Yes, a few of them in fact. Content is good if uneven---no glaring errors at least.
The Bode book is a classic, if not the easiest from which to learn. I came by a copy via eBay which is inscribed by Bode! Oddly the seller didn't think this made it more desirable.
The other book in that old series that is quite wonderful is Black's Modulation Theory. Gerald Stanley is a big fan of it and says Black came within a hair of inventing class I (for interleave).
The Toumazou et al. current-mode book is also good, particularly Gilbert's article.
I do recommend reading the engineering theory, understanding feedback amplifiers in general over the fanboyism and magic thinking that seems to be the mode in the CFA Topology Audio Amplifier thread
Last edited:
I will soon engage in that pastime, tourism, as my priorities are changing significantly as of late. Until that time, color me jealous.
Did the drive from Venice to Medjugorje, with stopovers in Spit and Mostar.
Don't know which was scarier. The dalmation coast, or the up front and personal with a scorpion.
Polefishing in Spit was an eye opener as well. I couldn't believe the guy tossed the entire pole into the water, now how ya gonna get it back? ...oh, nevermind..
The dalmation coast was just unbelievable once you get over the hundreds of meters drop from the road edge to the water with no guard rails..
jn
JN, agreed, the drive along the Dalmatian coast, now in the Republic of Croatia is both beautiful and deadly with even the smallest mistake. But the local population is typically as good as it gets.
AS for sightseeing - you know, it's one thing to go and see, but the thing is how you incorporate that new knowledge into your entire system of reasoning. I saw far too many dummies on whom such trips were totally wasted, and from all over the world. You certainly don't belong to that group, judging from your input here, so I feel reasonably sure such travels will indeed enlarge your scope and ultimately please you. Seeing it all with your own eyes is a hell of a lot better than watching any travel movie. There is no substitute for personal experience. I say go for it, it's always a good time to learn something new.
AS for sightseeing - you know, it's one thing to go and see, but the thing is how you incorporate that new knowledge into your entire system of reasoning. I saw far too many dummies on whom such trips were totally wasted, and from all over the world. You certainly don't belong to that group, judging from your input here, so I feel reasonably sure such travels will indeed enlarge your scope and ultimately please you. Seeing it all with your own eyes is a hell of a lot better than watching any travel movie. There is no substitute for personal experience. I say go for it, it's always a good time to learn something new.
Gilbert quote from Toumazou et al. eds.
"2.2 General Principles
This chapter will describe many examples of translinear circuits, which come as close to true current-mode operation as any circuit can.
At the outset however, it must be stated that the term "current-mode circuit" has no rigorous meaning. The behavior of electrical networks is always the result of an interplay between voltage and current..."
(from Analogue IC Design: the current-mode approach, Toumazou, Lidgey, and Haigh eds., ISBN 0863412971)
"2.2 General Principles
This chapter will describe many examples of translinear circuits, which come as close to true current-mode operation as any circuit can.
At the outset however, it must be stated that the term "current-mode circuit" has no rigorous meaning. The behavior of electrical networks is always the result of an interplay between voltage and current..."
(from Analogue IC Design: the current-mode approach, Toumazou, Lidgey, and Haigh eds., ISBN 0863412971)
I can't believe there is not one single person here who can recommend a single pakage dual NPN JFET from a reputable source of non-Chinese origin? Or can say where it can be bought?
One reason that we are so easily thinking in voltage terms rather than current terms is that it is so easy to measure voltage, just hang a pair of probes in the circuit. Measuring current is MUCH more difficult. Try to find a current probe that measures down to 1mA with low noise - while digital voltmeters routinely measure 1mV with low noise.
But of course, it's all connected through Mr. Ohm.
Jan
Of course you mean a dual N-channel JFET.
There is a distributor for Linear Integrated Systems with offices here and there. LIS have their sub for the Toshiba 2SK389, the LSK389. They have a smaller geometry part, the LSK489. Both are available in leaded and SM I believe. And they make a few others: Linear Systems || Products
Toshiba has discontinued all, or nearly all, of their leaded parts, I think. However there is a SOT-23-5 part that is about the same as two 2SK117, the 2SK2145. I don't know who the distributors may be. I don't appreciate that they tied the sources together---a decision by someone who assumes we would only wish to use the pair as a differential pair with no source degeneration. Short-sighted.
