The process of creating electronic products, including components and end-user devices.

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1answer
44 views

designing oscillator in range of 80-120 Mhz using bc547 instead of jfet? [on hold]

Can i design oscillator in this picture with using bc547, if yes, how i can do. .by the way in multism the oscillator in picture doesnt have output frequency in Mhz range.but cource lecturer did it!. ...
14
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4answers
1k views

How do you determine how much flash/RAM you need for a microcontroller?

Let's say you are starting an embedded project with some known functionality. When you select a microcontroller how do you select how much RAM you need? Do you use a developer board and code your ...
0
votes
1answer
40 views

Spread spectrum 400 KHz

I got a 6-phase DC-DC converter. Fsw=400 kHz, synchronization by external clock(CPLD). I need a spread spectrum 400 kHz. What's the best way? All chips what I've seen before worked on MHz and above. ...
0
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0answers
50 views

Design considerations for internal PC parts

I'm designing a PWM fan controller. It will be interally mounted inside a PC and will take power from the normal 4 pin Mate-N-Lock ("molex") connector. The on-board MCU and LCD will draw power from ...
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0answers
41 views

Designing Hardware [closed]

I have basic knowledge of calculating with Ohms Law but I am very unexperienced. I wanna design my own little board that I can connect to the computer, and then read out temperature, how wet the air ...
0
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1answer
37 views

Pogo Pins for 1.5mm Pitch Test Fixture

I'm working on a design and am going to source a smaller pcb and solder it to my design. Before using the sourced board I'm wanting to test it and so I'm trying to design a test fixture similar in ...
0
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0answers
52 views

How can an ASIP design be implemented in hardware at low cost?

Imagine, I have created an ASIP (Application-specific instruction-set processors) design in the IDE, have done the tests and in simulation, it works well. Now I want to test it in hardware. But it ...
0
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2answers
91 views

Looking for a huge circuit compilation [closed]

I have noticed that during my circuit design i always end up finding around the net better ways to improve my designs pic related its an example, Its a fuse blown indicator that gets improved by ...
0
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0answers
29 views

Can I power a IOIO-OTG board with the regulator on a Koala Protoboard?

I'm building a small device which uses a IOIO-OTG board. I figured I would mount my components on a Koala Protoboard along with the IOIO to use the recharging/usb regulator circuit provided on the ...
0
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0answers
78 views

Design a Mealy FSM that functions as a sequence detector, generating two outputs y, z in the following way:

Initially both inputs are set to 0. Output y is set to 1 when the sequence "10" has been applied to the input x; output y should then be reset to 0 and y should continue detecting next occurrence of ...
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0answers
73 views

How to learn circuit design if I already know some circuit theory [closed]

I'm a recently graduated electrical engineer, but my curriculum never focused on electronics, besides the standard introductory level courses. I specialized in telecommunications and I mostly work on ...
0
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1answer
46 views

Implementing F using a demultiplexer and an extra AND gate

Use a 1-to-8 Demultiplexer and an extra AND gate to create the function: F(x,y,z) = ∑m(1,3,5) If I were using an OR gate I think this would be trivial, simply put the 1 3 and 5 ...
4
votes
2answers
162 views

How does someone initially design a digital system for HDL?

So I have really been hitting the example code hard this week in an attempt to better understand some HDL design basics, specifically FPGAs with VHDL. The book I am using (if anyone is interested) is ...
0
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0answers
59 views

Tango PCB Designer

i'm trying to run the old Tango PCB on a DOSBox, on windows 8.1. I did the same things to make it run that i did on windows 7, but it's not working on windows 8.1, have anyone tried to run Tango on ...
2
votes
1answer
62 views

I'd like to improve this design to support ICSP

I'm new to electronics and this is my first circuit. I have some questions about implementing ICSP in this design. This is a bit of a long post with quite a few questions so I'll apologize in ...
1
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2answers
43 views

Karnaugh map: mirroring tables

When creating a map for n variables, we have to do (n-1) mirrorings. I wonder, why are the variables assigned in the way you see it on the picture. How do I know, when expanding a map, where to place ...
0
votes
1answer
51 views

Switching power supply using faraday cage and EMI protection?

