was also added to the page covering PNP transistor curves, and derating transistors.

A few other unrelated pages were also up-dated, including;

Derating a 2N930.

Derating a surface mount 2N930UB.

2N718 derating graph.

2N1613 derating curves.

2N3055 transistor derating curves.

All the pages provide a Temperature-Power Derating Curve, and some also provide a derating equation. Use one or the other as a guideline for derating the device.

Related pages;

Recommendation on how to Derate a Transistor.

Derate a BJT by Temperature.

FET Derating Guidelines.

NPN Transistor Derating Curve.

Power Derating for Transistors.

Recommendation on how to Derate a Transistor

Starting with the long list of Transistor Derating Curves, I added in several transistor links to Transistor Derating Guidelines [which is the new page]. Or, recommendations on how to derate a transistor based on a linear equation, with no graphic [Derating Curve].

The new transistor links pick up missing devices in the list, but because I didn't have a derating chart they all point to the new page which provides the derating recommendation for each of the devices. The recommendation for each transistor is how much to decrease power dissipation over increasing temperature, mW/C [and that's all].

Two of the main links off the transistor derating page are NPN Derating Curves, and PNP Derating Curves, but I don't have any plans to add the new links to either of those pages.

Individual transistor pages not yet listed in the blog;
2N3250 Derating Curve.
2N3467 Derating Curve.
2N3485 Derating Curve.
2N3634 Derating Curve.
2N3740 Derating Curve.

A related list; How to derate FETs.
2N6764 Derating Curve.
2N6766 Derating Curve.
2N6768 Derating Curve.

How to Derate a Component.
Site Home page; Computer Bus pin Outs.

Derate a BJT by Temperature

I've posted about adding some pages covering transistor derating, but I never really linked any of the new pages here. I don't have any new pages to blog about, so I'll list a few of the pages covering transistor derating.

These are just a random sampling of a few pages;
2N2484 PNP Transistor.
2N2906 NPN Transistor.
2N3743 PNP Transistor.
2N4029 PNP Transistor.
2N6676 NPN Transistor.

There's nothing special about these pages, in fact a few seemed to be some of the smaller pages in the group. But they each point to other pages with the same or similar device in a different package style. So I'm really pointing to a dozen pages while only listing 5 here.

These pages were added around the first of December, and up-dated once to add more data. Looks like a few could still use some more data, but I'll be up-dating the pages that haven't changed yet.

NPN Transistor Derating Curve

In addition to adding more pages covering Transistor Derating Guidelines, two new pages were added to subdivide the listing.

One page covers NPN Transistor Derating Guidelines, while another page covers PNP Transistor Derating Guidelines. The new pages show each transistor link shown in a derating chart, even if the link points to a simular page already listed. One Temperature-Power Derating Curve may cover more than one transistor.