Questions tagged [trace]
Lanes of copper on a printed circuit board, for carrying current or signals between pads
181
questions
0
votes
1answer
42 views
DDR3 skew matching for microstrip and striplines
I am designing DDR3 pcb first time so I started from guide about pcb design:
https://www.youtube.com/watch?v=ZNq_Ulm8cTk#t=32m
As I understand using only stripline ...
0
votes
2answers
40 views
Logic level MOSFET gate trace length
I am using a micro-controller to switch a logic level MOSFET (the IRLR3103). The output of the MCU is 3.3V. I have a 1K resistor in series with the gate as well as a 100K pull down resistor as close ...
1
vote
0answers
47 views
Resistive heating cuircuit design
I am designing a small (10mm^2) resistive-based heater. I wish to heat a ceramic surface to about 250°C, via some high frequency AC-current. My aim to is have some sort of high-temperature PCB printed ...
0
votes
1answer
31 views
Relation ship between Track width, Impedance, Dielectric and copper thickness
I like to know the relationship between different factors like track width, impedance, dielectric and copper thickness.
After quite a reading I got to know that as the track width of a cline is ...
0
votes
1answer
25 views
Altium Design, can't change track width
I have hit 3 while tracing, I have hit shift w to open my favorites and it shows me favorites, but for some reason the program will not change the width of traces. It is stuck at 10mil. Anyone know ...
0
votes
2answers
60 views
What's the spacings specification between traces on a printed-wiring board
According to a UL/ULC standard, the spacings between traces of the PCB is specified as below table
I am quite curious about the spacings. Because there are many IC circuit components with very short ...
0
votes
3answers
54 views
Can you split track width among layers to equal one big trace?
Assume you want a trace to be able to carry 20 amps of current on 1oz copper with a temperature rise of 20. Using an online calculator this yields 12.60mm trace width.
My question is, can you split ...
3
votes
1answer
81 views
What is the reason for multiple ground connection and multiple testpoints on this PCB?
Please, have a look at the image:
The biggest pad at the top is the negative terminal of a battery holder. Through 0 Ohm resitor above it goes to a capacitor across a DC motor (not shown). Below the ...
0
votes
0answers
40 views
How to measure impedance of sensor's traces?
I'm designing a humidity sensor as a semester project and I want to measure impedance of these traces:
I don't have specialized impedance measuring instruments for this.
As I'm thinking, this should ...
0
votes
1answer
44 views
Compromising on placement or routing of decoupling cap with BGA package
As far I know there are two important points related to power-supply decoupling capacitors. First the placement be less than 3 cm from the digital IC. Second the power tracks route pass through this ...
0
votes
1answer
64 views
Is it bad practice to have power lines on a PCB instead of a plane [closed]
I am designing a PCB and am wondering what the downsides are to having a 5V trace instead of a plane.
1
vote
1answer
106 views
PCB Design - How much length can I2C lines differ by?
I am designing a PCB that uses I2C communication and was wondering how much length the SCL and SDA lines can differ by.
EDIT: Clock frequency can be anything from 95kHz to 400kHz. Is there a ...
2
votes
1answer
47 views
Why do PCI Express riser/adapter cards have electrical components?
I'm looking to make a custom PCI Express right angle adapter because the ones on the market don't work with my space constraints. Now, because it's basically an extension cable, I'd imagine it should ...
1
vote
2answers
39 views
Allowing redundant tracks in EagleCAD
I have a 2-layer PCB, where I'd like to connect the top and bottom layers of two pads with a trace.
However, when I try to connect one layer, the other layer simply disappears, as shown below, where I'...
0
votes
1answer
70 views
Serpentine PCB heater size calculation
So, I'm kinda new to the field and the time has come to design my first PCB heater. The main concept is to drive it using a Raspberry Pi and a temperature sensor as feedback.
Here is the whole ...
1
vote
1answer
43 views
Separation of same layer traces
I've seen this capacitor:
https://api.kemet.com/component-edge/download/datasheet/C0603C221JDGACAUTO.pdf
It is a 0603 capacitor with a 1000VDC rating. As I am familiar with IPC2221, this did not ...
1
vote
1answer
81 views
How can I determine the best trace width for my pcb?
