Today I received an e-mail from a list that I'm signed talking about a real-time logic simulator.
Its' named Atanua (according to documentation I read, the name comes from Polynesian mythology, where Atanua is the goddess of dawn.)
In this link you can see a demo.
There is a free version for personal, noncommercial use that you can get here.
The coolest thing is that there is a Linux version (compiled on Ubuntu 8.04), for Mac and Windows.
I already downloaded my version (for Linux, of course) and I'm going to play with it to see if it is as good as it seems on demo.
Do not waste time. Download and install the simulator and start playing / learning.
Mostrando postagens com marcador electronics. Mostrar todas as postagens
Mostrando postagens com marcador electronics. Mostrar todas as postagens
segunda-feira, dezembro 28, 2009
sexta-feira, novembro 27, 2009
terça-feira, novembro 03, 2009
SPICE Models
All flavors of SPICE simulators comes with a reasonable number of models that are more than enough for beginners.
And as your skills increase, so will your need for more specific models.
The following list of links has many SPICE models available for free. I hope it will be useful to you.
From time to time I will update it.
And as your skills increase, so will your need for more specific models.
The following list of links has many SPICE models available for free. I hope it will be useful to you.
From time to time I will update it.
- Philips
- STMicroelectronics
domingo, outubro 18, 2009
Spicing up your design
I'm an old school hobbyist. I have fun building my projects and I never was a big fan of circuit simulations. The latter is not as funnier as the former.
Unfortunately, as I've already written here, Electronics is more expensive than software development. In order to have a good lab you need at least a good oscilloscope, two 0-30 VDC stabilized power supply with current control from 0 to 3A, a signal generator, a multimeter and a bunch of tools and components.
The problem is that it costs money. More than I'm willing to expend now. So, in order to save some money and at the same time keep studying and developing my circuits, I decided to use SPICE.
SPICE, my dear friend, is a circuit simulation tool that is very useful in the design cycle. The use of SPICE will let me correct my design flaws even before I need to expend a single resistor. So I will be able to test many different configurations and choose the best one while keeping costs low.
There are many flavors of SPICE available. I chosed LTSpice from Linear Technologies by many reasons: it is reliable, there are many LTSpice users that can help me solve my problems, it includes a wide variety of pre-built designs that makes it easy to learn LTSpice, there are many tutorials about it on the net, it is fast and it is free. More over, it is a Windows application that runs very well on Linux (thanks to WINE). And it is essential to me
I will write down everything I've learned during my self study on SPICE simulation.
Unfortunately, as I've already written here, Electronics is more expensive than software development. In order to have a good lab you need at least a good oscilloscope, two 0-30 VDC stabilized power supply with current control from 0 to 3A, a signal generator, a multimeter and a bunch of tools and components.
The problem is that it costs money. More than I'm willing to expend now. So, in order to save some money and at the same time keep studying and developing my circuits, I decided to use SPICE.
SPICE, my dear friend, is a circuit simulation tool that is very useful in the design cycle. The use of SPICE will let me correct my design flaws even before I need to expend a single resistor. So I will be able to test many different configurations and choose the best one while keeping costs low.
There are many flavors of SPICE available. I chosed LTSpice from Linear Technologies by many reasons: it is reliable, there are many LTSpice users that can help me solve my problems, it includes a wide variety of pre-built designs that makes it easy to learn LTSpice, there are many tutorials about it on the net, it is fast and it is free. More over, it is a Windows application that runs very well on Linux (thanks to WINE). And it is essential to me
I will write down everything I've learned during my self study on SPICE simulation.
quinta-feira, outubro 15, 2009
Electronics and software development are too similar
Electronics and programming, both are my hobbies. I see many similarities between them. Especially in the way we do things.
A project using just discrete components (resistors, capacitors, transistors, etc.) means that your circuit will be too big, you will have a lot of work to project it in the right way and it will cost a lot of money too. Sometimes it's not viable to design using only discrete components.
The circuit is very susceptible to mistakes and it is hard to fix it.
This is the equivalent of assembly programming. It is not practical to develop a large program entirely in assembly. Can you imagine a CRM software such as SAP, entirely written in assembly? What about Oracle? And Linux?
Projects that use discrete and low-scale integration IC components (e.g. operational amplifiers and 74xx or 4XXX family of logic gates) are easier to make, since we have a library with basic functions (the 741 operational amplifier, for example contains 20 transistors and 11 resistors and occupies only 0.400 x 0.290 inches).
In my opinion, this kind of assembly is similar to program in C. We have a tiny wrapper around assembly language. This turns our development efforts into an easier task and at the same time it doesn't put us far way of its guts.
When we build using specialized ICs, like audio amplifiers, horizontal and vertical synchronism ICs, among others, the PCB size reduces as well as complexity and development time. I make an analogy with software development using java.
The more specialized the ICs we use the more similar to frameworks and high-level languages (Ruby on Rails, for instance) we get.
