Digital electronics use a finite number of states, unlike analog electronics that treat continuous signals. Digital logic is used to perform arithmetic operations with electric signals, and constitutes the base for building CPUs.
2
votes
0answers
78 views
Digital automatic gain control? [duplicate]
Possible Duplicate:
Calculating dBFs from RSSI
My RF chip doesn't have any RSSI output, just ADC I and Q. I was wondering is it possible to determine RSSI from ADC's I and Q values and ...
1
vote
1answer
225 views
Combinational Logic Design, Truth table and K-Map question
This question is for logic computer designs, I hope it's okay to post it here. It's actually a very simple question I guess.
In this screenshot below, how did they implement the K-Map from the Truth ...
1
vote
1answer
229 views
How can I use NAND gates to divide (5bit) binary inputs by an integer (say 5)?
Trying to sketch up a circuit which will divide, say a 5-bit binary number by 5 to produce a 4-bit binary quotient.
We can assume that the input doesn't actually reach 31, instead it's limited to 30, ...
1
vote
2answers
267 views
Switch hookup with relay (arduino)
Hey all i have the following 5v relay board:
Please ignore the light bulb hook up. That was an example on the website that had the same relay :)
And i am looking to hook one of the relays up to a ...
0
votes
2answers
138 views
In Digital Multimeter note accuracy in digits
I have digital Multimeter noted in the multimeter accurcy is range 0 - 1000v at 0.2% +30 digits in this range what is 30 digits?
10
votes
1answer
900 views
Getting a large number of (~100) digital output signals from Arduino
I would like to be able to control around 100 independent LEDs using an Arduino. The problem is that the Arduino does not have nearly enough pins that can be configured for this. What would be a way ...
1
vote
1answer
328 views
16-to-4 Encoder Using 8-input NAND
Is it possible to make a 16-to-4 encoder using just 4 8-input NAND gates?
Encoders are generally implemented using or gates from my understanding. Can anyone provide any insight into developing an ...
0
votes
1answer
87 views
Are there many logic circuit solvers available to test / download? [closed]
All -
I have found something called "Simple Solver" located here:
http://home.roadrunner.com/~ssolver/syn.html
and you can download it here
...
0
votes
1answer
195 views
Problem Controlling Digital Potentiometer with Micro
I am trying to control a digital potentiometer with a PIC18F14K50 and am having a random problem (potentiometer not remembering correct value) when I power off then back on. The X9313 datasheet states ...
1
vote
2answers
127 views
Is there any such logic gate that accepts inputs from both sides and also stores information within the gate itself?
I'm trying to design a logic circuit that will end up looking a binary tree (there will be a "root" logic gate at the top and a whole bunch of "leaf" logic gates at the bottom).
Input is fed as ...
0
votes
1answer
126 views
How would I design a simple logic circuit for 3 input bits?
All -
Suppose I have 3 input bits
Bit #0
Bit #1
Bit #2
I need to design a logic circuit has follows:
Input: Bit #0 = 1, Bit #1 = 1, Bit #2 = 0
Output: 0
Input: Bit #0 = 1, Bit #1 = 0, Bit ...
2
votes
2answers
161 views
Delay in Combinational Logic Circuits/Stability
What does it mean for an output signal to be stable? Is my understanding correct that when an input to a logic circuit changes, the time delay for the signal to reach the output (the time for the ...
0
votes
0answers
165 views
How do you design a logic circuit for something that pairs all 1's with 1's and 0's with 0's? [closed]
All
Image # 0 (This is a balancer)
Image #1 (this is a balancer that I drew with concrete input bits)
The image#2 below zooms out and shows an odd-even splitter that includes the (16,8) ...
2
votes
1answer
158 views
About Quine-McCluskey method on circuit design and don't cares
My teacher have give me a question is like this.
Design a 2-of-5 Code to BCD 8421 Code converter. Minimize each of the output to SOP form using Q-M method and draw the circuit diagram using basic ...
0
votes
1answer
121 views
Minimization of Logical Equations
I have been giving a problem were I have to design 1-bit subtractor, which performs single bit binary subtraction. It has three inputs: the digits ai, bi (bi is subtracted from ai) and the borrow from ...
2
votes
4answers
2k views
Logic gate counter on 7 segment display
Using logic gates with general purpose transistors, I want to display numbers on a 7-segment display depending on the 2 pushbutton input. If both buttons are not pressed, I want it to say 0. If 1 is ...