In my project I use 2 external layers in air. How ever in my circuit the maximal current (Imax) in transient mode is about 70A and in steady sate it gets to 12A.
My question is, how can I know for ...
0
votes
1answer
68 views
Altium Trace, Silkscreen not solid ie only showing outline
Whilst working with Room Copy key command (D-M-C) I have inadvertently changed something which has resulted in my traces and overlays showing as their outline only.
Does anyone know what I've done to ...
2
votes
0answers
47 views
Different trace width signal transmission line
I have a really basic question. I am wondering what happens physically with the signal, if I have a change in a trace width (see picture below).
My point of view is that you have a reflection of the ...
3
votes
4answers
991 views
STM32 (SWD) printf not working
I'm new using STM32 microcontrollers, I have been trying to use the printf tracing in my code without success, anything is printed on the console. I can start a debug session, I can place breakpoints ...
2
votes
1answer
116 views
Traces over ground plane [duplicate]
Sometimes it cannot be avoided to run traces over a ground plane (bottom layer) in a two layer PCB.
I have two questions regarding this:
In the (simplified) example below, what is preferred? To use ...
0
votes
1answer
61 views
Vias or traces through two pins of e.g. resistors on a PCB?
I made the design below in KiCad. It's for me a test to see if I can solder SOT23, 0604, 0805 and 1205 components.
Someone said it is not a good idea to make traces between two pins of a component (...
0
votes
0answers
40 views
Learning designing a Arduino pcb, doubt about USB traces
what consideration should I have for the USB section. How do correctly the usb traces? What means this curves?
This is my reference schematic and due board.
Thanks
0
votes
0answers
24 views
CAN Bus Isolated Ground Trace Layout
I'm using an ADM3053 isolated CAN transceiver in my design, which, due to layout constraints, is located ~6" away from the board CAN connector. The CAN_H and CAN_L traces are routed as a 100Ohm ...
0
votes
1answer
44 views
How critical is it for SN65HVD1780DR A/B Differential signal lines to have matched trace length?
How critical is it for the A/B differential signal lines of SN65HVD1780DR to have matched trace lengths on PCB?
2
votes
2answers
244 views
Reduce impedance for power traces of a decoupling Cap when ground planes are not directly under
I am using an SHTC3 temp and humid sensor to send readings using I2C lines to the MCU.
Based on the datasheet for SHTC3 to make sure the sensor is reading ambient temp without the interference of the ...
3
votes
3answers
286 views
Surge Current on PCB
When designing a PCB, do you need to worry about the inrush/surge current or just the continuous/RMS current on the board? Everything I have seen including IPC documentation is for continuous current....
3
votes
4answers
629 views
Beyond what is recommended by fabricators, how far should traces be from SMD pads?
Having followed a fabricator's DRC (this case being OSHPark), this distance between an SMD pad and a trace is considered acceptable (see attached images).
However, I wanted to inquire about what the ...
2
votes
2answers
735 views
PCB Trace Repair (Need to keep track shape?)
Need to repair a trace on my PCB. The burnt trace has a hairpin turn on it. Instead of following the same hairpin shape, can I just bridge across the undamaged points at the bottom? And also, the ...
0
votes
2answers
237 views
Why sometimes some PCB designer add extra traces to connect two pin to each other?
I've checked a PCB board which has designed by very famous company and I saw something weird.They connected two pin to each other 2 times and from the top and the bottom of the board I am going to ...
2
votes
2answers
123 views
Replacing burnt traces
I have a tiny PCB that I've been working on and off of for a while now. I received it with leaking batteries, and it had corroded some of the traces off the board. Most recently, I tried redrawing the ...
5
votes
1answer
623 views
Routing large RF trace to small SMD pad
I am designing an RF board in Altium where due to the dielectric selected and its thickness, the trace width for a 50 ohm characteristic impedance is thicker than some of the SMD component pads. What ...
4
votes
2answers
548 views
Routing thick high current traces to small SMD pads?
What is the best practice for routing high current traces through the pads of small 0603 components?
I have a wide high current trace which that passes through a 0603 decoupling capacitor.
Initially ...
1
vote
3answers
772 views
Minimum PCB Trace width with SMD components and Autorouter problem
I would like to receive some suggestions from you about the trace width for my PCB.
