Design scheme of variable frequency speed regulation system based on DSP + IPM hardware structure

introduction Variable frequency speed regulation technology is widely used in industrial field. With the continuous development of power electronic control technology and components, the integration and intelligence of variable frequency speed regulation system are higher and higher, and the hardware composition is more and more compact and simple. DSP (digital signal processor) + IPM (intelligent […]

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Design of signal isolation self transceiver based on 74hc14 chip and adm2483 chip to realize RS-485 interface

RS-485 standard is widely used in industrial control, power communication, intelligent instrument and other fields. However, in the field environment such as industrial control, the situation is complex, and electrical noise often interferes with the transmission line; When multiple systems are interconnected, there will be potential difference between the ground of different systems, forming a […]

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Design of RS485 bus node based on magnetic coupling isolation and hardware Zero Delay Technology

introduction In many schemes of medium and long-distance communication between industrial control equipment, RS485 bus is widely used in the fields of factory automation, industrial control, community monitoring, water conservancy automatic measurement and control and so on because of its simple hardware design, convenient control and low cost. RS485 bus is driven by balanced transmitting […]

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USB bus interface circuit diagram in embedded system

A USB bus interface circuit used in embedded system is described in detail. The circuit is implemented based on USB special chip CH375, and the system hardware implementation and application program are given. The experimental results show that the circuit has the characteristics of low cost and high reliability, and can be easily integrated into […]

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Design of PS / 2 interface circuit for RFID reader

  PS / 2 interface:PS / 2 is one of the earlier interfaces used on computers. It was first developed by IBM and appeared in IBM technical reference manual. Now it is mainly used in keyboard, mouse and other devices. Most operating systems have built-in drivers that support PS / 2 interface protocol. Taking Microsoft’s 32-bit […]

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Introduction of LVDS driver based on multipoint interface

Over the years, the industry has developed a variety of mature technologies for transmitting signals on the backplane bus. With the continuous growth of Telecom and data communication services and the continuous improvement of data transmission speed, the limitations of some traditional single ended and emitter coupled logic technologies are becoming more and more obvious. […]

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Design of IC card interface circuit for single-phase smart meter

IC card interface: the circuit adopts ATMEL’s memory IC card at24c01, which is used to store the password, card number, power degree, etc. written by the power sales management system. It is a bridge between the power management department and users. In order to improve the reliability of IC card operation, there must be auxiliary […]

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Design of multi-channel can bus interface circuit based on MCP2515

At present, the mainstream can protocol controllers generally use I / O bus (SJA1000, etc.) or SPI interface (MCP2515, etc.) to communicate with MCU. Because this design uses PC / 104 bus expansion card to expand multiple RS232 and RS485 interfaces, there is no redundant I / O chip line selection available, so 9200 SPI […]

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