This analogy is not perfect but makes me thing: I enjoy more programming in C and in Assembly languages than to program in high level languages. At the same way, I enjoy more assembling electronic circuits using discrete components and basic ICs (like operational amplifiers and logic gates) than using very specialized ICs.
I'm not an extremist. I use high-level languages on software development and specialized ICs (micro controllers, for instance) on electronics circuits when it is needed.
From a pure performance standpoint, such as execution speed, code written in assembly language means efficiency, in Electronics it is not true.
The initial investment needed to professionally work is lower on software development than in Electronics.
Another point where software development and Electronics differ is in the reuse of created stuff. A library must be done just once on software. Then you can reuse it as much as you need it for free! In Electronics, on the other hand, each circuit built comes at least with the cost factor for acquiring components (and many times this cost factor is no so small).
I summarized everything into a table.
Have you ever though about it? Is it just me?
I'll stop divagating for a while. When I find out new similarities I will write again.
A project using just discrete components (resistors, capacitors, transistors, etc.) means that your circuit will be too big, you will have a lot of work to project it in the right way and it will cost a lot of money too. Sometimes it's not viable to design using only discrete components.
The circuit is very susceptible to mistakes and it is hard to fix it.
This is the equivalent of assembly programming. It is not practical to develop a large program entirely in assembly. Can you imagine a CRM software such as SAP, entirely written in assembly? What about Oracle? And Linux?
Projects that use discrete and low-scale integration IC components (e.g. operational amplifiers and 74xx or 4XXX family of logic gates) are easier to make, since we have a library with basic functions (the 741 operational amplifier, for example contains 20 transistors and 11 resistors and occupies only 0.400 x 0.290 inches).
In my opinion, this kind of assembly is similar to program in C. We have a tiny wrapper around assembly language. This turns our development efforts into an easier task and at the same time it doesn't put us far way of its guts.
When we build using specialized ICs, like audio amplifiers, horizontal and vertical synchronism ICs, among others, the PCB size reduces as well as complexity and development time. I make an analogy with software development using java.
The more specialized the ICs we use the more similar to frameworks and high-level languages (Ruby on Rails, for instance) we get.
This analogy is not perfect but makes me thing: I enjoy more programming in C and in Assembly languages than to program in high level languages. At the same way, I enjoy more assembling electronic circuits using discrete components and basic ICs (like operational amplifiers and logic gates) than using very specialized ICs.
I'm not an extremist. I use high-level languages on software development and specialized ICs (micro controllers, for instance) on electronics circuits when it is needed.
From a pure performance standpoint, such as execution speed, code written in assembly language means efficiency, in Electronics it is not true.
The initial investment needed to professionally work is lower on software development than in Electronics.
Another point where software development and Electronics differ is in the reuse of created stuff. A library must be done just once on software. Then you can reuse it as much as you need it for free! In Electronics, on the other hand, each circuit built comes at least with the cost factor for acquiring components (and many times this cost factor is no so small).
I summarized everything into a table.
| Electronics | Software | |
| low level | discrete components | assembly language |
| mid-level | discrete and low-scale integration IC components | C language |
| high-level | specialized ICs, like audio amplifiers, horizontal and vertical synchronism. | Java / C# |
| very high-level | very specialized ICs | Ruby on Rails |
| initial investment needed to work | high | no so high |
| lowering costs by reusing libraries | no so high | high |
Have you ever though about it? Is it just me?
I'll stop divagating for a while. When I find out new similarities I will write again.
sexta-feira, setembro 25, 2009
Human Synthesizer
Who said Science cannot be funny?
Here you can the see a human synthesizer in action and how it was done (with an Arduino).
Here you can the see a human synthesizer in action and how it was done (with an Arduino).
sábado, agosto 22, 2009
Free ARM microcontroller
Three weeks ago I read on blog do Jê, that NXP was offering free samples of its microcontrollers LPC1766, LPC2478, LPC3130 and LPC3250.
I ordered the samples at NXP's home page. It arrived on August 18, 2009.
I didn't receive samples of all microcontrollers as I've ordered, I received just one sample of LPC1766. Anyway, I am very satisfied and I plan to use it as soon as possible.
If you like Electronics like me and you're interested on microcontrollers, give you a chance to get some free samples too. Up to the moment I was writting this post you could order them here.
I ordered the samples at NXP's home page. It arrived on August 18, 2009.
I didn't receive samples of all microcontrollers as I've ordered, I received just one sample of LPC1766. Anyway, I am very satisfied and I plan to use it as soon as possible.
If you like Electronics like me and you're interested on microcontrollers, give you a chance to get some free samples too. Up to the moment I was writting this post you could order them here.
terça-feira, janeiro 20, 2009
Free magazine about PIC and electronics
Do you like electronics? And what about PIC microcontrollers?
Today I am writing to share the URL of an amazing site named MicroPIC. This site has many projects and tutorials. There is even a e-magazine named uControl they release for free.
If you can read Spanish go to MicroPIC and enjoy this site. I am pretty sure you will find many interesting things there.
