etch pcb

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

1. File-->page SetupPrinter paper A column is the printing paper settings, no longer wordy.The main is the scaling column: ScaleMode selection: ScaledprintThe following scale fills 1, which represents 1:1 of the proportional print. such as 1:2, then click the Advanced tab in Figure 1 to enter the print content settings.Under the Printoutlayers project, remove the top overlay (right-click-->delete)The following is shown in Project Setup 2.I do the general is a single-layer board, so, generally on

The actual results of the PCB effect (note slot edge) in the different layers of the hole shape are drawn in different layers of the slot shape (note the slot edge)Many friends asked in the use of Altium designer PCB design, want to open a slot on the board or dig a hole how to operate, is the use of keep-out layer or mechanical layer, today, here to answer, both in the actual operation are used (and large

Last Update Time: 2010-02-06 09:56:45 There is a horn socket in the Red Circle : After the memory is unplugged, there is still a layer of stuck Plastic Parts blocking the circuit board near the horn Outlet Take a picture of the opening part of the plastic slice as follows: Should it be a BIOS battery? I split the black plastic hard shell at the place where I inserted the headset. Can I see it (the next two pictures)? I wonder if this will affect the speaker's voice? Th

special instructions, in addition to the shape to give an effective shape, such as the inner groove, and the inner groove at the intersection of the outer shape of the line should be deleted, no leakage of the groove, design in the mechanical layer and the keepout layer groove and hole is generally based on the production , if you need to process into a metal hole, please special remarks.3, if the most prudent way to do metallization slots is to put together multiple pad, this practice must be

 Author: Wang Huidong, a hi-tech team member In the "Skin of the PCB," the article, we have proposed when the thickness of the plate in 1.6mm and above, how to avoid the use of false eight layer of the stack, resulting in increased PCB costs. I feel the answer is very enthusiastic ha, it seems that the problem is still more typical. Would like to intercept some of the answers put here, but the relations

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

Label: show only one layer1 SHIFT + s this shortcut can highlight the current layer and make other layers gray, see: 2. Hide a specified layer In the lower-right corner of the figure, right-click and an option bar will pop up. Select hide layers to select the layer you want to hide. 3. Right-click any position in the PCB diagram of the specified layer in view deployments and choose Options> boardlayers colors. On the board lay

When walking multilayer board, often need to hit the hole, then how to classify the hole? and look down.(1) Through-hole: this hole through the entire circuit board, can be used for internal interconnection or as a component of the installation of the locating hole (for connecting layer; Creating a drilling file, punching on the PCB and electroplating in the hole, usually much larger than the signal line);(2) Buried hole: refers to the printed circuit

1 Open WindowPADS inside open window is directly put copper skin in the solder layer inside is open window, but also can put a pad so fast and convenient is open window. Generally choose to put a pad is not prone to error.2 when there is an error, we need to turn all the layers open. There may be some network to pull the other layer, but the network is not connected. Therefore, in the detection of PCB connectivity, will be error. This time you need to

In the previous section, the design steps for PCB principles are described in one example, and this section further introduces some of the techniques in the design.Shield : place->directive (instruction)->compile mask to block block diagrams that are not usedAdd rule : Place->directive->paremeterset You can add PCB design rules to your schematic diagramEg: Add a patemeterset, as follows:650) this.width=650;

, 300mV noise needs to be filtered and attenuated to 50mV, which means that the magnetic beads to be divided into 250mV, assuming the load 50Ω,RAC/RL = 250/50, where RL = 50ω, get Rac = 250Ω;(2) power supply rated current 300mA, derating coefficient according to 0.75, then select the minimum rated current not less than 300ma/0.75= 400mA of magnetic beads;(3) The IC supply voltage must not be less than 3.0V, then the maximum voltage drop on the DC resistance RDC on the bead should be less than 0.

ring and the magnetic beads should be used. Their resistance to the high-frequency components in the line is about 10 to several hundred Ω, so it does not play an obvious role in the high-impedance circuit, it will be very effective in Low-Impedance Circuits (such as power distribution, power supply, or RF circuits. Iv. ConclusionFerrite is widely used in EMI control because it can degrade at a high frequency and make the low frequency pass through without any obstacles. Magnetic rings/magneti

Summary of PCB multilayer Design Reprinted: PCB multi-board design suggestions and examples (, 12) Design requirements: A. The component plane and welding plane are complete ground planes (shielded ); B. There is no adjacent parallel wiring layer; C. All signal layers should be adjacent to the ground plane as much as possible; D. The key signal is adjacent to the formation and does not span the