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Mimimum base current for 2N3055

Started by Unknown February 15, 2013
Could some electronics guru please help ?
What is the minimum base current for the
2N3055 ? The On Semi data sheet that I 
downloaded is not very helpful. Thanks in 
advance for your help.
<dakupoto@gmail.com>
> > Could some electronics guru please help ? > What is the minimum base current for the > 2N3055 ? The On Semi data sheet that I > downloaded is not very helpful.
** You Q makes no sense. Some context is ESSENTIAL !! .... Phil
On Thu, 14 Feb 2013 23:25:39 -0800 (PST), dakupoto@gmail.com wrote:

>Could some electronics guru please help ? >What is the minimum base current for the >2N3055 ?
--- That depends on what you want to do. -- JF
On Feb 15, 2:25=A0am, dakup...@gmail.com wrote:
> Could some electronics guru please help ? > What is the minimum base current for the > 2N3055 ? The On Semi data sheet that I > downloaded is not very helpful. Thanks in > advance for your help.
Minimum base current? You can probably feed it 10nA and get ~1uA from the collector... but that would be a pretty silly thing to do. If you're looking at the same data sheet I down loaded then figure 2 shows typical current gain vs collecter current. (divide Ic by hfe and you have an estimate of the base current you'll need.) Unless you want to saturate the thing... then figure 3 is your friend. As Phil and JF said, more context is needed if you want more specific advice. George H.
On Thu, 14 Feb 2013 23:25:39 -0800, dakupoto wrote:

> Could some electronics guru please help ? > What is the minimum base current for the 2N3055 ? The On Semi data sheet > that I downloaded is not very helpful. Thanks in advance for your help.
Zero. Just leave the base disconnected. If this answer frustrates you, re-read your question and ask yourself what other answer could be given. -- Tim Wescott Control system and signal processing consulting www.wescottdesign.com
"Tim Wescott" <tim@seemywebsite.please> wrote in message 
news:5rqdnT9-OYavzoPMnZ2dnUVZ_sudnZ2d@giganews.com...
>> What is the minimum base current for the 2N3055 ? > > Zero. Just leave the base disconnected.
Or if you mean direction, not just magnitude, then you can probably sink five or ten amperes out of it ("IB2 = -5A" or whatever), during reverse recovery of the B-E junction. It'll only last a couple microseconds though. Tim -- Deep Friar: a very philosophical monk. Website: http://seventransistorlabs.com
On Fri, 15 Feb 2013 05:48:08 -0800 (PST), George Herold
<gherold@teachspin.com> wrote:

>On Feb 15, 2:25&#2013266080;am, dakup...@gmail.com wrote: >> Could some electronics guru please help ? >> What is the minimum base current for the >> 2N3055 ? The On Semi data sheet that I >> downloaded is not very helpful. Thanks in >> advance for your help. > >Minimum base current? You can probably feed it 10nA and get ~1uA from >the collector... but that would be a pretty silly thing to do.
You could feed it a negative current too.. minimum current to damage the E-B junction? Minimum current to burn off the bonding wire?
>If you're looking at the same data sheet I down loaded then figure 2 >shows typical current gain vs collecter current. (divide Ic by hfe >and you have an estimate of the base current you'll need.) Unless you >want to saturate the thing... then figure 3 is your friend. > >As Phil and JF said, more context is needed if you want more specific >advice. > >George H.
Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> writes:

> On Fri, 15 Feb 2013 05:48:08 -0800 (PST), George Herold > <gherold@teachspin.com> wrote: > >>On Feb 15, 2:25&nbsp;am, dakup...@gmail.com wrote: >>> Could some electronics guru please help ? >>> What is the minimum base current for the >>> 2N3055 ? The On Semi data sheet that I >>> downloaded is not very helpful. Thanks in >>> advance for your help. >> >>Minimum base current? You can probably feed it 10nA and get ~1uA from >>the collector... but that would be a pretty silly thing to do. > > You could feed it a negative current too.. minimum current to damage > the E-B junction? Minimum current to burn off the bonding wire?
Yes I was torn between "zero" and some negative damage threshold. I thought I saw something about 2N3055 being good for a low noise amplifier, which sounds ridiculous but could be related... [...] -- John Devereux
On Thursday, February 14, 2013 11:25:39 PM UTC-8, daku...@gmail.com wrote:
 
> What is the minimum base current for the > 2N3055 ? The On Semi data sheet that I > downloaded is not very helpful.
It's not a switching device, so the current into the base has a 'minimum' only in the sense that a hot device under bias leaks from the collector. So, to reliably turn OFF the transistor, you might need to sink 200 mA/beta at 25 C, 60Vce (that's circa 2 mA). The specs on beta (also known as h_fe) are, of course, very loose; 20 to 70 at 4A, and there's temperature and collector-current variations in the charts. My source here is the RCA file #145, dated August 1966 (that's the most complete data sheet I know of for this part).
On Fri, 15 Feb 2013 18:05:48 +0000, John Devereux
<john@devereux.me.uk> wrote:

>Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat> writes: > >> On Fri, 15 Feb 2013 05:48:08 -0800 (PST), George Herold >> <gherold@teachspin.com> wrote: >> >>>On Feb 15, 2:25&#2013266080;am, dakup...@gmail.com wrote: >>>> Could some electronics guru please help ? >>>> What is the minimum base current for the >>>> 2N3055 ? The On Semi data sheet that I >>>> downloaded is not very helpful. Thanks in >>>> advance for your help. >>> >>>Minimum base current? You can probably feed it 10nA and get ~1uA from >>>the collector... but that would be a pretty silly thing to do. >> >> You could feed it a negative current too.. minimum current to damage >> the E-B junction? Minimum current to burn off the bonding wire? > >Yes I was torn between "zero" and some negative damage threshold. > >I thought I saw something about 2N3055 being good for a low noise >amplifier, which sounds ridiculous but could be related... > >[...]
Large power devices, particularly those with star or Christmas tree layouts, have low rbm, thus low noise. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.