Several switching power supplies in the market use this kind of cages to protect the circuit, however, i have this question, A) Is this used as a faraday cage due to the high frequency used by it? ...
0
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2answers
56 views

Smartphone headset jack to relay [closed]

Looking to see if anyone has seen a relay triggered by a sound file played thru the phones headset. My idea is to connect an old smartphone to my home's WiFi and then connect it to my garage door ...
2
votes
1answer
46 views

Automatic cut off after switch is pressed

I have a fun one for you. Here is my diagram: It's a 555 timer in a monostable one shot configuration. What I want to do is find a way to prevent the LED from staying on if the switch is held down. ...
1
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1answer
55 views

Modify MEMORY component to more sensibly Load/Store value?

I have created the following electrical circuit using Logisim: My ALU takes in 2 8-bit values and performs the operation set forth by the [Op Setter]. In particular, when the [Op] code is [100], ...
1
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1answer
80 views

Connect ALU to CPU in Logism Circuit Design and output to 7-segment Display?

I've been playing around in Logisim to get some experience in designing basic electrical circuits. While I'm sure not the best, I was able to put together a functional ALU: 1-Bit: This ALU is ...
0
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0answers
63 views

Possible to copy a circuit from 1 Logisim .circ file into another Logisim .circ file?

I'm using Logisim to experiment with Electrical Circuit design, and I was wondering if it is possible to copy a circuit created in 1 Logisim .circ file and place it into a different Logisim .circ file ...
0
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1answer
84 views

Amplify a 12 MHz sine wave

I need to take a 12MHz AC sine wave, from around 3.3V - 10V @ 10uA, output 50V, @ 1A (or more). I have the signal generator for signal input, but I am not certain what I need for a circuit to step ...
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2answers
45 views

Passive Filter Negative Insertion Loss

Can someone please explain to me how a passive filter could possibly have a negative insertion loss? In the attached picture, this can be seen in the C or D curves where the insertion loss dips below ...
2
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1answer
1k views

Design a 3-to-8 Decoder Using Only Three 2-to-4 Decoders

Using only three 2-to-4 decoders with enable and no other additional gates, implement a 3-to-8 decoder with enable. The inputs of the resulting 3-to-8 decoder should be labeled X[2..0] for the code ...
0
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1answer
60 views

How to explicitly connect hidden pins in eagle?

I am working on a project where I used a shift register 74HC595N which has hidden GND and VCC pins in Eagle. So I used the invoke property as shown in the pics, and connected the VCC and GND to the ...
0
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1answer
70 views

OLA adder and signed digit vhdl design problem

I have implemented the following online adder for signed digit using vhdl code and I have simulated my design according to the example table shown in the figure attached the problem is I am not ...
0
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3answers
76 views

concept for true random number generators

I have an idea. Lets say we have an unpowered TTL set-reset flip flop with both inputs tied to 5v(logic high). When we apply power to the flip flop, it goes into a quiescent state, so there is no ...
5
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1answer
266 views

Antenna Design for specific directions

I am designing an antenna for a device and was hoping to gain some insight in the correct design direction for the antenna. The Idea: A receiver & antenna that fits in a 6" diameter by 3" deep ...
0
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3answers
113 views

How to determine how much current and or voltage a given circuit “needs”?

My apologies in advance if I make any wrong assumptions. Say you have an outlet that is rated at 120V and 10A. My power adapter for my MacBook says it is rated at 16.5V and 3.65A max. How was it ...
0
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1answer
45 views

Using a digital signal to turn on and off a vibrating motor

I'm designing a circuit with the IOIO-OTG board and a vibrating motor. The idea would be to have a digital pin on the IOIO board control the state of the motor (either ON or OFF). The motor operates ...
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2answers
59 views

Building a first State Machine circuit - Technical Help

I just learned how to synthesize a diagram of a finite state machine into a diagram of a logical circuit composed of D flip flops, a clock and logical gates. However, I don't really have much ...
0
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0answers
35 views

Trouble getting push button working in Nios II

To give you an idea of what I'm trying to accomplish, the 18 LEDs on the board are to scroll right to left, then back to the right, and keep looping as such. Where the push button comes into play is ...
0
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0answers
73 views

What can I do with Cadence OrCAD software?

