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  1. Today
  2. Hi, did u got any solution for your problem coz I'm also facing same thing. Thanks
  3. Could you tell me why I need to panelize my boards when PCB manufacturing?
  4. Yesterday
  5. A tab route is used to create arrays, often called "route and retain". Tab routing lets you place more than one board (of either the same or different design) into a given area. This is typically for the convenience of the customer or for assembly requirements that utilize pick and place machines to load components. PCBs are then separated by breaking or cutting the tabs.
  6. Last week
  7. Hello everyone, What is tab route in PCB manufacturing?
  8. Earlier
  9. I'm in a joint program for computer and electronics engineering. Although I had another year to finish my first year and sign a project, I was hoping maybe I could get some ideas from some of you. I'm not looking for simple circuits, I'm not looking for anything too complex. When it is time to start the project, I will have only 3 months to investigate, build, test and finalize the project. We like https://copycrafter.net/economics-homework-help.html for him. Any help for something great to do the idea would be very helpful. I had a lot of ideas, but it wasn't financially possible after doing research. I have a spending limit of $ 300- $ 500. Thank you very much for any idea, and if I like to follow an idea, I will let you know in writing.
  10. Hello everyone, I got a suggested simple NPN circuit that worked fine with the 1.2V trigger signal. Here it is Thanks everyone.
  11. Your simulation is cheating because it uses a very high base voltage that has almost unlimited current and no voltage drop.
  12. Lets see if this is readable. Using a 2n2222 - about 10 cents apiece. Current from the source is 40ma with a base resistor of 1000 or 10k. In the view the yellow trace is the current through the relay; scale on the right . Green is the voltage at the base; scale on the left. I have no idea what the inductance would be so I set it at 0.001 henry.
  13. Hello Audioguru, and thanks for your reply. Attached is the data sheet of the relay I have. The model is SRD-06VDC-SL-C. I do not know how much current the timer can provide. I hope there is a way/component that can be triggered by the 1.2V output. Otherwise, I will have to buy a new timer, but I am really interested to get the timer I have to work, of course if possible.
  14. Same question again but on this forum. Here you forgot to say which relay you will use so we do not know its coil current then we cannot calculate how much input current a transistor needs. You also did not say how much current the 1.2V timer can produce which might not be enough current to drive the transistor. 1.2V is probably too low to activate a photo-triac.
  15. Hello everyone, I have a digital programmable timer with signal output of 1.2V DC. It runs on rechargeable battery of 1.2V. I need to use this small output to run a small 6V relay. To my general knowledge, I need at least 3 volts to trigger a small transistor. Is there a transistor that can be triggered by 1.2V signal? or can I use a photoisolator triac to drive the relay with the small 1.2V signal? Thanks.
  16. Hello everyone, as an electronic enthusiast,i'd like to share some electronic knowledge. In the circuit, capacitors is to cut off the DC through alternating current, and it is commonly used in inter-stage coupling, filtering, decoupling, bypass and signal tuning. A. Filter capacitor is used in the power supply rectifier circuit to filter out the AC component. So that the output of the DC can be more smooth. B. Decoupling capacitors are used in the amplifier circuit to eliminate self-excitation to ensure the amplifier stable operation. C. Bypass capacitor is used in a resistance connection and connected to the ends of the resistor to pass the AC signal. D. Decoupling capacitors are mainly removed from high frequency such as RF signal interference, interference is entered by electromagnetic radiation. In fact, the capacitor near the chip also plays the role of energy storage. E.The high-frequency switching noise is generated by the active device will propagate along the power line. The main function of the decoupling capacitor is to provide a local DC power supply to the active device to reduce the propagation of the switching noise on the board and to direct the noise to ground.
  17. step1 You’ll first take the schematic that you finished earlier and turn it into a new PCB layout. step2 You’ll then place and rotate all of your components, working to minimize the length and crossing of airwires (more on this later). step3 You’ll finish up your placement process by resizing the dimensions of your board layout in preparation for routing.
