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RE: find part number from device marking code

michaelkellett — Mon, 11 Nov 2024 14:52:34 GMT

Do you know who made it ?

(Because you have asked in a section of the E14 site for On Semi)

You can look this up for yourself - there are several websites (non of them cover everything).

As you can see - it might be a BSR175, but it might not.

So now you need to work out what its connected to and what it might be doing !

find part number from device marking code

almightyTech — Mon, 11 Nov 2024 12:54:48 GMT

its three terminal smd transistor marked as "LP"
please share full part number.

RE: find part number from device marking code

jc2048 — Mon, 11 Nov 2024 14:35:06 GMT

BSR175?

RE: Ezairo R7111

beacon_dave — Fri, 30 Jun 2023 12:15:27 GMT

Mouser appear to list it but not stock it, so it's 'call for quote'.

Ezairo R7111

davidchiu — Fri, 30 Jun 2023 07:50:32 GMT

Hi,

I am working on a personal hearing device and am looking for a chip made by Onsemi called Ezairo 7111. My project is in the development / prototyping stage so I need only a few pieces. So far I tried Digi Key and RS Components but they do not carry this chip.

Do you or anyone knows where I can buy or get samples ?

Thanking you in advance

David Chiu

RE: Ezairo R7111

michaelkellett — Fri, 30 Jun 2023 09:22:34 GMT

Onsemi don't list any inventory anywhere.

I think your only hope is to contact them directly, or maybe through a franchised distributor.

You might have trouble getting them to talk to you unless you are working in a business or academic setting.

RE: Transistor Amp

D_Hersey — Fri, 17 Oct 2014 23:01:20 GMT

I might have been sleepy/distracted before. Modern thinking is that, in general, hi Z sources should be coupled with hi Z amps and low Z sources with low Z amps, for best noise performance, generally speaking.

Transistor Amp

nick123 — Sat, 04 Oct 2014 00:06:42 GMT

How can I make a transistor amp that can amplify a electric guitar?

RE: Transistor Amp

jw0752 — Thu, 16 Oct 2014 22:16:51 GMT

Thanks Michael, You are right as usual. I too have had problems in the past where the draw on my battery would modulate the power to the other sections of my circuit and cause problems. In addition to having a decent size cap on my power supply I have also gotten in the habit of putting a .1 cap Vcc to Vss on any IC I am working with for stability. Nick should be able to put something together from what we have given him.

John

RE: Transistor Amp

nick123 — Thu, 16 Oct 2014 21:53:06 GMT

Thanks, that looks good.

RE: Transistor Amp

nick123 — Thu, 16 Oct 2014 21:52:00 GMT

Thanks!

RE: Transistor Amp

michaelkellett — Thu, 16 Oct 2014 16:20:44 GMT

That's a good link John. I like the second (bridge) circuit best where he uses the FET follower as a high impedance buffer - certainly easier to solder than my TL071 suggestion. The only worry I would have is that the 100uF cap across the supply may not be big enough if a not very good battery/adapter is used as the power source. (Because the high currents through the speaker will modulate the 9V supply and this may upset the input buffer amp. At high frequencies the 100uF will be OK but at bass guitar frequencies (30Hz open B string) the 100uF cap has an impedance of 53R so it's not very low compared with the suggested speaker load of 4 R. 4700uF would feel better to me.

RE: Transistor Amp

D_Hersey — Thu, 16 Oct 2014 16:02:17 GMT

Opinions aside, the less noise the better:

Johnson–Nyquist noise - Wikipedia, the free encyclopedia

Shot noise - Wikipedia, the free encyclopedia

warning --math inside

RE: Transistor Amp

jw0752 — Thu, 16 Oct 2014 15:32:05 GMT

Hi Nick, I found this simple 386 Guitar Amp Project in the Instructables Site. It looks simple and it would give you a start on your project with minimal parts. Here is the link.

http://www.instructables.com/id/Portable-Guitar-or-iPod-Amplifier-Amp-9v-LM3/

Good Luck John

RE: Transistor Amp

michaelkellett — Thu, 16 Oct 2014 07:32:37 GMT

Electric guitar signals are often huge - on a recent customer project we decided that we needed +/- 3V headroom on the input of the amplifier to cope with even a reasonable range of instruments. Noise is not an issue. To avoid loading effects on the guitar/cable combination you should aim for an amplifier input impedance of greater than 1M ohm.

Norton amplifiers are not very low noise. With conventional op amps the inverting op amp configuration is much noisier than the non-inverting.