As the question says, what can I do with the Cadence OrCAD software rather than PCB design and schematics? I didn't understand what the Cadence website is saying. I just downloaded Cadence OrCAD 16.6 ...
2
votes
1answer
77 views

CadSoft Eagle polygon won't reach pads in Molex library

I'm using the Molex 5569 library in CadSoft Eagle. When I create a polygon, it won't reach the pads at all. The problem occurs only with components from this library. Have a look at this screenshot ...
0
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1answer
50 views

How can I trigger other circuits based on specific values of a 12 bit ripple counter?

I've built quite a few circuits but I've never really designed anything from a "schematics first" approach. Mostly just tinkered with designed and code until I got it right. Now, I want to build a ...
0
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1answer
91 views

Choosing the right capacitor

I have been told that in order to not damage a battery is better to connect it to a capacitor, to deliver current in a smooth way. This is because we are using a circuit where a peak of current is ...
2
votes
1answer
114 views

MOSFET H-bridge design

given the circuit below to be used as a H-bridge with AVR PWM. Is this a good desing to use? What can you recommend? I already built something like this but without the resistors. ( and so burned ...
0
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1answer
89 views

BJT Topologies - Design Principles at RF

Here are some rules of thumb I've learned when designing single-transistor BJT amplifiers: High input impedance is good Low output impedance is good Biasing resistors should draw ~10% of the ...
3
votes
3answers
213 views

custom FPGA PCB Design tips

I am planning to design a custom FPGA PCB. the PCB will contain sensors. I need to read the output of the sensors and process them in the processor. I have completed many projects using FPGA's, but ...
0
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1answer
97 views

Add male pin headers in DesignSpark PCB [closed]

I've been struggling with this software to find male pin header connectors but I could not find it even on the online database, has anyone an idea ? Thanks!
1
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4answers
1k views

Will my circuit work?

I have a circuit that I believe will work, but I was hoping someone could double check? Removed image to make room for edit. - Original schematic In my circuit, I use a MOSFET, a photo-interrupter, ...
1
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3answers
180 views

Are 3-8 input NAND gates common?

If I have, for example, 4-8 (or more) inputs that I need to AND together (or even NAND or OR) should I look for larger input devices like the 7430 NAND or is common practice to daisy chain multiple ...
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votes
2answers
90 views

Simplest possible oscillator (with some constraints) [closed]

I'm interested in finding an oscillator circuit that meets the following constraints: Runs on 9 volts or less Periodicity 100-1000 Hz or so Non-sinusoidal oscillation No inductors 1 transistor or ...
1
vote
1answer
39 views

Analyzing/designing positive feedback amplifier

I've been searching all around to find a tutorial on analyzing/designing a positive feedback amplifier, especially a single transistor in common collector mode, but with no luck... So, lets say I ...
2
votes
3answers
468 views

Logic design to circuit — how is it generally done?

So I've designed this CPU with purely logical components (basic logic gates), now how would I go about converting it into a circuit? I know that logical gates can be implemented using transistors, but ...
0
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2answers
157 views

Resistor required for capacitor?

I'm currently working on some simple circuits to learn about circuitry, and being a Physics major I have a pretty good grasp of the mathematics and concepts, but I'm a little confused about ...
0
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1answer
126 views

Topology for a DC-DC step up converter for a single AA battery with 50V 10mA output

I need to design a very compact step up DC-DC converter for the single AA battery (input voltage 0.7-1-5V) with an output of 50V 10mA. The load should drain in a typical case about 2mA, but in certain ...
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2answers
84 views

How many people might have been involved in the design of the Macintosh SE? [closed]

It is really difficult for me to know how many people were in charge of the development of this electronic wonder. When I'm struggling to properly comprehend transistors and how they work, these ...
1
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2answers
262 views

High EMI PCB track under transistor or diode package

Can a high EMI PCB track under a transistor or diode package (in this case TO247AC) be a problem? To get a better understanding: Is there any advantage on putting these tracks on the other side ...