High Frequency PCB is a type of PCB which is widely used in applications involving special signal transmission between objects.

It is available in frequency range of 500MHz to 2GHz and is an ideal choice for mobile, microwave, radio frequency and high speed design applications.

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Radio frequency printed circuit boards (RF PCBs) are an exciting, fast growing sector of the PCB manufacturing industry. The engineers at AiPCBA can assist you with every step of the fabrication and assembly process, including material selection and key RF PCB manufacturing challenges to be aware of

RF is radio frequency, which refers to RF signal with high frequency. According to the performance requirements of the circuit board, it can be ordinary FR4 epoxy glass fiber, or it can be a special microwave substrate such as Teflon. In the PCB design of low power RF, the standard FR4 material (good insulation, uniform material, dielectric constant ε = 4, 10%) is mainly used. RF PCB, each component should be closely arranged to ensure that the wiring between the components is the shortest. For a PCB with mixed signal, RF part and analog part should be far away from digital part (the distance is usually more than 2 cm, at least 1 cm), and the grounding of digital part should be separated from RF part. When selecting components to work in high frequency environment, surface mount devices should be used as much as possible. This is because surface mount components are generally small in size and have short pins..

Signal integrity or SI is a set of measures of the quality of an electrical signal. In digital electronics, a stream of binary values is represented by a voltage (or current) waveform. Over short distances and at low bit rates, a simple conductor can transmit this with sufficient fidelity.

The main function of signal integrity is to prevent signal distortion in the process of transmission, such as delay of rising edge and falling edge, overshoot, etc. In fact, we want the signal to be able to analyze the signal completely at the receiving end. There is also the reduction of crosstalk to other signal lines.

Covers circuit and system level design issues of high speed communication systems, with primary focus being placed on wireless and broadband data link applications. Specific circuit topics include transmission lines, high speed and low noise amplifiers, VCO's, and high speed digital circuits.

Generally, if the frequency of the circuit reaches or exceeds 50 MHz, and the circuit working on this frequency accounts for more than 1 / 3 of the whole system, it can be called high-speed circuit. In fact, compared with the frequency of the signal itself, the harmonic frequency of the signal edge is higher, and the rapid change of the signal (rising edge or falling edge) causes unexpected results of signal transmission. Signal transmission occurs at the moment of signal state change, such as rise or fall time. The signal passes through a fixed period of time from the driver to the receiver. If the line propagation delay is greater than 1 / 2 of the rise time of the digital signal driver, the signal can be considered as a high-speed signal and produce transmission line effect. If the transmission time is less than 1 / 2 of the rise or fall time, the reflected signal from the receiver will reach the driver before the signal changes state. Otherwise, the reflected signal will reach the driver after the signal changes state. If the reflected signal is very strong, the superimposed waveform may change the logic state.