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182 Threads found on Analog Ground Digital Ground
Hi elec4, this question is not possible to answer, because it depend what ground it is. Number 1 priority should be to separate analog and digital. Then to avoid that bigger switching current creates ground shifts for the micro(like from the motor commutation) or noise on the micro supply (...)
Inside an IC package, what is the purpose of ground plane. Is it connected to the backplane of substrate for biasing it. Is it useful only in high frequency RF circuits or required for low frequency analog and digital circuits also.
My circuit has analog and digital grounds. digital potentiometers are placed under analog ground. These potentiometers has SPI interface which connects to the processor in digital section. Now my questions are- 1. How to feed 3.3 VCC power (...)
I have designed a PCB (4layer) as in the image. On the bottom layer, I have the analog section and all of that is connected to analog ground. 131238 On the top layer, I have some digital lines. These are tracks that are routed on the top side of the analog area. Now how should I (...)
Hi I was looking at some material on recommendations for ADCs and came across the following: "Understanding that the primary real estate consumed on the SAR converter chip is analog, it makes sense to connect the power and ground pins on the same planes. While implementing the layout you should connect AGND and DGND to the (...)
Hi, I would like to join the analog and digital grounds at only one place in the PCB using a 0E resistor in order to reduce the noise level in the design. But i stuck up with the SMPS Negative connection with the circuit. I don't know whether i need to connect the SMPS(0V) with analog section or (...)
The observed charge injection is described as crosstalk between digital input and switch in the datasheet. Your circuit is generating maximal crosstalk because you bias the switch DC level near to ground instead of half supply. All crosstalk specification are referring to the advantageous symmetrical bias situation, so we can just say that (...)
From what I have seen and know about this, if, say digital and analog ground nets - agnd and dgnd - are connected through the metal layers (with "low" resistance), then people place dummy intended metal resistors, with very resistance, between these nets, to allow LVS to treat them as different nets even though they are (...)
In general you can often use a split analog/digital plane instead of two planes on different layers. The split plane (typically connected together at a single point) helps keep the digital ground currents away from the analog circuits. That also helps force the physical segregation of the (...)
It's correct to use a 250 ohm shunt to convert 4-20 mA to 0.5-5V. But the resistor isn't connected correctly in your diagram. It has to be connected between ground and analog input pin with the sensor output current feed to junction of resistor and analog pin. You should also include the (...)
check your code and other thing make sure you have same pins in real hardware and simulations.
First of all, I'd use a four layer board, not two layers; you're just asking for trouble otherwise. Keep your analog and digital components separated. For ground plane, what I usually do is use a single plane and add cutouts to separate the analog and digital circuitry. Do a google (...)
Either voltage or current mode bias distribution has its plusses and minuses. With voltage mode you worry about ground offsets and cross-chip VT gradients. With current mode, especially very low currents (hence high net impedance) you worry about signal coupling from digital aggressors and HF power supply noise. Which of these is worse, (...)
Specs say full scale gain error is 5.2 LSbits and offset error 0.75 so worst case in theory is 6 LSbits, full scale. In practise the analog ground must not shift due to load current at the control point.
I used 0 ohm resistors many times so separate ground signals or power signals when routing PCB. For example if I have a circuit with analog ground and digital ground, on schematic use a 0 ohm resistor to connect both grounds (...)
0 V gem = 0V gemeinsam = 0V common AGND = analog ground DGND = digital ground Lotose > Lötöse = Loetoese = solder eyelet, solder lug
You forgot to post the schematic of your 555 somehow driving an LC tank. A MUX works with analog or digital signals. A shift register is digital only.
There are many previous threads about split ground planes respectively how to connect analog digital grounds. You'll find split ground plane suggestions often with reference designs, that are in terms of existing mixed signal systems rather trivial (...)
this a good design may by more than it needs. I had many problems before with high freq modulation over power especially with combined analog and digital circuits design . more safe is the better then having funny behaviour . after finishing use a scope (earthed) and measure the 24vdc and 5vdc and return of them or use a voltmeter on AC and me
A very good explanation -
U can use ferrite bead for separating analog signal from digital
Hi I wanted to use LM35 temperature sensor . The range is from -55 degree celsius to 150 degree celsius. I want to interface it with ADC 0804 for converting analog voltage into digital output. ADC has 8 bit resolution. How do I choose the reference voltage and how to do calculations for reading the complete voltage range. The output v
my problem is that I have only one power supply in my design, so how can I have two separate power sources for analog and digital part ? The tips crutschow gave concerns just to the placement scope, and mainly refers to reference ground location. Although not recommended, you can share the same Power sup
The PIC ADC input impedance is 10K. No. What is RL for? (connected from the sensor's output to ground). You are showing a connection diagram for a digital sensor. There's no load resistor required for the analog type.
The thermocouple is an analog device (not to be confused with analog Devices), a digital isolator will do you absolutely no good. Also, you don't need to ground the thermocouple, you need to actually use a differential input device. There are LOTS of solutions, here's one: AD8494.