  18. Recently i learned some knowledge of flexible PCB. I want to share some advantages. Flex PCB(also variously referred to around the globe as flex circuits, flexible printed circuit boards, flex print, flexi-circuits) are members of electronic and interconnection family. They consist of a thin insulating polymer film having conductive circuit patterns affixed thereto and typically supplied with a thin polymer coating to protect the conductor circuits. It is now one of the most important interconnection technologies in use for the manufacture of many of today's most advanced electronic products. Generally speaking, there are 5 advantages in using Flex PCB than traditional rigid PCB. 1. Size Today's market for electronic interconnect, demands an increased number of I/Os with a high degree of performance and reliability in increasingly miniaturized packages. Constant consideration to further reduce package size is required to support tomorrow’s sophisticated product requirements. Being inherently thin, lightweight, and flexible, flex interconnect facilitates miniaturization, making it a prime candidate for portable devices and applications where space is at a minimum. Flexible PCBs have innate mechanical and electrical properties that make them an ideal selection for emerging applications. 2. Reliability Flex circuits are a reliable alternative to conventional wiring. The thin flat conductors and insulation that make up flex circuits provide more surface area than traditional wiring resulting in better heat dissipation and current carrying capacity. Flex circuits offer repeatable reliability and facilitate the replacement of heavy bulky wiring harnesses. 3. Malleable Flex circuit technology allows for three-dimensional configurations. Flex circuits have the ability to be formed around obstructions through thin openings and into confined areas. Utilizing Flex circuits for three-dimensional applications increases the reliability and integrity of the electrical connection when connecting to peripheral devices. This is achieved by removing unnecessary plated through-holes or surface-mount pads, which are created to house mechanical connectors. 4. Performance Uniform dielectric and conductor thicknesses, favorable dielectric constant and increasingly finer line and spacing geometry provide improved impedance control required for dense, high-speed signal routing. 5. Cost If the above factors don't give you reason enough to move to flex circuits, you should also consider the costs involved. Generally speaking, you really do get more for your money with flexible circuit technology. It is not uncommon to replace several electronics components with a single flexible circuit that provides equal to or better performance for your system.
  19. from: http://static6.arrow.com/aropdfconversion/ee14f7b4a3764f5a2d5bf5d73381b76d11c173d/3a3941-datasheet.pdf.pdf
  20. Connect the 48V/7A power supply directly to the 48V/6A DC motor and it works normally. But after accessing (A3941), once the logic high level control is input, an error is reported! (F1=0, F2=1). why? What are the requirements for this module for inductive loads?
  21. http://www.diy-electronic-projects.com/p272--SimpleMouse-Smartcardprogrammer For the above link, the schematics are no more available. I am trying to implement PL2303 based phoenix programmer. I made an FT232RL based design but that works as sim reader and not fully compatible with pyscard library. PL2303 based readymade card reader does...so in need of a schematic and from the above links also.
  22. Semiconductor P-N Junction Diode Working Principle Diode is the two terminal polarised electronic semiconductor device . One terminal is Anode(-) and other is Cathode(+). The cathode is marked with the silver colour or colour band. This is the simplest semiconductor device but this is very important and most useful in electronic circuits. Diode Function The main function of the semiconductor diode is the flow of electrons to totally in only one direction across it . It means Diode conducts current in only one direction. If change the polarity of diode then no any current passes through it. So we can say that diode is act as a switch which allow to conduction of current in only one direction. This is property of an Ideal Diode. An Ideal diode acts like short circuit with same polarity with supply, But in Reverse connection it acts like Open circuit means no any current flows in reverse polarity. The semiconductor Diode is formed by adding and apply a burning force or crystalization on together of P-type and n-Type materials (p-n junction). Joining of Both materials should of the same base - Ge or Si. The PN-junction is the basic root for semiconductor diodes . PN junction PN junction is made from a single piece of semiconductor of two different properties . One side is made to be P-type material and the other side is made with N-type. Both ends of the PN-junction have different properties. One end has an excess/majority of electrons and the other end has an excess/majority of holes. The p-type semiconductor is formed by adding trivalent impurities in pure or intrinsic semiconductor and n-type semiconductor is formed by adding pentavalent impurities in pure or intrinsic semiconductor. P-type materials have majority charge carriers of holes, and minority charge carriers of electrons. But in N-type materials have majority charge carriers of electrons and minority charge carriers of holes . Half part of a Si crystal is doped with trivalent impurity and half with pentavalent impurity, we get P-N junction diode. The border where p-type and n-region meets called the junction . The free electrons move from negative terminal (cathode) to the positive terminal (anode) . But the current flow direction is from positive terminal to the negative terminal. Forward bias- If p-terminal of diode is connected with positive supply and n-terminal is connected with negative supply then it is called forward bias. If the diode is forward biased, it allows the electric current flow. On the other hand, if the diode is reverse