Frequently Asked Questions
Mon-Fri, 9am to 12pm and
1pm to 5pm U.S. Mountain Time:
Chat With Us
June 10, 2011
News - According to Pete - July …
about 4 years ago
Pete, thanks for that. I am familiar with the concepts of approximations in Diodes and many other devices such as the First Approximation (AKA Ideal Approximation) where we ignore the barrier potential of the device, the Second Approximation which includes the barrier potential, and the Third Approximation concept which includes both the barrier potential and the bulk resistance defined as the resistance of the N-Region material PLUS the resistance of the P-Region material as an idealistic concept at best which is derived from the instructional concept that the P and N materials are first created and then magically combined at an abrupt junction when in actuality they are actually created within the same crystalline substance during the manufacturing process and thus, as a result, forms a gradual change from one type material to the other. Sorry if I am a bit more technical than most, just my nature and a result of my preferred learning style. I was just simply wondering where the 0.6V concept came from rather than the usual concepts covered in textbooks that state to use 0.3V for Germanium and 0.7V for Silicon that generally are used. I do have some ideas for making a video or series of videos but I am still developing some ideas to include along those ideas. Are you offering me a job or are there any available jobs there for me at Sparkfun? :)
Sorry, my last sentence of my last post may not have made sense. It was supposed to say: I was wondering if you had any other reasons for why using a Zener diode as a stand alone voltage regulating device in a DC power supply is a bad design choice, if so, please share.
Pete, FYI (as a review of what you already seem to know) and for anyone else who wants to know:
N-Type material is created by doping the molten silicon with Pentavalent atoms (Atoms with 5 valence shell electrons). Pentavalent atoms include: Arsenic, Antimony, and Phosphorous.
P-Type material is created by doping the molten silicon with Trivalent atoms (Atoms with 3 valence shell electrons). Trivalent atoms include: Aluminum, Boron, and Gallium.
I wanted to share this as you stated in the video that you had forgotten the elements for doping the material to create the N-Type and P-Type materials.
By the way I noticed that you stated that the forward voltage drop across the diode (AKA Barrier Potential) and the base-emitter Diode or PN junction in your discussion is about 0.6V but I always learned it as approximately 0.3V for Germanium and approximately 0.7V for Silicon. Are you using another approximation or a roundabout figure for what actually appears across most components? I do know that when measured the measured voltage drops do range in value between 0.6V and 0.7V.
Also, I noticed that you stated that it was not a good design to use a Zener diode as a device for regulating a power supply. I do know that the Zener does cause the circuit to use more power than perhaps the Series Pass Transistor regulator that appears in most Semiconductor textbooks (but is never given much discussion on its design) or even most dedicated IC voltage regulators that are readily available. I believe also that while Zener diodes provide good regulation, with only minor fluctuations (which are within a few tenths of a volt) during their operation in circuit and that the Zener, when used as a voltage regulator in a power supply, may also generate excessive noise in the circuit. However, they are very good for instructional purposes with beginners who are learning about simple ways of how to create simple regulated DC power supplies, and I am sure that you would agree with that. I was just wondering if you had any other reasons for why using the Zener diode as a stand alone voltage regulation device in power supplies, if so, please share.
about 4 years ago
Wow, the Arduino inventor’s kits really do sell out fast. I am sure glad that I placed my order when I did. I placed my order about 1am on June 10, 2011 when it said that there were 46 of the inventor’s kits with retail cases left in stock. It is now 5pm here on June 10, 2011. Oh cool!!! I just now received the email notification that my order has shipped, right on!!!!!!
No public wish lists :(
Forgot your password?
No account? Register one!