Három tipp a PCB tervezési kockázat csökkentéséhez

A nyomtatott áramköri lapok tervezésével kapcsolatos kockázatok csökkentésének számos módja van. Ezek közé tartozik például az összes alkatrész azonos irányba történő orientálása és a rétegátmeneteknél több átjáró használata. Más módszerek közé tartozik az analóg és digitális áramkörök elkülönítése, valamint az oszcilláló áramkörök hőhatástól való távoltartása.

Orienting components in the same direction

PCB design risk is minimized by orienting components in the same direction. This practice helps minimize assembly and handling time, and reduces rework and costs. Orienting components in the same direction also helps reduce the likelihood of a component being rotated 180 degrees during testing or assembly.

Orientation of components starts with footprint construction. An incorrect footprint can lead to miss-connected parts. For example, if a diode is oriented with its cathode pointing in one direction, the cathode could be connected to the wrong pin. Also, multiple-pin parts can be installed in the wrong orientation. This can cause the parts to float on the pads or stand up, which causes a tombstoning effect.

In older circuit boards, the majority of components were oriented in one direction. However, modern circuit boards must take into account signals that move at high speeds and are subject to power integrity concerns. In addition, thermal considerations must be addressed. As a result, layout teams must balance electrical performance and manufacturability.

Using multiple vias at layer transitions

While it is not possible to eliminate vias at layer transitions completely, it is possible to minimize the radiation from them by using stitching vias. These vias should be close to the signal vias to minimize the distance the signal travels. It is important to avoid coupling in these vias, as this compromises the integrity of the signal while in transit.

Another way to reduce PCB design risk is to use multiple vias at layer transitions. This reduces the number of pins on a PCB and improves mechanical strength. It also helps reduce parasitic capacitance, which is particularly important when dealing with high frequencies. Additionally, using multiple vias at layer transitions also allows you to use differential pairs and high-pin-count parts. However, it is important to keep the number of parallel signals low, in order to minimize signal coupling, crosstalk, and noise. It is also recommended to route noise signals separately on separate layers in order to reduce signal coupling.

Keeping heat away from oscillatory circuits

One of the most important things to keep in mind when designing a PCB is to keep the temperature as low as possible. Achieving this requires careful geometrical arrangement of components. It is also important to route high-current traces away from thermally sensitive components. The thickness of the copper traces also plays a role in PCB thermal design. The copper trace thickness should provide a low impedance path for current, as high resistance can cause significant power loss and heat generation.

Keeping heat away from oscillatory circuitry is a critical part of the PCB design process. For optimum performance, oscillator components should be placed near the center of the board, not near the edges. Components near the edges of the board tend to accumulate a lot of heat, and this can raise the local temperature. To reduce this risk, high-power components should be located in the center of the PCB. Furthermore, high-current traces should be routed away from the sensitive components, since they can cause the heat to accumulate.

Avoiding electrostatic discharge

Avoiding electrostatic discharge while designing PCBs is an essential aspect of electronic engineering. Electrostatic discharge can damage the precision semiconductor chips inside your circuit. It can also melt bonding wires and short-circuit PN junctions. Luckily, there are many technical methods to avoid this problem, including proper layout and layering. Most of these methods can be carried out with very little modification to your design.

First, you should understand how ESD works. In a nutshell, ESD causes a massive amount of current to flow. This current travels to the ground through the metal chassis of the device. In some cases, the current can follow multiple paths to the ground.