biased, it blocks the electric current flow. Reverse bias- When p- terminal of diode is connected with n-terminal of supply and n- terminal is connected with p, this connection is called Reverse bias connection. In this connection no Electrons flow and no current flows. • Depletion layer- Depletion layer created by the initial movement of majority carrier across the junction. Holes concentration on p- type and electron concentration on n-type are very high . Due to formation of p-n junction by diffusion electron moves from n-type to p-type and holes move from p-type to n-type. By the combination of electrons and holes at the junction creates ions, and there are presents only ions at the junction . Ions are non- movable. Therefore when holes passes to electrons through these ions, then +ve ions repels the holes and oppose it passing to electron, And created a resistance wall of very small width . This is called Depletion layer. Width of depletion increases in reverse bias connection. An electric field intensity is created with depletion layer. and the sign of this electric field is negative because the direction of electric fields is +ve to -ve. • Depletion layer consists +ve charge and –ve charge on either sides of junction. • Depletion layer opposes only the the majority carrier not minority carrier. • Depletion layer is also called Space charge region or transition region. • Depletion layer consists immobile charge particles. V-I Characteristics of Semiconductor P-N diode • Knee voltage- This is the minimum required voltage to start the conduction of current through diode. This is also known as cut-in voltage. This is the forward voltage at which the diode current starts increasing rapidly. The knee voltage of si diode is 0.7 voltage and 0.3v of Ge diode. • Breakdown voltage- This is the minimum amount of voltage of any insulator that makes it electrically conductor. In Reverse bias connection of pn diode. no any current flows through diode, but when we increase the reverse voltage level continuously Then diode get internally damage (breakdown) and start conduction at a fix level. Breakdown voltage is the minimum Amount of reverse bias voltage at which diode starts conduction in reverse bias connection. This breakdown characteristics of diode uses in Zener Diode which is always used in reverse bias and Limits the circuit voltage. • Doping- A material in pure form acts like insulator. So making it more conductive in nature we need to add some impurity to it. The process of adding impurities in pure (intrinsic material) is called doping to change their electrical properties.Generally trivalent and pentavalent elements are used to doping to semiconductor .When a semiconductor is doped with trivalent impurity(Boron,Aluminium) ,it becomes P-type semiconductor material. When dope any intrinsic material with Pentavalent impurity (phosphorus, arsenic,bismuth,antimony) then it becomes N-type semiconductor. • Reverse Saturation Current Both sides of p-n junction a very small amount of minority charge carrier present. P type minority charge carrier in n-type side and n-type minority charge carrier on p-type side.It also allows to flow a minority charge current. The current which is flowing by the minority carriers is called Reverse current. When a voltage applied on junction then further external reverse voltage flows due to minority charge carriers and this increases external voltage does not increases reverse current. At a voltage level where current goes on a fix maximum level and after Only voltage increases and curren does not increases . This is called reverse saturation current. Reverse saturation current remain constant with the increase of voltage, But when voltage will increase continuously then at a Level of voltage when junction will get breakdown and high reverse current will flow. Reverse saturation current depends on temperature. If temperature of junction increases , the minority charge carriers also increases. • The Width of Depletion Layer Practically The value of Depletion width vary from 0.1µm to 0.5µm Typical value of Depletion width is -0.5µm By increasing doping concentration Depletion layer width can Reduced electrons moves across the PN junction from the N-type to the P-type , they leave behind positively charged donor ions on the negative side. Holes from the acceptor impurity moves across the junction in the opposite direction into the region where there are large numbers of free electrons. As a result, the charge density of the P-type through the junction is filled with negatively charged acceptor ions , and the charge density of the N-type along with the junction becomes positive. This charge transfer of electrons and holes across the PN junction is known as diffusion . • Barrier potential/built in potential Simply Voltage form across the depletion layer is called the contact potential. The built-in potential in a semiconductor equals the potential across the depletion region in thermal equilibrium.This is also called built-in potential or barrier voltage/potential or potential hill or diffusion voltage. Contact potential always appear with in depletion layer It is noted as V0 or vbi. Contact potential of any diode can not measure by any instrument. V0 for Ge diode = 0.1v to 0.5v typically we use V0=0.2v V0 for Si diode = 0.6v to 0.9v typically V0= 0.7v Application of p-n junction diode • As Rectifier to convert AC to DC signal • Clipper circuit for clipping the signal (changing the wave shape) • To supply ( for protection from reverse supply) • Clamper circuit to restore the dc signal wave • As Voltage multiplier • In digital logic design • In Demodulation Circuits Other types of diode Photodiode, Zener Diode, Gunn Diode, Tunnel Diode. PIN Diode, Varactor Diode. Light Emitting Diode (LED), Schottky Diode, Laser Diode, Switching Diode. Also read 4017 Decade counter What is NOT Gate Inverter semiconductor diode.pdf
  23. @soldertools1 You are right, In rolling meadows this training institute is best to learn about IPC Training, Solder Rework, Solder Training, and for other PCB repair work.