Although a bit old hat now the TL071 fet op amp is not a bad choice for the input - cheap, low noise but needs a fair bit of PSU headroom so for a guitar amp input you'll need a 10V supply (or +/-5V).

LMP7701 is a better choice for a modern part but comes in SOT23 package, OK with supplies down to 6V with guitar but will work down to 3V OK with reduced headroom.

However since the OP is talking about using an LM386 I assume he wants to keep it cheap - so I would go for a TL071 connected as a unity gain buffer with a 2.2M resistor to ground across the +ve input, driving a 10k volume control pot, then the LM386 with gain set to 20 and use a 12V supply.

Max power will be about 0.7W which is hardly in the big league of power amps.

If Nick wants more welly there are lots of other power amp ICs to consider.

RE: Transistor Amp

D_Hersey — Wed, 15 Oct 2014 22:35:01 GMT

Two things to mind when working with such a weak signal are EMI and shot noise. You should probably use a (grounded) metal box. You should consider an inverting op-amp scheme, maybe using a current-mode (Norton) amp.

RE: Transistor Amp

D_Hersey — Wed, 15 Oct 2014 22:06:19 GMT

The Zout of an electric guitar is on the order of 30K ohms. Therefore, I would work on a preamp to get me out of this regime, where I could use Plain-Off-The-Shelf tech for the right-hand side of the gain-chain.

RE: Transistor Amp

shabaz — Wed, 15 Oct 2014 22:05:59 GMT

Good idea with the LM386, it's still about the easiest-to-use audio amp around.

I know nothing about guitar pickups, but I recall the LM386 has a 'crazy gain' mode : ) where it can be turned up to huge levels (by adding or modifying one capacitor - the information is in the datasheet).

It might be enough to work with some pickups.

RE: Transistor Amp

jw0752 — Wed, 15 Oct 2014 19:04:08 GMT

Hi Nick, Yes you could use an LM386 which can give you approximately 1 watt power output. You will also have to build a preamp to drive the LM386 as the voltage from your guitar pickups is fairly low. You might be able to use an op amp like a 741 for the preamp. If you lookup data sheets on these two components they may give you some basic designs that you can build. Don't expect a lot of power but you will get a lot of satisfaction when you build it yourself and it works.

John

RE: Transistor Amp

nick123 — Wed, 15 Oct 2014 17:20:36 GMT

I don't want it to be anything expensive, just a simple amplifier that can amplify an electric guitar.

RE: Transistor Amp

nick123 — Wed, 15 Oct 2014 17:18:37 GMT

I do want to make it from scratch. also, do you think I could use an LM386?

RE: Transistor Amp

michaelkellett — Sat, 04 Oct 2014 08:32:52 GMT

Google 'diy transistor guitar amplifier', find a project you fancy and then, if you like, post about it here and we'll give your our opinions.

Otherwise give us a lot more detail re. specs and budgets and you might get some more ideas.

RE: Transistor Amp

jw0752 — Sat, 04 Oct 2014 04:52:40 GMT

Hi Nick, Do you want to make an amplifier from scratch or are you interested in making the amp from other pieces of equipment? If you are looking for something that is fairly low power you might use an amplifier that comes with auxiliary speakers for a computer. I have found that there are lots of these little amplifier systems sitting around and unused. You will have to get a small preamplifier so that you can raise the signal level of the guitar pickups enough to provide enough power to drive the input of the computer speaker amp. If you have two computer amplifiers you might be able to use one as the preamplifier and the second as the main amp. If you have more experience with electronics you could also use one channel of the computer speaker amp as the preamp and the other channel as the main amp. I have done some similar things for a couple projects. Of course it doesn't sound like a Fender Stage Amp but at least it is loud enough so you can hear what you are playing.

John

RE: demande de renseignement

Former Member — Fri, 19 Feb 2010 16:52:26 GMT

Mr Gauthier

The best way to get an answer for this kind of question is to contact the ON Semiconductor on line technical support at: http://www.onsemi.com/PowerSolutions/supportTechnical.do

They should be able to help you.

Best regards

Michel Pradille

demande de renseignement

Former Member — Wed, 17 Feb 2010 14:59:40 GMT

Bonjour,

Je suis à la recherche d'un composant CMS marqué Y1. D'aprés le site Farnell, il s'agit d'un transistor MOSFET en boitier SOT23. Le problème est que le composant monté sur ma carte en panne est en boitier SOT353.

Pouvez-vous me dire s'il s'agit bien du même composant?

Merci de votre aide.