0
votes
0answers
41 views
Loking for help in a pov led design capable of video [closed]
Im looking for someone who has the expertise to design a pov capable of video using full color and similar to the big wheel pov for bicycle's, the one I want designed and built will have approx, 72 ...
3
votes
2answers
134 views
Magnetic core transfer loops (logic)
I have an interest in "alternative" logic gates, as in not silicon transistors. I have built RAM in a little game called "Powder Game", constructed "one-off" logic gates out of exploding lattices of ...
1
vote
4answers
264 views
How to find a DIP component implementing this simple logic?
I need to implement this logic in a very simple circuit. It will be perfect if I can use a single component in a DIP package, implementing the logic. How can I find one?
0
votes
0answers
53 views
Digital I/O PCI Express card compatible with Mac [closed]
Are there any digital I/O PCI Express cards on the market that are compatible with Mac Pros?
I am looking for something like this or this that has drivers for Mac, and can be accessed using C/C++.
3
votes
1answer
196 views
4-Input NAND Gate Reduction
I'm designing a circuit using Logisim that I will later physically implement. Unfortunately, the gates provided to me in the physical implementation do not include one of the gates I used in my ...
1
vote
2answers
136 views
Is there a way to wire a digital display into a thermistor input to read the value of that thermistor?
I have a solar thermal system on my house and that system is run by a differential temperature controller having two thermistors. The controller does not have any kind of readout on it, thus I have no ...
3
votes
1answer
256 views
Verify Truth Table: Switches and LED
I got a digital design problem. My final implementation of the circuit program didn't achieve the required criteria, so I brought my problem and my works here to be suggested by you if I ...
0
votes
0answers
37 views
Useful programming languages for hardware programming [duplicate]
Possible Duplicate:
Programming languages for electronics engineers
i am thinking to take the next semester a course called "Digital systems architecture", and i know that we need to ...
4
votes
4answers
261 views
Using an open-collector output from one IC to trigger a level change on the input pin of another IC?
So my problem is simple: I have an IC that provides an output pin to alert you when some condition is met. The output pin is open-collector, high-impedance when active. I want to monitor this output ...
5
votes
2answers
710 views
Multiplexing 2 digit 7Segment with one Bit
I want to control a 2 digit 7-segment LED with a MSP430 micro controller. The display has 8 input pins per digit (8th pin is the dot, which I do not need) and two ground pins (common cathode). The ...
3
votes
1answer
1k views
Determining the truth table and simplifying logic expressions (full adder)
I've been taking an intro computer architecture class and doing some research of my own, I've found the following exercise:
Determine the truth table and simplify the logic expression derived from the ...
3
votes
1answer
194 views
How to embed a clock oscillator inside a digital block? Specifically, how is this defined for Synopsys DC?
I have to embed a clock oscillator inside my logic block for layout purposes. It's not an option to leave this block out and just bring the clock port in. Is there any way to define an internal net as ...
0
votes
1answer
139 views
Regular or Irregular Hardware?
I have a hardware structure (described in logic diagram consisting of adders and multipliers) that is extremely regular, i.e., one small hardware is repeated again and again in the structure with ...
7
votes
3answers
498 views
Using SPST switch as digital input?
I am new to "electrical engineering" and I am working on a little arduino project. I want to have a SPST switch be used as a digital input on the board.
I have one of the switch leads connected to ...
6
votes
4answers
433 views
Logic gate symbol vs IC symbol
When I'm using a logic gate (let's say AND) in a schematic, which symbol should I use: the AND symbol or the IC symbol (the 4081, for example)? Or in the case of flip-flops, should I use the flip-flop ...
0
votes
1answer
265 views
graphical circuit simulator like logisim
I wanted to make a CPU and then somehow measure its efficiency/ speed. Logisim is a little buggy, and I don't think it allows you to do any sort of testing/ measurement. Does a tool like this exist?
2
votes
1answer
51 views
Connecting two CMOS transceivers on different boards
I have a main board (with DSP controller & CMOS Transciver) and an daughter board (with CMOS Transciver, Ethernet & GPIB controller). these two boards are connected with DIN connector with ...
1
vote
2answers
296 views
how do I put this schematic into a breadboard?