  24. What is impedance (circuitspedia.com) Impedance (Z) is similar to Resistance (R) . Impedance and Resistance both oppose the current in circuit. Both are almost the same thing , But resistance related to DC Circuit. Resistance oppose the steady electric current in DC circuit. Resistance remains same (constant) at any different frequency range. Impedance is related with AC circuit. Impedance vary according to changing the frequency, this is not constant at different frequency range. Impedance also includes reactance (Inductive and capacitive property of the circuit). Reactance - Reactance is the Resistance produced to AC Currents by Inductors and Capacitors only. This is a measure of the type of opposition to AC electricity due to capacitance or inductance. The impedance is denoted by Z and unit of it is Ohm (Ω). If the level of ohm is higher then level impedance is also higher. Impedance = Resistance + Reactance (Either inductive or Capacitive or both) In DC circuit, Impedance is effective Resistance of the circuit. Z= R In AC circuits, it possesses both magnitude and phase, unlike resistance, which has only magnitude. In the case of capacitor, When the frequency increased then the resistance (Impedance ) of capacitor decreases. In Inductor this is just opposite, When we increase the frequency range then Impedance increase in inductor. Impedance Impedance is defined as combination of resistance and reactance. As we cannot assume any circuit with DC Current without Resistance , We cannot assume a circuit with AC current without Impedance. Resistive Power- Energy burns by resistive power to Heat goes through that system , In Reactive Power- the energy goes to Antennas, Speaker, transmission line, cable etc represents how much energy to be stored and propagates. Not burn to heat ie Impedance. Resistance If there is Only Resistor is connected with Load in any circuit then is called Resistor. • Reactance If any circuit there is Only inductor or capacitor connected with load. Then the value of v/I is called reactance. In Reactance There are 2 cases (1) If inductor in connected then in this case reactance is called inductive reactance, and its value in scalar form XL = ѡL, and in vector form XL=JѡL Where ѡ=2Πf. Here If frequency is increased then the value of wL is also increased. (2) If Capacitor is connected then the Reactance is called Capacitive Reactance and it is denoted by (scalar form) Xc = In vector form Where If frequency (f) is increased then value of Xc is decreased. ie ω inversly proportional to 2Πf. ♦ Impedance – If Any circuit consist Resistance -Inductor. Or Resistance - Capacitor, Or Resistance-inductor-Capacitor. Then the value of v/I is called Impedance. It is denoted by If Resistor(R) and Inductor(L) connected –The value of Impedance (scaler form) In vector form Z= R+jωL If Resistor (R) and Capacitor(C) connected - Then Impedance And In vector form impedance If Resistor (R) , Inductor (L) capacitor (C) Connected - Then Impedance In vector form Phasor Diagram of Impedance Unit Impedance - Ω Reactance - Ω Resistance - Ω Download What is impedance .pdf also read What is 555 timer What is NOT Gate Logic
  25. The 24VAC transformer probably produces 25VAC with a light load on the project. Then its rectified and filtered output is +34V and -5.6V which power the opamps. At times the voltages are higher. Your transformer will be overloaded if its power rating is 105VA or less (24V at 4.4A).. The old TL081 opamps have an absolute maximum allowed supply of a total of only 36V so they will not last long. Replace the opamps with TLE2141 opamps that have a maximum allowed supply of 44V. Many of the resistors and the driver transistor in the original project are overloaded. Upgrade them. The main filter capacitor C1 value is much too low, upgrade it.
  26. Hello. The first thing is to introduce myself and say thank you. I started with the original version and researching I have come here and I have to say that I have seen beautiful versions derived from v1. 0. I would like to keep the original project (the TL081, the toroidal transformer of 24v. . . etc), but I've already seen so many projects that I'm a mess. What I'm looking for is simplicity and I don't mind staying at 27 or 28.maximum volts. . . but toroids are not cheap here and I want to take advantage of the one I bought from 24 which one do you advise me for that 24AC transformer?
  27. Medición de variables electricas modelo #2 (Measurement of electric variables model # 2) ¿Qué es el modelo # 2? (What is model #2 ?)
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