Questions tagged [ground-plane]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
29
votes
5answers
8k views

Should I really divide the ground plane into analog and digital parts?

I am about to design my first PCB as part of my graduation project. Of course, as the first step, I try to learn as much as possible. A part of the research I found this 3 part article, that suggests ...
16
votes
4answers
2k views

Reasons not to fill unused board area with power planes instead of ground planes?

On the (two-layer) board I'm designing, I have a relatively large unused area. Instead of just pouring it with ground on both sides, I'm considering filling it with Vcc on one side and ground on the ...
11
votes
4answers
2k views

Why exactly is it discouraged to gap the ground plane?

From time to time I hear (and read) that it is not good to make separate Gnd planes for digital and analog circuit parts. It's all summarized in this rule of thumb: "Don't split the Gnd plane, don't ...
11
votes
3answers
297 views

How to minimize impedance from capacitor to Gnd and Power planes

I'm trying to minimize the impedance from my capacitors to the Gnd and Power planes. 1. Via positioning I've learned from several sources that the best via positioning is close to each other. This ...
10
votes
1answer
481 views

Purpose of exposed ground pads

I have a Beckhoff EL2008 8-channel digital output terminal that I took apart because I'm using an ASIC that is inside the module, Beckhoff's ET1200. There is essentially a ring of ground pads,some ...
8
votes
1answer
581 views

15MHz photodiode PCB, feedback requested

I've developed a 2-layer 15MHz photodiode amplifier board. The first stage is a transimpedance amplifier using AD8065. The second stage is using a current-feedback amplifier, THS3091. Power is +/-12V ...
7
votes
4answers
6k views

Should there really be 1 MΩ resistance between an anti-static wrist strap and a pc?

My previous question: what exactly is grounded through motherboard standoffs? The answers suggest that a PC case is grounded in 2 ways: To the ground plane of the motherboard, through the brass ...
7
votes
1answer
744 views

The curse of the ground loop

Sometimes it feels like a ground-loop is inevitable. Please follow along the following thought-experiment. It would be wonderful if you could provide solutions to the issue described. Imagine a board ...
7
votes
3answers
953 views

What are the different grounds on a PCB?

I am working with boost converters recently. I have problem which you can find here. After going through the datasheet several times I encountered the special focus on the ground plane. It talks about ...
7
votes
1answer
2k views

PCB antenna: ground plane layers and dimensions?

I'm using an Inverted-F antenna on a Bluetooth Low Energy peripheral/device I'm designing and I'm not sure how I should design the ground plane. The ground plane should not be "too big" nor "too ...
6
votes
3answers
3k views

Should there be any PCB ground plane under a 16 MHz oscillator?

For a 2-layer PCB, should there be a ground plane under a 16 MHz oscillator? From this PDF document, http://www.nxp.com/assets/documents/data/en/application-notes/AN2500.pdf, it shows the following ...
6
votes
1answer
209 views

Its ok use different layers for power?

For example in a double side board I'm using one layer as gnd and the other layer as power, and then I route the whole circuit inside the planes. Is that ok? Because I saw that usually both sides are ...
6
votes
1answer
835 views

Additional signal plane vs lots of vias

I have a circuit that I am currently designing using a 4 layer PCB (signal, ground, power, signal). The PCB has rather a lot of vias to route the signals around the board (there are size constraints, ...
6
votes
3answers
4k views

For a 4 layers PCB (with ground plane), covering with ground polygon on Layer 1&4 necessary?

For a single or double layered PCB board, usually I will cover all the empty spaces in the layout with Ground. This is the 1st time I am designing a 4 layer PCB layout. Layer 1: top signal (high ...
6
votes
2answers
883 views

Placement of RF module for better performance

I am using a standard RF module (i.e., Bluetooth-module-on-PCB), which has a PCB-trace-type anntena. It is in turn to be soldered onto my main PCB. The whole thing will be powered by a standard Li-ion ...
6
votes
1answer
3k views

What's the purpose of the ground plane?

What's the purpose of the ground plane? I guess it's a pretty basic question and I tried to understand it by reading http://en.wikipedia.org/wiki/Ground_plane#Printed_circuit_boards but I still don't ...
6
votes
2answers
1k views

How on earth shall I design the ground planes for mixed signal circuits, split or not?

