The same goes for many digital systems that manipulate data in parallel. Three important points in bus routing are designing for consistent trace impedance, proper termination, and a tight ground return path to minimize loop inductance. There is another important point to consider, which is trace length matching for parallel buses.

Embedded clocks, where a clock signal is encoded in the first few bits of your bitstream, do not incur problems with clock routing in PCB bus routing. This is because each IC contributes some jitter on the signal traces, and jitter adds in quadrature. Furthermore, each IC has some delay, and the clock lines from your common clock source need to be delay matched to account for the accumulated propagation delay.

Suppressing jitter in the clock with a PLL is possible but not really practical, especially once we consider round-trip clocking on a bi-directional bus.

altium bus index

As digital systems have become more complex, standardized ICs have moved to a source-synchronous or embedded clock scheme. Even at low data rates, you should try to minimize vias on your bus lines to prevent impedance discontinuities.

If you do use vias on your bus lines, you may need to stagger your vias along the length of the trace in order to make enough room for the vias. With differential pairsyou can still get away with some slight via separation as long as you arrange the vias symmetrically along the pair.

When using low level devices 3. This regards the use of degree or right angle turns when routing signals in a bus or in any other situation. The discussion applies just as much to bus routing as it does to working with a single trace.

When routing a bus, you will most likely need to use right angle bends at some point. Most designers will state that you should never use right angle turns in a PCB layout due to the EMI that is created at the corner, and this would appear in a bus as well. Once a bus is broken out into individual traces, it follows logically that strong crosstalk would appear in a trace nearby the right angle corner. It is also said that a right angle bend causes the signal to reflect back towards the source.

Mathematically, there is an impedance mismatch between the trace and free space simply due to refractive index contrast. Whenever you have an impedance mismatch, you have the potential for reflection and resonance; this is the case in any structure in which a wave propagates.

However, whether the resonance can be supported as a standing wave, which would produce strong EMI and crosstalk, depends on the dimensions of the structure in comparison to the frequency of the travelling signal either digital or analog.

The practical reason some designers advise against right angle bends is their manufacturability. Corners can form acid traps in a PCB, where the surface tension of the etchant solution confines the etchant at the corner. This is more of a problem in tight corners, where a trace branches off at an acute angle. When etchant gets caught in an acid trap, it can cause overetching, which would increase the surface roughness of the trace.

Today, this is a problem that is primarily seen with low-quality overseas manufacturers. The half-wavelength associated with the signal use the knee frequency for digital signals can generally be used as a benchmark for examining whether a forced resonance will arise in a given structure.

In the case of a right-angle turn, the quarter wavelength should be used as you have an open structure. For a digital signal with 20 ps rise time Even if we consider a generous trace width of 0. For practical purposes, you can effectively ignore the problems with right angle bends in PCB bus routing as any radiated EMI will be weak in most situations.

With very high frequency analog signals, there is a greater potential for resonances as the width of these traces tends to be much wider. Although datasheets may seem to have some inconsistent information, they will generally tell you the allowed tolerances when routing a signal bus.

Your interactive routing tools can check your board as you route, ensuring your device will work as intended. These tools automatically check your layout against your design rules as you create your board. With the pre-layout and post-layout simulation toolsyou can examine signal integrity in your bus design before moving to manufacturing.Parent category: Violations Associated with Buses.

Tutorial 2 for Altium Beginners: How to create footprints

Default report mode:. This violation occurs when the index of a constituent net connected to a bus lies outside the range specified by the net to which the bus is associated. If compiler errors and warnings are enabled for display on the schematic enabled on the Schematic - Compiler page of the Preferences dialog an offending object will display a colored squiggle beneath it.

A notification is also displayed in the Messages panel in the following format:. With the violation selected in the Messages panel, use the Details region of the panel to quickly cross probe to the net label associated with the offending net and either amend the index of the net so that it lies within the correct range, or rename the net altogether. The latter would be typical if you have named the net by mistake and it is not a constituent of the net transported by the bus object.

If would like to speak with a representative, please contact your local Altium office. Download Altium Designer Installer. You may receive communications from Altium and can change your notification preferences at any time.

