Smart bracelet, PCB layout, radio frequency circuit, clock circuit, memory circuit, sensor circuit, main
Smart bracelet PCB layout

The smart bracelet, as a relatively popular product form in the past two years, has attracted more and more people's attention. At the same time, it has also caused some changes in the electronic product market.

A smart bracelet is usually composed of a radio frequency circuit unit, a clock circuit unit, a memory circuit unit, a sensor circuit unit, and a main control MCU unit, etc., and the circuit PCB is usually concentrated in a smaller range, single-sided or double-sided SMT, the circuit board is mainly 4 or 6 layers.

Since the multi-function is concentrated on a smaller PCB board, we need to pay special attention to the layout and wiring of the bracelet. Now we summarize some precautions for reference.

PCB each part of the circuit partition layout, pay attention to wiring protection

Each part of the smart bracelet has a good partition. Because the smart bracelet is a combination of digital circuit components, as long as the matching resistance and capacitance distribution is done in the circuit design, a certain function of the circuit module can be completed, thereby making the circuit design more concise and easy to find.

About wiring, it is necessary to protect the key wiring, such as whether the clock generation circuit, crystal oscillator circuit, etc. are copper-clad protection, whether or not ground protection, etc., generally will be protected in the design, for the crystal oscillator part needs to dig copper.

Handle radio frequency circuits in PCB design

The smart bracelet needs to be linked with the mobile phone when it is used. Therefore, the radio frequency part is the key part. In this part of the design, special attention must be paid. The smart bracelets on the market are all wireless data transmission based on Bluetooth, so the focus is on the processing of Bluetooth radio frequency.

If the smart bracelet is only used for data transmission without the transmission of sound and music, then Bluetooth low energy is the best choice. During design, the shape of the Bluetooth antenna, the antenna layout, and the material of the smart bracelet shell are all important factors that affect the performance of the smart bracelet.

Do ESD protection design

Different countries and regions have different standards for different products or the same product ESD requirements. In order to make products pass related tests, ESD protection design should be carried out at the time of design. Adapt to electronic testing in the local market.

Reserved system upgrade interface

Whether the function upgrade of a smart bracelet is convenient is of great significance to users or fans of smart bracelets. If a product is upgraded at a suitable time (may be the that some functions of the early hardware design in order to catch up with the market but software has not kept up or it may be that some software bugs have been fixed), this shows that the product is still in constant development, this is a good psychological compensation for users. At present, there are usually two methods for upgrading the software of the smart bracelet: through the USB interface and the method of wireless push. As for which method to use, it needs to be determined in the preliminary planning and hardware and software planning.