Domestic LVDT Signal Conditioning Circuit - HJG598

Release time:

2021-09-30

With the increasing uncertainty in the international environment and the continuous escalation of Sino-U.S. frictions, the suppression of China's integrated circuit industry by the U.S. and others is gradually expanding. It is becoming increasingly difficult to procure imported integrated circuits, with prices soaring hundreds or thousands of times, severely impacting China's economic development and national security. The trend towards domestic production in the integrated circuit industry is inevitable. In light of the country's increased policy support for the integrated circuit industry, which aims to gradually achieve domestic substitution of the integrated circuit supply chain, our company has launched a self-produced LVDT signal conditioning circuit, HJG598, based on over 200 types of domestically produced integrated circuits after preliminary market research, program validation, experimental verification, and our own technological accumulation and research. This product can functionally replace the imported AD598. Overview HJG598 is an LVDT signal conditioning circuit designed using thick film integration technology. It includes a positive sine wave oscillator and power driver to generate an excitation signal for driving the primary side of the LVDT. At the same time, HJG598 conditions and converts the amplitude-modulated (AM) signal output from a rotary transformer into a DC voltage, providing adjustable sum output (A+B) and difference output (A-B). Unlike AD598, it does not perform ratio division internally on-chip, making it easier for customers to directly determine whether the electrical connection between excitation and rotation is normal based on sum output (A+B). Users can implement division calculations on DSPs or microcontrollers with arithmetic functions to quantify angles. The HJG598 LVDT signal conditioning circuit is very suitable for precision industrial position and measurement applications due to its low temperature drift, high detection accuracy, high reliability, and high sensitivity. It is widely used in angle position detection systems in fields such as servo control systems, aerospace, electronics, etc. In summary, HJG598 truly realizes domestic substitution for AD598. Electrical Schematic Package Form and Pin Functionality 1. Package Form It uses ceramic dual in-line package HD14-02B and HD14-02C ceramic surface mount leadless packages; dimensions are shown in Figure 2: 2. Pin Functionality Table 2 shows pin functionality for packaging. Electrical Characteristics Unless otherwise specified: VCC=+15V,VEE=-15V,T_A=25℃. Typical Application Diagram Note: 1. Changing RSCL can alter EXC's amplitude; 2. Capacitors CT1 and CT2 must be paired and should use NPO/COG dielectric capacitors; 3. The REF pin can adjust the zero point of output voltage VA-B.