Correction: I made a mistake when I wrote this post. uControl is not edited by MicroPIC but by a site named uControl (it is written in Spanish too).
You will see references to the e-magazine on MicroPIC but they never claimed to be the authors.
That said I restate that MicroPIC is an amazing site. Moreover, uControl is amazing too.
Today I am writing to share the URL of an amazing site named MicroPIC. This site has many projects and tutorials. There is even a e-magazine named uControl they release for free.
If you can read Spanish go to MicroPIC and enjoy this site. I am pretty sure you will find many interesting things there.
Correction: I made a mistake when I wrote this post. uControl is not edited by MicroPIC but by a site named uControl (it is written in Spanish too).
You will see references to the e-magazine on MicroPIC but they never claimed to be the authors.
That said I restate that MicroPIC is an amazing site. Moreover, uControl is amazing too.
domingo, março 16, 2008
Precision Resistors
A lot of hobbyists want to make their own circuits but they face a problem: precision resistors.
There are many projects where the ratio between resistances is more important than the actual values. In these case we can measure our resistors to select the most appropriated.
Let me show an example. Suppose we have an inverter amplifier as shown in figure 1.
Figure 1 - Inverter Amplifier
Gain is determined by equation
We can see that the circuit's gain is determined by the ratio between Rf and Ri.
Suppose we want a gain of X.
If Rf = 10,000 ohms and Ri = 5,000 ohms the gain is -2.
If Rf = 20,000 ohms and Ri = 10,000 ohms the gain is -2 too.
If we use resistors with tolerance (precision) of 5% the gain could vary between -1.81and -2.21 depending on real values of resistors Rf and Ri.
If we use resistors with tolerance (precision) of 2% the gain could vary between -1.92 e -2.08 what is much better.
What if we don't have precision resistors? What can we do?
We can use our ordinary resistors (tolerance of 5%). Take a bunch of them and measure each one until you find two resistors with a resistance ratio as near as possible of the value we wish (It is 2 in our sample).
Let me illustrate with an example. Say we take a bunch of resistors of 20K and 10K ohms (nominal values) to measure.
Suppose we found some resistors of 20,900 and 10,400 ohms. So we could do Rf = 20,900 ohms and Ri = 10,400. With these values, the gain would be -2.01 that is a better result than estimated with 2% tolerance resistors.
If we found Rf = 21,000 and Ri = 10,500 than the gain would be exactly 2.
The method, presented in this post, to use ordinary resistors instead of precision resistors is suitable only in prototype development. In commercial scale it is not feasible and the use of precision resistors is mandatory.
Note: As Maurício de Oliveira wrote in his answer to the brazilian portuguese version of this article, precision resistors are manufactured in a way that they take in account changes in their resistance by changes in temperature and manufacturers to their best to minimize it.
So, there are differences between precision resistors and ordinary resistors.
In this article (that I wrote to hobbyists), I am not taken this in account because hobbyists don't design professional circuits and then it will not cause too much trouble. Then it is a valid approuch for a experimental circuit.
There are many projects where the ratio between resistances is more important than the actual values. In these case we can measure our resistors to select the most appropriated.
Let me show an example. Suppose we have an inverter amplifier as shown in figure 1.
Figure 1 - Inverter AmplifierGain is determined by equation
We can see that the circuit's gain is determined by the ratio between Rf and Ri.Suppose we want a gain of X.
If Rf = 10,000 ohms and Ri = 5,000 ohms the gain is -2.
If Rf = 20,000 ohms and Ri = 10,000 ohms the gain is -2 too.
If we use resistors with tolerance (precision) of 5% the gain could vary between -1.81and -2.21 depending on real values of resistors Rf and Ri.
If we use resistors with tolerance (precision) of 2% the gain could vary between -1.92 e -2.08 what is much better.
What if we don't have precision resistors? What can we do?
We can use our ordinary resistors (tolerance of 5%). Take a bunch of them and measure each one until you find two resistors with a resistance ratio as near as possible of the value we wish (It is 2 in our sample).
Let me illustrate with an example. Say we take a bunch of resistors of 20K and 10K ohms (nominal values) to measure.
Suppose we found some resistors of 20,900 and 10,400 ohms. So we could do Rf = 20,900 ohms and Ri = 10,400. With these values, the gain would be -2.01 that is a better result than estimated with 2% tolerance resistors.
If we found Rf = 21,000 and Ri = 10,500 than the gain would be exactly 2.
The method, presented in this post, to use ordinary resistors instead of precision resistors is suitable only in prototype development. In commercial scale it is not feasible and the use of precision resistors is mandatory.
Note: As Maurício de Oliveira wrote in his answer to the brazilian portuguese version of this article, precision resistors are manufactured in a way that they take in account changes in their resistance by changes in temperature and manufacturers to their best to minimize it.
So, there are differences between precision resistors and ordinary resistors.
In this article (that I wrote to hobbyists), I am not taken this in account because hobbyists don't design professional circuits and then it will not cause too much trouble. Then it is a valid approuch for a experimental circuit.
Assinar:
Postagens (Atom)