Our circuit is like following: There are four layers, including top, power, ground and bottom. My way of grounding: I follow the instruction by Maxim: https://www.maximintegrated.com/en/app-notes/...
5
votes
1answer
1k views

Can a ground plane be used as a current return path? (DC only, no signals, no AC)

I'm creating an adapter which hosts two connector types and simply routes two connections from one connector into the other. Only two traces/connections are used; Vcc (about 6v) and GND Operating ...
5
votes
3answers
8k views

'Unrouting' a ground plane on Eagle

I have been using Eagle for quite a while now but there is one thing that continues to bother me while I am using it. I have made the ground plane cover the shape of the board, however, when I am ...
5
votes
1answer
697 views

Stripline reference plane discontinuity in reference design

According i.MX6 SMART DEVICE SYSTEM of freescale layout board, it uses 8 layers, my question is about the inner layers, they are striplines with a continuos GND plane in one side but in the other side ...
5
votes
2answers
3k views

Power origin and power planes placement on PCB

Although there are many similar questions to this one, I wish to get your attention to this specific board layout. The main power on the board will be 5V, and one of the layers is dedicated for this....
5
votes
1answer
943 views

Should vias be used for every GND connection?

When making a two layer board with the bottom layer being a GND plane, should every GND pad for ICs and passives be directly connected to the GND plane using a via, or should I route all of the GND ...
5
votes
1answer
663 views

Effects of ground plane size on antenna gain

I have looked online a bit and it seems to me that the general belief is that the larger the ground plane (up to a certain extent), the better. I am trying to design a patch antenna, so I ran several ...
5
votes
1answer
551 views

Avoiding noise coupling by power switching to ground plane in multilayer PCB

I've a 4 layer PCB in which I've to layout a power switching supply mixed with digital signal circuit. My stack up is: Top Layer: component and routing (power net and signals) Internal plane 1: GND ...
5
votes
1answer
905 views

Why are there so many signal grounds for PCI Express?

PCIe connections have one to two ground contacts per differential signal pair. Why is this the case? On the boards that I have been studying, all of these pins are tied together onto the same ground ...
4
votes
2answers
270 views

Why are copper pours called copper pours?

I was adding a ground plane to a PCB layout today, and my curiosity peaked. Virtually every EDA package uses the term "Copper Pour." Why is it called a copper pour? It doesn't really make sense ...
4
votes
3answers
526 views

PCB Layout Help (with schematics!) - Split ground plane or not?

Obligatory "not an EE, just a ChemE trying to make some pressure readings for science"! Schematic attached, along with my current layout. It's a 6-channel pressure sensor using MPX4115AP sensors and ...
4
votes
2answers
884 views

AC signal and ground plane with another trace passing between - is this bad?

In learning about reducing a circuit's EMI emissions, I've learned the importance of a ground plane, in that it allows the current-return for an AC signal in an adjacent layer to flow directly under ...
4
votes
2answers
310 views

Gerber lines in ground plane

My manufacturer is asking me to remove those lines from the ground gerber layer The design was made in eagle, I've been searching information about this problem and I've found nothing, I don't know ...
4
votes
2answers
470 views

Power and Ground planes The Henry Ott way or split ground planes

Seeing a lot of mixed infomation around involving ground planes on multilayer boards. For a mixed signal mulitlayer PCB which is the preferred method? I know every board is different and it depends ...
3
votes
3answers
5k views

How does Stitching capacitor provide shortest return current path between plane splits, as we know that it blocks DC current?

I heard that Stitching capacitors are used to provide shortest return path whenever a signal is routed along the 2 power plane splits. As we know the return current path will be right under the trace. ...
3
votes
2answers
1k views

How to make a ground plane for relay PCB switching mains?

I am making a PCB board with 4 relays controlled by a PIC microcontroller as shown. The board consists of components that are working on 5V DC and the relays that are connected to 110VAC. I had a few ...
3
votes
2answers
673 views

Ground plane for a buck boost regulator circuit

I have made this circuit using TPS63031: Here is the board file: I have closely followed the layout recommendations given in the datasheet: Circuit is a little different because I am using fixed ...
3
votes
2answers
793 views

Is it necessary to separate ground planes in a PCB if there are different voltages?

