Ten Daily Electronic Common Sense-Section 24

Why does the sleep mode of TJAl020 make the power consumption of LIN ECU very low?

This is due to the very low current consumption of the transceiver itself and the shutdown of the external voltage regulator through the INH output. Therefore, in sleep mode, the INH pin is left floating.

Why is the power supply design for point-of-load (POL) processors for digital TVs, cable modems, and set-top boxes becoming more challenging?

Power supply designs for point-of-load (POL) processors for digital televisions, cable modems, and set-top boxes are becoming more challenging due to higher integration, faster processor speeds, and lower price targets.

What is the development trend of development tools?

1. It has mixed-signal processing capabilities: Due to the different characteristics of digital circuits and analog circuits, the development of analog integrated circuit EDA tools is far behind that of digital circuit EDA development tools.
2. Efficient simulation tools: In the entire electronic system design process, simulation is the work that takes the most time, and it is also a link that takes the most time for EAD tools.
3. Ideal logic synthesis and optimization tool: The logic synthesis function is to automatically translate the high-level system behavior design into the circuit description of gate-level logic, achieving the independence of practice and technology.

What are the SPI interface features?

• The SPI interface features are as follows:
  1. It has 2 completely independent SPI controllers;
  2. Follows the Synchronous Serial Interface (SPI) specification;
  3. Full-duplex data communication;
  4. Can be configured as SPI master or slave;
  5. The maximum data bit rate is 1/8 of the peripheral clock FPCLK.

Information system development methodology is a branch of discipline that studies the law of information system development. What is the main content of its research?

1. Analyze and summarize past experience at a higher level, study the general laws of information system development, and establish the basic principles of the guiding ideology of system development with general significance.
2. From the perspective of systems engineering, provide analysts with a coordinated local and overall Interested thinking methods, as well as specific analysis and design principles.
3. Establish corresponding implementation steps around the established various development methods and principles of guiding ideology.
4. Research N-‘a complete set of description and development tools corresponding to the system development idea and suitable for each implementation step.
5. Organization and implementation methods in the development of information systems.
6. The key factors and necessary conditions for the success of the system development, as well as the organizational operation mechanism that promotes the success of the system development.

What can an electromagnetic flow meter (EFM) do?

An electromagnetic flow meter (EFM) continuously measures the instantaneous or average flow rate of blood and converts the flow rate.

What is the working principle of the contact logic encryption card?

The semiconductor chip in the card is directly in contact with the external interface device through a tangible metal electrode diaphragm (contact) to provide power for the chip to work and exchange data.

Ohmic resistance function：

• It has the following functions:
  1. Use it as a jumper. This is both beautiful and easy to install.
  2. In mixed circuits such as digital and analog, two grounds are often required to be separated and connected at a single point. Instead of connecting these two grounds directly, we can use a 0 ohm resistor to connect these two grounds. The advantage of this is that the ground wire is divided into two networks, which is much more convenient when processing large areas of copper. Incidentally, in such cases, inductance or magnetic beads are sometimes used to connect.
  3. Use as a fuse. Due to the large fusing current of the traces on the PCB, it is difficult to fusing when a fault such as short circuit and overcurrent occurs, which may bring about a greater accident. Since the 0 ohm resistor has a relatively weak current bearing capacity (in fact, the 0 ohm resistor also has a certain resistance, but it is only small), the 0 ohm resistor will be blown first when there is an overcurrent, thereby disconnecting the circuit and preventing a larger accident happened. Sometimes a small resistor with a resistance value of a few tenths or a few ohms is used as a fuse. However, it is not recommended to use it in this way, but some manufacturers use it in order to save costs.
  4. The position reserved for debugging. You can decide whether to install it, or other values ​​as needed. Sometimes it is also marked with *, indicating that it is determined by debugging.
  5. Used as a configuration circuit. This function is similar to a jumper or a DIP switch, but it is fixed by welding, which prevents ordinary users from modifying the configuration at will. By installing resistors in different locations, you can change the function of the circuit or set the address.

What kinds of filtering are commonly used in digital filtering algorithms?

Commonly used digital filtering algorithms include program judgment, median value filtering, arithmetic mean filtering, recursive average filtering, weighted recursive average filtering, first-order inertial filtering, and composite filtering.

What is the readout display part of the digital oscilloscope?

The readout display portion is composed of a display buffer memory, a D/A converter, a scan generator, an X amplifier, a Y amplifier, and an oscilloscope circuit.