I'm using some SMD components (ATmega328p TQFP32 and FT232), the main power is 5VDC at maximum 2A. I use also a ESP ...
0
votes
0answers
40 views
Analogue Video Trace Matching
I'm working on an analogue audio, video and sync board for my Dreamcast. Something I've been wondering about is the tolerance for analogue video, specifically RGB, in regards to the delta for trace ...
2
votes
3answers
208 views
How to fix incorrect routing to SMD transistor terminals
I've got a doozy of a situation:
On this circuit I had made, I routed an IRL530N D2Pak transistor with Source and Gate switched....the large heat pad should be the gate input, but instead I routed it ...
0
votes
0answers
50 views
Antenna trace 135 degree bending
I designing PCB for SIM7600CE with space constraint.Here, I placing filter matching and the antenna section through 135 degree angle traces (GREEN MARKING).Is it Okay?Can I have any PCB guidelines?
...
25
votes
6answers
5k views
Is it OK to route a trace through a pad?
Will I have any trouble routing the traces in this way? (VCC and GND)
Is it OK considering that the entire circuit current is under 50mA?
2
votes
1answer
120 views
DDR Trace Length Inside Package from Simulation Model
The DDR4 in question is a Micron MT40A512M16JY. From the vendor site, you can get the datasheets, specs, sim models. I assume from the sim models you should be able to see the trace length of each ...
1
vote
1answer
192 views
DDR3 trace length: need a confirmation
I am reading JEDEC DDR3 specification, and so many other documents on DDR3 guidelines.
Before I move to pcb prototyping, I just need a confirmation.
I connected all my lines, respected the grouping, ...
1
vote
0answers
37 views
Slewed fpga drive rise time on pcb to enet phy
What can cause rise times to be slewed from an fpga to an enet Phy? Can it be trace capacitance?
This is a high density 14 layer board . Traces route from fpga to ribbon connector, along a short ...
0
votes
0answers
41 views
Faster 8051 not taking the slower 8051 pin status correctly
I'm trying to do a rather simple data transaction between two 8051 microcontrollers using a variant of the SPI protocol. The large one is a slave and the small one is a master.
The documentation for ...
0
votes
1answer
37 views
Antenna CPW internal layer
I see on the internet showing CPW( coplanar waveguide) always placed on TOP layer with ground underneath. This is what I usually do.
Is it possible to place a CPW in an internal layer? if so what ...
1
vote
0answers
113 views
How far away can DDR3 memory be placed from the SoC?
I thought of an idea where i have a pcb with a soc on it, and a seperate one with the DDR3 memory that can snap into each other.
This way i can replace or debug specefic parts of the system and have e....
2
votes
1answer
99 views
How to set the width of all the traces together to the desired value before using autoroute option in Autodesk Eagle?
How to set the width of all the traces together to the desired value before using autoroute option in Autodesk Eagle?
every time I use autoroute, the trace width is by default set to 0.0154mm. I have ...
0
votes
1answer
478 views
Is there available differential impedance calculation for this stripline configuration?
I am trying to calculate the differential impedance of a differential pair in a 4-layer PCB as follows:
Layer: Low speed signal
Layer: Power plane
Layer: Differential pair
Layer: Ground plane
I am ...
0
votes
0answers
74 views
Oscilloscope Trace Appear Delayed
I saw a thing on my GDS-1052-U oscilloscope: if I set the time base to 25mS/div there appear a delay of the signal on the screen. So, when I rotate the knob for the time base to 25mS/div, there is a ...
3
votes
1answer
336 views
How can I account for package trace length in KiCAD?
The documentation I got for the MCU provides "package trace length" (in micrometers) as well as "package trace delay" (in picoseconds). For example like this - 6535.15 um package trace length for M_DQ[...
8
votes
2answers
1k views
thickest pcb track before hitting ridiculousness in digital circuits
Ok, you can call me ridiculous.
But, When I make PCB's, I learned myself to get into a habit into making thick PCB traces for every wire including those that others would use maybe a 5 - 8mil width.
...
1
vote
3answers
1k views
Is it okay to use wider trace than actually required while designing a PCB?
I used eagle to recently, design a board with all trace widths 30 mills except a few as 20 mills. I actually didn't require traces this wide and 15 mills would probably have been enough. Does this ...
