The structure principle and decryption data of B-type ultrasonic diagnostic equipment

In the field of medical electronic equipment, Century Core Technology has a series of typical project results in the technical research fields of product circuit board copying, circuit board cloning, full set of product cloning, full set of technical data extraction, circuit board maintenance, equipment maintenance, etc. It can provide technical services such as circuit board PCB copying, on-board encryption chip decryption, circuit board maintenance, circuit board replacement, circuit board replication, etc. for various medical electronic equipment.

Here, we will take the B-ultrasound diagnostic system equipment as an example to analyze its structural principle and maintenance skills in detail.
1. The structural principle of the B-ultrasound diagnostic system
The B-type ultrasound diagnostic system is divided into several parts according to its structure: mainly composed of probes, transmitting and receiving circuits, analog signal processing circuits, keyboard control circuits, digital scanning converters, image display circuits, and power supply circuits.
The probe can be divided into two types according to its scanning method: linear array scanning probes and phased array scanning (fan scanning) probes. The basic principle of linear array scanning is: a number of vibrators are arranged in a linear array to form a linear array transducer, which is controlled by an electronic switch to make it time-sharing combination, work in turns, and sequentially excite from one side of the probe to the other side to generate the transmission and reception of the synthetic beam. The basic principle of phased array scanning is: the oscillators arranged in the linear array are not excited at the same time, and the excitation pulses applied to each oscillator have an equal time difference, so that the direction of the synthetic beam has a phase difference with the normal direction of the plane where the oscillators are arranged. The time difference is changed uniformly, and the phase difference is also changed uniformly. Through time control, the phased array scanning of the ultrasonic beam, that is, the sector scanning, is realized.
The B-type ultrasonic diagnostic instrument uses brightness modulation to display the reflected echoes of all interfaces in the depth direction. In the horizontal direction, by rapidly scanning, the ultrasonic echoes are emitted and received one by one, and a two-dimensional ultrasonic tomographic image of the vertical plane, that is, the line scanning tomographic image, can be obtained. If the ultrasonic beam is scanned rapidly by changing the angle, a two-dimensional ultrasonic tomographic image of the vertical fan plane, that is, the sector scanning tomographic image, is obtained. The transmitting circuit provides an excitation voltage to the probe, and realizes the scanning and focusing of the ultrasonic system beam by controlling the different arrangements and combinations of the oscillators and the excitation delay. The receiving circuit performs phase shift synthesis on the ultrasonic echo signal. The analog signal processing circuit includes a preamplifier, a TGC circuit, a dynamic filter circuit, a logarithmic amplifier circuit, and the like. The ultrasonic echo signal obtained by the image detection circuit and the Doppler detection circuit is further processed by the scan converter. The essence of the digital scan converter is a digital image processing system with an image memory. The main function is to digitize the ultrasonic signal. Then process it and finally display it on the monitor. The image processing circuit includes grayscale processing, histogram processing, data interpolation processing and other circuits. The main purpose is to improve the quality of the image.
2. Troubleshooting skills for B-type ultrasonic diagnostic system
First of all, the main reason for the failure of the B-type ultrasonic diagnostic system is the large workload of B-ultrasound and poor environmental conditions. For example, the influence of temperature, dust, power supply fluctuations and interference can increase the failure rate of the instrument. Therefore, strengthening daily maintenance work is an indispensable part of the maintenance of the B-type ultrasonic diagnostic system.
In the hands-on repair of the fault, generally speaking, swapping the color ultrasound and black and white B-ultrasound circuit boards can be used as a way to query the fault. The skills and methods that need to be paid attention to in maintenance are mainly the following aspects:
First, before carrying out specific maintenance work, as a professional engineering and technical personnel engaged in B-ultrasound maintenance work, you should first be familiar with the working principle and specific circuit structure of this type of machine, so that it is helpful to understand the various phenomena manifested by the fault from the essence of the fault. Improve the quality of maintenance.
Second, before carrying out specific maintenance, you should also first be familiar with the main functions of the instrument and various functional operations related to maintenance. In this way, from the various functions and the relationship between various functional operations, it is helpful to compress the scope of the fault, find the fault part of the instrument, and shorten the maintenance time.
Third, before carrying out maintenance, you should carefully observe and investigate various phenomena before and after the fault occurs, especially to understand the process and background of the fault in detail from the operator. B-ultrasound is a large and expensive instrument, and maintenance work is a complex project. Without fully understanding the fault situation and accurately judging the nature of the fault, you should not rashly repair it.
Fourth, the power supply part is one of the fault-prone parts in the B-ultrasound diagnostic system. Because the power supply part has large power consumption and high temperature, the failure rate is also high. The manifestations of power supply failure are also varied, often manifested as functional failure of the entire system or a part of the system. The failure of the instrument to work properly due to interference introduced by the power supply is also a kind of failure. In most cases, the power supply should be checked first to see if it is working properly.
Fifth, the peripherals in the B-ultrasound diagnostic system are also one of the parts that often fail, but the peripherals are relatively intuitive, the structure is not complicated, and each part is relatively independent, so it is relatively easy to diagnose and locate the fault. For example, the display, trackball, printer, etc., I have experienced in maintenance that the elimination of such faults is relatively simple.
Sixth, for the other components of the ultrasound diagnostic system, such as various system circuit boards, due to the high integration of the circuits and most of them are special devices, usually only board-level maintenance can be done. In the process of fault finding and diagnosis, it should be based on the circuit principle, combined with the instrument operator's description of the fault background and fault phenomenon, the fault code displayed by the instrument, the understanding and investigation of the instrument fault phenomenon, and other aspects to make a comprehensive judgment in order to determine the fault location. In the case of a B-ultrasound machine of the same or similar model, the same circuit board can be found and swapped for fault finding.