USB HUB based on MA8601

The schematic diagram of this chip is relatively simple and suitable for beginners to learn. In the limited space, I will briefly explain the design ideas of the entire schematic diagram.

   [LED FOR PWR]: Power indicator circuit, when the chip has input voltage, LED5 will light up, and the series resistor will limit the current. [LED FOR DOWNSTREAM PORT]: Data transmission circuit. When using different USB ports for data transmission, the current direction of the circuit is different, thus indicating the corresponding USB port. [RESET]: Reset circuit, this design does not need to be reset, so just draw it as shown in the figure. [MA8601]: The chip is powered by CON1, the input voltage is 5V, the voltage can be reduced internally to 3.3V and output through pin 13. Pin 2/3 uses a 12mhz crystal oscillator as the external crystal oscillator of the chip. The capacitor between the power supply and ground is To the filtering effect, the capacitive reactance is related to its operating frequency. In fact, there is no need to analyze the peripheral circuits of the chip in detail. Most of them involve the internal structure. Just refer to the schematic diagram. [USB]: CON1 connects to the device through a data cable, 2/3 is connected to the DP/DM pins, and is expanded into four ports, CON2, CON3, CON4, and CON5. The above is a brief analysis of the schematic diagram of the chip. I am not a professional, so please correct me if there are any mistakes or omissions.