If you are not an active Altium Subscription member, please fill out the form below to get your free trial. Just fill out the form below to request your Student License today. Upverter is a free community-driven platform designed specifically to meet the needs of makers like you. Click here to give it a try! Using Altium Documentation. Parent category: Violations Associated with Buses Default report mode: Summary This violation occurs when the index of a constituent net connected to a bus lies outside the range specified by the net to which the bus is associated.

Notification If compiler errors and warnings are enabled for display on the schematic enabled on the Schematic - Compiler page of the Preferences dialog an offending object will display a colored squiggle beneath it. A for net A8connected to a bus associated to net A[ NetIndex is the erroneous index of the constituent net e.

Recommendation for Resolution With the violation selected in the Messages panel, use the Details region of the panel to quickly cross probe to the net label associated with the offending net and either amend the index of the net so that it lies within the correct range, or rename the net altogether.

Printer-friendly version. Found an issue with this document? Contact Us Contact our corporate or local offices directly. Connect to Support Center for product questions. Created using Figma.

First off, are you or your organization already using Altium Designer? In that case, why do you need an evaluation license? I need the latest Altium Designer installer. I want to evaluate the latest features. I want to view a design file. Got it. Click the button below to download the latest Altium Designer installer. Please fill out the form below to get a quote for a new seat of Altium Designer.

Why are you looking to evaluate Altium Designer?The Bus dialog. This dialog allows the designer to specify the properties of a Bus object.

A bus is an electrical design primitive. It is a polyline object that represents a multi-wire connection. The Bus dialog can be accessed prior to entering placement mode, from the Schematic — Default Primitives page of the Preferences dialog. This allows the default properties for the bus object to be changed, which will be applied when placing subsequent buses.

Bus dialog - Graphical tab. Use the dialog's Graphical tab to modify graphical properties of the bus object. Bus dialog - Vertices tab. Use the dialog's Vertices tab to edit the individual vertices of the currently selected bus object. You can also add new vertices to the bus, or remove selected vertices altogether. If would like to speak with a representative, please contact your local Altium office.

Download Altium Designer Installer. You may receive communications from Altium and can change your notification preferences at any time. If you are not an active Altium Subscription member, please fill out the form below to get your free trial. Just fill out the form below to request your Student License today. Upverter is a free community-driven platform designed specifically to meet the needs of makers like you.

Click here to give it a try! Using Altium Documentation.

Illegal Bus Range Values

Summary This dialog allows the designer to specify the properties of a Bus object. For information on how a placed bus object can be modified graphically, directly in the workspace, see Graphical Editing.Professional unified design system, high productivity stress-free environment and native 3D PCB editor. If would like to speak with a representative, please contact your local Altium office.

Download Altium Designer Installer. You may receive communications from Altium and can change your notification preferences at any time. If you are not an active Altium Subscription member, please fill out the form below to get your free trial. Just fill out the form below to request your Student License today. Upverter is a free community-driven platform designed specifically to meet the needs of makers like you. Click here to give it a try! Using Altium Documentation. Learn More.

Subscribe to RSS

Team-based PCB design solution for data management, collaboration, and process management. Single source for component management and collaboration with your mechanical design team.

Create and deploy custom extensions and business system integration for Altium products. Contact Us Contact our corporate or local offices directly. Connect to Support Center for product questions. Created using Figma. First off, are you or your organization already using Altium Designer? In that case, why do you need an evaluation license? I need the latest Altium Designer installer. I want to evaluate the latest features. I want to view a design file. Got it. Click the button below to download the latest Altium Designer installer.

Please fill out the form below to get a quote for a new seat of Altium Designer. Why are you looking to evaluate Altium Designer? I like to design PCBs as a hobby.

You came to the right place! Please fill out the form below to get your free trial started. Great News! You can download a free Altium Designer Viewer license which is valid for a 6 months. Please fill out the form below to request one.Schematic Editor object properties are definable options that specify the visual style, content and behavior of the placed object.

The property settings for each type of object are defined in two different ways:. If would like to speak with a representative, please contact your local Altium office. Download Altium Designer Installer. You may receive communications from Altium and can change your notification preferences at any time. If you are not an active Altium Subscription member, please fill out the form below to get your free trial.

Just fill out the form below to request your Student License today. Upverter is a free community-driven platform designed specifically to meet the needs of makers like you. Click here to give it a try! Bus Properties. Using Altium Documentation. Contents Properties Vertices Properties panel only.