I need for a project to make an electrical dice in a PCB, but first I need to prove the design in a breadboard, I really don't understand all the schematic, so I need a huge help on this. ...
2
votes
1answer
237 views
High/Low level voltage specs for an IC
I'm trying to work out whether I can talk via SPI without level conversion between a PIC at 5V and an MCP3202 ADC at 4.096V (Vref and Vdd share a pin on the ADC).
I looked at the data sheet for ...
-1
votes
1answer
153 views
What would be a Good Digital design learning project [closed]
What would be a good digital design project using vhdl that would require significant effort (maybe takes about 4hours/day and would take from a month to two month) as far as research and learning new ...
4
votes
3answers
681 views
Detecting phase between square wave and sine wave signals
I have a circuit that has a digital square wave input (generated by PLD, 1.8Vp) and a sine wave output (0.5 - 3.5 Vp). Both signals have 100kHz frequency, however the phase is different.
What is a ...
1
vote
1answer
209 views
Looking for an easy to use circuit design software similar for beginner
I'm teaching my son digital circuit design. I am looking for an easy to use design tool that can serve to sketch out the circuit and simulate it before we go and blow chips and money. The ideal ...
1
vote
3answers
195 views
How to go from GPIO to digital signal?
I'm sitting here with my Raspberry PI and some other equipment that requires digital signal (high/low, enabled/disabled).
But the Pi only has a GPIO so to get it to work I would need a microchip of ...
5
votes
4answers
317 views
Common Analog Signal Frequencies
I'm trying to scope out what frequencies different common analog signals are. The DPScope design specs provides a list of common lower (sub 1 MHz) frequencies (copied below).
audio (20 kHz)
...
2
votes
1answer
245 views
Should I use pull up resistors in this configuration?
I am interfacing a 3.3V FPGA to a 5V DSP. I am using this bidirectional voltage transceiver:
http://www.nxp.com/documents/data_sheet/GTL2000.pdf
In the diagram in page 4 they're using pull up ...
5
votes
1answer
133 views
Need 1-4 pins controlling 16pins logic level
I have max four outputs coming from a PIC. I need these four outputs (or one serially) to simultaneously control 16 pins with a logic level. This is for a clock application.
A BCD could accomplish ...
5
votes
1answer
196 views
One-clock increment operation in a three-bus CPU architecture
In his chapter on CPU design, Edward Bosworth introduces the following three-bus architecture:
One of the main design aims of this circuit is to be able to increment the program counter PC in a ...
2
votes
2answers
397 views
Maximum input frequency of 74HC Logic gates
I have a clock that is running at 25.175MHz I want to run that signal through some basic logic gates from the 74HC series.
I have looked on the datasheet for the 74HC08 (AND Gate), I can't seem to ...
4
votes
3answers
742 views
I can't use digital ports with my raspberry pi?
I have a raspberry pi that I really want to be able to control some motors and was thinking of this one at sparkfun: http://www.sparkfun.com/products/9670
The problem is that the Pi does not have ...
3
votes
3answers
1k views
purpose of diode in this 555 timer application
I'm a newbie in electronics.
I need to make a 555 timer base circuit(Refer to the schematic below) such that O/P pin of 555 is held LOW by default at power on, and the I/P pin is held initially at ...
4
votes
3answers
3k views
Logic Conversion 3.3V to 5V (Current Related) 74HC 74HCT
A beginner style question.
I'm attempting to perform some logic level conversions on 3.3V signals to 5V using the 74HC4050D powered at 3.3V and 74HC541 powered at 5V. Is it OK to directly connect the ...
3
votes
2answers
237 views
Flip flop/latch with isolated differential input and differential output
I am looking to make something that takes a pulse of floating voltage (say from a feedback coil of on a transformer), and maintain a differential output voltage depending on the sign of the amplitude ...
0
votes
0answers
431 views
RN-41 bluetooth module not transmitting data
I'm trying to connect a pic to an rn-41 bluetooth module. I'm not the person who designed the PCB, so I can't answer exactly why the circuit is the way that it is instead of using the voltage divider ...
3
votes
1answer
187 views
Oscilloscope acquisition frequency
I have an FPGA design and the FPGA design has a signal called start which is always high. Here is how it works. I use the computer to send data over RS232 to FPGA, the start signal drops for a cycle ...