I'm designing my first PCB and probably the circuit is a bit complex for my electronics knowledge. So a doubt arised while drawing the layout. The board has got a Microchip MCP73871, an integrated ...
3
votes
3answers
1k views

How do I know where to put stitching vias?

I'm working on a PCB that allows me to attach a TSSOP IO expander to a breadboard more easily for experimenting. I asked a question regarding the configuration of decoupling capacitors for an IC with ...
3
votes
3answers
671 views

Will a star-shaped Vdd net reduce ground oscillations?

One of EE.SEs famous answers advocates to use local ground-planes or -nets on ICs that generate broadband noise on power rails (like microcontrollers) in order to reduce excitation of planes as patch ...
3
votes
1answer
143 views

Shaping ground plane on a 4 layer USB Midi controller PCB

I have asked about this before but I have to admit that I didn't read enough before asking and therefore was'nt able to ask the question properly. I hope I am now. I'm designing a 4 layer board with ...
3
votes
2answers
339 views

Are thin connections between ground planes “islands” acceptable for ~0.5mA?

Is it okay to have a section of the ground plane connected to the rest of the ground plane through a thin trace as long it does not carry lots of current (.5 mA approximately)? There is an example: ...
3
votes
1answer
265 views

Why use a localized ground plane?

It is known that the return current starts following the conductors as the frequency increases: So as long as one keeps the distance between the conductors large enough there shouldn't be the need ...
3
votes
1answer
1k views

How do I design correctly ground plane separation for Texas Instruments TPS63060 IC?

I'm concluding my two-layer PCB design and my last obstacle is ground planes. Specifically, the problem is the TPS63060 IC that requires Power Ground separation from Control Ground (pin 7). That is a ...
3
votes
2answers
386 views

Extent of ground plane beneath filtered DC converter?

I'm laying out the PCB for a small and simple power supply to feed some audio amplifiers. It will feature a DC -DC converter module and I'd like to filter the output for 1) extra smoothness 2) learn ...
3
votes
1answer
1k views

Benefits of top and bottom ground pour in multilayer boards with proper ground plane layers and stackup

I'm trying to get some analytical feeling for the use of ground pours on bottom and top layer in multilayer boards with proper stackups such as (for example). Top Gnd Sig1 Power Power Sig2 Gnd ...
3
votes
1answer
471 views

Multiple ground planes with optocoupler

I'm designing a circuit that uses an optocoupler to isolate a relatively noisy H bridge from the USB circuitry also present on the board. Clearly in this case I will have two grounds - what is the ...
3
votes
1answer
2k views

Is it OK to place ground plane under transformer?

I have a large transformer (50kHz, ferrite E-core) on the PCB. I want to pass power rails under it on the bottom layer. Should I place a large ground plane on the top layer to shield these power rails ...
3
votes
1answer
179 views

Should the ground plane of a noisy mezzanine card be connected to the ground plane of the main card by metal mounting hardware?

I have a mezzanine card, 60 by 40 mm, mounted near one end of a main PCB, about 160 by 40 mm. This card is a known source of EMI problems and, in fact, has a metal shield over it. But, I suspect ...
3
votes
1answer
3k views

Question about analog and digital ground planes

I am using a microcontroller with an integrated DAC. On my 4 layer PCB, I have connected the digital and the analog ground planes below the microcontroller. The microcontroller and the DAC are ...
3
votes
1answer
87 views

Return Current of a 200MHz signal sandwiched between GND and split power planes

Here's my relevant 6-layer stackup: L2: GND, L3: Power, PP: 37mil, L4: Signal, core: 4mil, L5: GND I have a 200MHz signal on L4 and my assumption is that most return current will go through L5 and ...
3
votes
1answer
265 views

Shield in Inner Copper Layer

I have been designing second version of 4 Layer PCB. The PCB has connectors all over the PCB. In the first version, I had Copper Pour (I call it ...
3
votes
1answer
1k views

Ground planes on 2 layer PCB

I know there are multiple questions about this topic, but I didn't found an exact answer to my question. My situation: I'm having a 2 layer PCB. On the PCB there are multiple SMD components and ...
3
votes
2answers
1k views

Connecting Analog and Digital Grounds

I am designing a system that incorporates an FPGA, a few ADCs, and a few DACs. I am curious as to what my best options may be for grounding in my system. The FPGA is on its own daughter board, but ...