While the options are the same in the dialog and the panel, the order and placement of the options may differ slightly. In the below properties listing, options that are not available as default settings in the Preferences dialog are noted as " Properties panel only".

Printer-friendly version. Found an issue with this document? Contact Us Contact our corporate or local offices directly. Connect to Support Center for product questions. Created using Figma. First off, are you or your organization already using Altium Designer?

In that case, why do you need an evaluation license? I need the latest Altium Designer installer. I want to evaluate the latest features.Parent category: Violations Associated with Buses. Default report mode:. This violation occurs when the index of a constituent net connected to a bus lies outside the range specified by the net to which the bus is associated. If compiler errors and warnings are enabled for display on the schematic enabled on the Schematic - Compiler page of the Preferences dialogan offending object will display a colored squiggle beneath it.

Hovering over the object will display a pop-up hint that summarizes the violation. A notification is also displayed in the Messages panel in the following format:. With the violation selected in the Messages panel, use the Details region of the panel to quickly cross probe to the net label associated with the offending net and either amend the index of the net so that it lies within the correct range, or rename the net altogether.

The latter would be typical if you have named the net by mistake and it is not a constituent of the net transported by the bus object.

altium bus index

If would like to speak with a representative, please contact your local Altium office. Download Altium Designer Installer.

altium bus index

You may receive communications from Altium and can change your notification preferences at any time. If you are not an active Altium Subscription member, please fill out the form below to get your free trial. Just fill out the form below to request your Student License today. Upverter is a free community-driven platform designed specifically to meet the needs of makers like you. Click here to give it a try! Using Altium Documentation.

Notification If compiler errors and warnings are enabled for display on the schematic enabled on the Schematic - Compiler page of the Preferences dialogan offending object will display a colored squiggle beneath it.

NetIndex is the erroneous index of the constituent net e. Recommendation for Resolution With the violation selected in the Messages panel, use the Details region of the panel to quickly cross probe to the net label associated with the offending net and either amend the index of the net so that it lies within the correct range, or rename the net altogether. Printer-friendly version.Parent page: Schematic Objects.

A Bus is a polyline object that is used, in conjunction with other connected objects, to define the connection of multiple nets. After launching the command, the cursor will change to a cross-hair indicating Bus placement mode. Placement is made by performing the following sequence of actions:.

When placing a Bus there are three 'manual' placement modes, two of which have corner direction options. The modes specify how corners are created when placing buses and the angles at which buses can be placed.

Placing a Bus segment in Auto Wire mode, as indicated by the dotted path line. When placed rightthe Bus path will automatically avoid obstacles. The path of the route will be the most efficient possible, while avoiding existing placed objects on the sheet. Press Tab while in this mode to configure applicable options in the Point to Point Router Options dialog. Along with its snap to grid feature, the schematic editor also supports snapping to available electrical connections.

When an object being placed, such as a Bus, falls within a definable snap distance of a valid electrical connection, the cursor will jump to that electrical 'Hotspot' shown as a red cross.

The electrical snap point is indicated by a red cross. Selected Bus, ready for graphical editing. With the Bus selected, click on a segment to individually select that segment.

This Bus 'sub-selection' is distinguished by the associated editing handles becoming red in color. Individual segment sub-selection.

The associated vertices for the segment can then be edited directly using the SCH List panel, with any changes appearing immediately on the schematic. Panel page: Bus Properties. This method of editing uses the associated Properties panel mode to modify the properties of a Bus object. The Bus mode of the Properties panel. During placement, the Bus mode of the Properties panel can be accessed by pressing the Tab key. Note that the panel includes a Vertices tab, where you can edit the individual vertices of the currently selected Bus object — Index 1 is the first placed vertex.

After placement, the Bus mode of the Properties panel can be accessed in one of the following ways:. The Properties panel supports multiple object editing, where the property settings that are identical in all currently selected objects may be modified.

Used in conjunction with appropriate filtering — by selecting object types using the panel's Include optionsor by using the applicable Filter panel or the Find Similar Objects dialog — it enables the display of just those objects falling under the scope of the active filter.


Comments

Leave a Reply

Your email address will not be published. Required fields are marked *