Filter circuit (various design solutions + schematic diagram).rar

Filter circuit (various design solutions + schematic diagram)

Schematic PCB

51 microcontroller control example of RTL8019 Ethernet (original program + schematic diagram)

51 microcontroller to RTL8019 Ethernet control example (original program + schematic diagram).

Schematic PCB

UDP test based on STM32 and network chip W5200

UDP test based on STM32 and network chip W5200

Schematic PCB

Network card driver and LWIP protocol transplantation program source code for Ethernet communication module based on LPC2138 and DM9000AE

The network card driver and LWIP protocol transplant program source code for the Ethernet communication module based on LPC2138 and DM9000AE written by myself.

Schematic PCB

Broadband amplifier based on 51 microcontroller

This design uses the variable gain wideband amplifier VCA810 to increase the gain and expand the AGC control range, and uses software compensation to reduce the step interval of the gain adjustment and improve the accuracy. The input part uses a high-speed voltage feedback op amp 0 P A842 as a follower to increase the input impedance, and a protection circuit is added to the input part without affecting performance. Various anti-interference measures are used to reduce noise and suppress high-frequency self-excitation. The power output part is made of discrete components. The passband of the entire system is 4.4 k Hz ~ 8.4 MH z, with a minimum gain of 0 dB and a maximum gain of 70 dB. The gain step is ld B/6dB/arbitrarily set. The error between the preset gain and the actual gain below 60 dB is less than 0.2 dB. The effective value of the undistorted output voltage reaches 10.1 V, and the AGC control range is 52 dB when outputting 4.5 ~ 5.5 V.

Schematic PCB

Remote control ultrasonic ranging smart car based on arduino

The design uses an Arduino microcontroller as the main control chip to achieve distance measurement and display, and can intelligently avoid obstacles. The operating status of the car can be controlled through the remote control. Its structure is simple, easy to implement, the overall design is reasonable, the work is stable, the performance is good, and the detection Fast speed and easy to achieve real-time control are the design concepts of mainstream intelligent information fusion technology. It has powerful functions, modular design, strong portability, low power, and has a wide range of application fields and development prospects.

Schematic PCB

Gigabit Ethernet PHY and PC point-to-point communication procedures and corresponding tests

The physical layer data sending and receiving of a PC is very simple. As long as one condition is met, that is, the CRC check of the data packet is correct, the network card can send the data packet to the application software. Otherwise, the network card will directly discard the data packet, which cannot be caught by any software. to the data packet.

Schematic PCB