pcb software

Formula for propagation delay of cabling in PCB The first half is information from altera. The propagation latency (tPD) is the time required to transmit a signal from one point to another. Transmission Line propagation delay is a function of the relative dielectric constant of materials. Propagation delay of micro-Strip Layout You can use formula 5 to calculate the propagation delay of the strip layout. Formula 5: Delayed propagation in the line

Shortcut Keys for protel99 and power PCB (pads layout)Shortcut for protel99 I. Principle Image Library P/P: Draw component pins P/A: draw an arc P/L: draw a straight line P/A: Draw a rectangle T/C: Create a new component T/R: Delete the component T/E: Rename the component t/W: Create a new child for the component T/T: delete a child of the component Ii. Schematic diagram CTRL + backspace: Repeat the previous operation Ctrl + backspace: cancel the pre

Note: belong to reprint Many people for the PCB traces of the reference plane is confused, often asked: for the inner layer traces, if the line side is VCC, the other side is GND, then which is the reference plane? To figure this out, you have to understand the concept of transmission lines. We know that the transmission line must be used to analyze the signal transmission on the PCB in order to explain th

A process is a dynamic description of a program, which is the smallest unit of the operating system's resource allocation (the thread is the smallest unit of the operating system execution entity). for a multi-channel program system, there may be many processes in memory, in order to facilitate the management of these processes, the operating system kernel for each created process to establish a structure to save its related information. This structure is the

High Frequency Circuit Wiring techniques in PCB Layout 1. Multi-board wiring High-frequency circuits often have a high degree of integration and a high wiring density. Using a multi-layer board is not only required for wiring, but also an effective means to reduce interference. In the PCB Layout stage, a proper selection of printing board sizes of a certain number of layers can make full use of the middle

Because COB does not have IC sealed Leadframe (Guide frame), but uses the PCB to replace, so the PCB welding mattress design Handy is very important, and fihish can only use electricity plated gold or enig (isotopes leaching gold), whether the Gold line or aluminum line, Even the latest brass lines have problems that can't be beaten up.PCB Design requirements for COB The finished surface of PC board

Address: http://blog.csdn.net/qq736934266/article/details/3582764 1. General rules1.1 Pre-division of digital, analog, DAA signal cabling areas on the PCB.1.2 numbers, analog components and corresponding cabling should be separated and placed in their respective cabling areas as far as possible.1.3 high-speed digital signal cabling as short as possible.1.4 The sensitive analog signal must be as short as possible.1.5 reasonably allocate power supplie

Top-level wiring layer of toplayer-signal Layer Bottom underlying wiring layer-signal Layer The connections of each pad are on the signal layer, that is, the connections of each component pin on the circuit board. Mechanical Layer -- Define the appearance of the entire PCB. In fact, when we say that the mechanical layer refers to the shape structure of the entire PCB Board. Keepoutlayer disallow the wirin

Which components can be made into PCB files?In PCB design, some components do not need to be made into components for the sake of speed.It is a waste of time to make components, and there is no actual component in production.As follows (continuous update ): The PCB is connected to the PCB before the manual post w

Engineers using Protel 99SE know that Protel in the PCB drawing is not support the Chinese character input, but as a factory production debugging convenience, the inevitable in the PCB to make Chinese marks, and sometimes for the purpose of explaining the Board, attention to matters such as to enter Chinese silk screen, So how do I enter Chinese when Protel does not support Chinese? This experience will be

Use the Keepout layer to determine the size of the line:Follow the steps in the diagram:1. Select the corresponding tag of the menu bar2. Select "Place lines" and draw line options3, in the black area of the PCB project can be drawn lineNow the line you draw is in the keepout layer, the line is pink!The boundary of the line is the boundary of the board"If you draw a line that is not pink, you need to re-select the Keepout layer!" 】Make the

What is PCBIn order to describe the operation of the control process, the data structure of the management and control information of the process in the system is called Process Control block, which is part of the process entity and is the most important recorded data structure in the operating system. It is the most important data structure of process management and control, each process has a PCB, when the process is created, the

The new PCB file defaults to the 2-layer board, which teaches you how to set 4 layers or even more multilayer boards. On the toolbar, click design-->layer Stack Manager. After entering the display is a two-layer board, added as a 4-layer board, usually first point top layer, then add layer, and then add layer, so it becomes a 4-layer board . See figure below. Some people do not point to add layer, but point to add plane, the difference is that the

First, preface:The so-called interaction is such, in the schematic click on a component, in the PCB diagram is selected, so that the component just lead into the PCB layout of the components can provide us with great convenience.Second, the premise:Importing components in the PCB is this way: Where the path is the path where the schematic is located.

Transferred from Zhang Fei actual combat electronic public numberGeneral principles of PCB cablingShortest path and reduced interferenceThe overall process of PCB cabling is as follows:1 understand the manufacturing specifications of manufacturers-line width, line spacing, over-hole requirements and layer requirements;2 Determine the number of layers and define the functions of each layer;3 Design Cabling r

(1) role of the process control block-the process has a unique entity; Because the process control block records the existence and characteristics of the process, the PCB and the process are born to death. When a process is created to establish a PCB for it, the process is revoked, the system will be subject to its PCB. The OS controls the process according to t

Label: HTTP Io strong SP Div C on r ef 1 feet = 12 inch 1 inch = 1000 mill Mil 1mil = 25.4um 1mil = 1000uin (MIL ears sometimes become British) 1um = 40uin (some companies call micro-inches as microphones, but they are actually micro-inches) 1 oz = 28.35g/square foot = 35 microns H = 18 microns 4mil/4mil = 0.1mm/1mm mm linewidth 1asd = 1 AMPS/square meters = 10.76 AMPS/square feet 1 AM = 1 amps min = 60 couplet is mainly used for precious metal plating such as gold plating 1 square me

PCB cabling procedure Reprinted from: http://blog.21ic.com/user1/6960/archives/2011/83333.html I. Circuit Board Design ProcedureGenerally, the most basic process of designing a circuit board can be divided into three steps.(1). Circuit Principle The schematic design of the circuit diagram is mainly the schematic design of protel099. System (Advanced schematic) to draw a circuit schematic. In this process, make full use of the various sc

When we conduct PCB cabling, we always face two or three kinds of situations on one board. The silly practice is of course, regardless of the case of November 21, copper is applied as long as it is the ground. This is not a problem for low-speed boards or boards that are insensitive to interference. Otherwise, the Boards may not work properly. Of course, if there are many places on a board, even if the Board has no requirements, but from a rigorous an

Altium Designer's PCB footprints are often seen in the same package, such as the IPC low density (lower density), IPC medium density (medium density), IPC high density (dense), such as TSSOP16, Why do you say that? IPC is the abbreviation for the American "Printed Circuit Board Association" ("the Institute of printed circuit").The "Printed Circuit Board Association" was renamed several times, but the IPC abbreviation has remained unchanged. IPC has de