Interfet makes some legacy duals, and some exotic large-area parts on special order. LIS and Interfet are US-based. They now mention Mouser is a distributor. InterFET Corp. InterFET
Brad
> I don't know who the distributors may be.
2SK2145-BL(TE85L,F Toshiba | Mouser
2SK2145-Y(TE85L,F) Toshiba | Mouser
2SK2145-GR(TE85L,F Toshiba | Mouser
Source / drain are interchangeable.
So no problems making diff pair or source follower from 5 pins.
Patrick
2SK2145-BL(TE85L,F Toshiba | Mouser
2SK2145-Y(TE85L,F) Toshiba | Mouser
2SK2145-GR(TE85L,F Toshiba | Mouser
Source / drain are interchangeable.
So no problems making diff pair or source follower from 5 pins.
Patrick
Thanks Patrick, nice to see that Mouser also distributes Toshiba here.
Yes, agree that you can get a source follower out of it readily enough. But it is still inflexible for some configurations I like, including a grounded source amplifier loaded with a matched current-source load, or composite halves of a diff amp that requires independent channels. Or as parts for one of your current conveyors with individual cascoding.
One more pin... At least the parts seem to be dielectrically isolated, so the problem of voltage-dependent substrate capacitance is eliminated.
Brad
Bcarso, EUVL,
Thank you, that's exactly what I wanted.
On joining the sources - I totally agree, that's an old problem with far too many otherwise excellent parts from Japan, JFET or bipolar. Very short sighted, as you say Brad, if anyone likes just that he can always join them on the PCB, but we who don't like that cannot undo what they built into the hardware.
Thank you, that's exactly what I wanted.
On joining the sources - I totally agree, that's an old problem with far too many otherwise excellent parts from Japan, JFET or bipolar. Very short sighted, as you say Brad, if anyone likes just that he can always join them on the PCB, but we who don't like that cannot undo what they built into the hardware.
I made a search and I don’t find this book.
Can you provide more details?
But I found the “Avoiding Singing”
https://archive.org/details/bstj13-1-1
George
Bookfinder.com yields up a number of copies for sale. I would paste one of the links in, but they expire rapidly. Harold S. Black, Modulation Theory, Van Nostrand, 1953. Pre-ISBN days, although there was a reprint edition apparently. Here's one seller's description of the first edition:
Hardcover
Publisher: D.Van Nostrand, Princeton, N.J., 1953
Used - Very Good. Classic comprehensive text presents detailed topics dealing with the history and fundamentals of modulation theory, including coverage of types of modulation; sampling principle; quantization, code transmission, and multiplexing; speed of signaling and channel capacity; reduction of signal power through the use of redundant codes; amplitude modulators and demodulators; amplitude-modulation systems; frequency modulation; noise and interference in FM systems; pulse-amplitude... (COMMUNICATIONS, ELECTROMAGNETICS, CODING, BELL SYSTEM, SIGNALS, AMPLITUDE, PULSE-CODE, ENGINEERING, SEMICONDUCTORS, NETWORKS, MATHEMATICS, ELECTRONICS, ENTROPY, MULTIPLEXING, TRNSMISSION, AERONAUTICS, DECODERS, WIRELESS, RADIO, SCIENCE, TECHNOLOGY)
Here is an approach to dealing with the connected channels on the SK2145 and other similar duals. It uses one half of the dual as a current sink which is filtered and mirrored, a Wilson mirror with ballasting for lower noise shown here. Of course one can cascode each JFET for higher gain at the output and reduced Miller capacitance at the circuit input, and the output must be level-shifted, most likely, for succeeding stages. The Wilson mirror can benefit from a final additional bootstrapped cascode as well. Thus one gets a high-gain inverting amplifier with the noise almost as low as a single JFET, with input offset voltage close to zero.
It does require spending some volts, and the stage output is very high impedance.
Attachments
These are well distributed and cheap, at least worth a look. Same AM radio reference app. so gm is good and noise probably pretty good. All 6 leads brought out, but micro SOT only.
http://www.nxp.com/documents/data_sheet/PMBFJ620.pdf
The equivalent noise resistance is ~.7/gm where the gm is the net transconductance of the two in parallel. So two in parallel and 2X the net current is the same -3dB as doubling the collector current (within limits) of a bipolar. The noise of JFET's goes as the fourth root of Id (again within limits) so you have to double the current and the size.
- Status
- Not open for further replies.