Funny I just put this on your other post - Re: Circuit debugging help please. From past experience with analog switches, similar to what you are using, two things come to mind - 1. Ron (the on resistance) of these switches can changes drastically with supply voltage. Doubling in value from the manufacturers published headline value as the suppl
I'll try to describe my question as simply and precisely as I can. I have a mixed signal audio design consisting of analog audio circuits controlled by a microcontroller and analog switches. The analog switches control fixed routing as well as some slow speed gating and switching stuff. The analog switches must be on (...)
In an ideal world where interconnections had zero resistance and zero inductance, there would be no practical difference. The reason for separate grounds is to prevent current spikes from digital circuits from flowing in the ground connection to sensitive analog circuits. The current (...)
Usually an analog voltage could have any value between two limits Vmax and Vmin (Vmax > Vmin, but Vmax and/or Vmin can be positive or negative). A digital value could have two levels high and low or state 1 and state 0. In general (not always), a high level is close to Vcc and the low level is close to ground. Therefore (...)
Hi sree, for analog and digital separation ferrite bead used right or 0E resistor used ?? keep the bead between analog and digital ground (for separation).better post the snapshot for good understanding.
Not quite video's but here are development boards that can help with layout ideas for grounding I found them useful, There are pdf and gerber files should give you some good
I have a mixed-signal layout I need to complete. It has an 8-bit micro feeding about 16 analog switches/multiplexers which controls a bunch of analog (audio) circuitry. I know from past experience that if I'm not careful with the layout, including the placement of the power and ground planes, I can get some some transients (...)
Why do u need star ground When you have separate gnd net for digital and analog.Star ground concepts comes when you want to isolate analog and digital gnd section using single net.
I have an ADC in my system and a DAC. How should i design the ground plane, any tips? The board will be 4 layered. I have a 3.3V mcu. ADC and DAC has a 2.5 reference in common. DAC requires a 12V voltage source. digital section of the ADC can operate at 3.3V or 5V but i plan to use 5V. analog voltage supply of the ADC is (...)
For unused input pins of CMOS logic gates circuit or other digital CMOS circuit, Erm, this is the analog section, so, maybe you're asking in the wrong place? Or is that it you're customizing your own standard cells in an analog/mixed-signal design? For digital design, most engineers I know connect spare standard cells to (...)
you can measure voltage on the other side and send it as digital signal to your PIC in your side. also you can use analog Optocouplers
You will find many sources of noise when you test the design with various signals. First ensure you eliminate sources of noise you can control then worry about dithering LSB noise, unless you are dealing with repetitive waveforms. 1. Consider the cross-talk of conducted ground noise between digital and analog (...)
That's a pretty broad question. For analog layout, the main concern is noise; you want to minimize any external noise from getting into the analog circuitry. This means paying attention to component placement, routing of analog and digital signals, shielding, ground paths, etc. For (...)
Split planes are used, for example, if you want a separate analog and digital ground plane and don't want to add an additional layer in the PCB, which adds cost and complexity.
A digital ground is faster: means the digital signal arrives to its ground state faster than an analog transition.
The frequency of my circuit is 30khz. analog & digital has seperate Vdds but no seperate ground pins.analog section has onchip decoupling cap of 15pf but digital has no onchip decap. Is offchip decoupling cap for analog and digital ok?
I need your full schematic from analog driver , ADC analog/digital ground isolation, DAC output. It is clear your noise is independent of the signal input frequency but dependent of sampling clock rate lower than 250MHz. To me this is analog noise that can come from multiple sources which I (...)
When you start designing such project you need to maintain a distinct separation of split planes between the analog and digital ground planes and to keep analog traces under the analog split plane and digital traces under the digital split plane. Ideally, (...)
Hello, I am designing mixed signal board in which I use FPGA. I connect all the grounds (analog and digital) to a common ground plane and I want to feed 1.8 V analog and digital Vdd's from the same output a DC/DC converter. Although isolation is strictly (...)
Hello, First of all I hope I am writing to correct destination. My question is as the following: I am designing mixed signal board in which I use FPGA. I connect all the grounds (analog and digital) to a common ground plane and I want to feed 1.8 V analog and (...)
refer this too to get the better idea about digital to analog conversion using R-2R method Good Luck
Dear balamanikandan Are you sure that it wrote power ground and analog ground ? i think it wrote digital ground and analog ground and it referred to the star ground ? (...)
need analog and digital ground isolation ic for proxy input isolation to +3.3v microcontroller
The reason why the anlogue and digital grounds are kept separate up to the point as close as possible to the powersupply ground is to avoid any digital swithing currents (lots of them) to "lift" the analogue ground and induce noise signals (...)
Any practical circuit idea about controlling 0 to 10 volt reference by micro controller preferably by ATMEL AVR mega series as Mega8. mega48 or mega80. two digital input optically coupled, for rising and lowering the voltage. this is for variable speed DC drive or AC drive. how analog ground and digital (...)