Ten Daily Electronic Common Sense-Section 19

What is the purpose of active PFC technology?

The purpose of active PFC technology is to improve the input power factor of the switching power supply and reduce the input current harmonics to meet the IEC1000-3-2 standard.

What are the ways to integrate a module into a black box in Synplify Pro?

There are two ways to integrate a module into a black box in Synplify Pro. One is to simply make the module name and port declaration for the module. If the function entity is empty, Synplify Pro automatically combines it into a black box: secondOne way is to use a comprehensive constraint.

What is an analog switch?

Analog switches are commonly used in analog Integrated Circuits(ICs)s and are widely used in switched capacitor circuits and sampling circuits.Since the analog signal is processed, the analog switch is required to have a small on-resistance, a large off resistance, and sufficient transmission accuracy.

What methods can be used to prevent aliasing at the sampling rate?

There are a few simple ways to prevent aliasing from occurring:
Adjust the sweep speed;
Use Autoset: Try switching the collection mode to envelope mode or peak detection mode.
Because the envelope method looks for extreme values in multiple collection records, and the peak detection method looks for the maximum and minimum values in a single collection record. Both methods can detect faster signal changes.
If the oscilloscope has the Insta Vu acquisition mode, it can be selected. Because of the high speed of acquiring waveforms in this way, the waveforms displayed in this way are similar to those displayed on an analog oscilloscope.

What is the method of identifying the resistance value?

The resistance value representation method of exclusion is the same as the 3-digit representation and 4-digit representation in resistors, for example, as follows. (1) For example, if an exclusion is marked as l00, the resistance value is 10f2; 473 is 47kQ. The 3-digit exclusion is the E24 series. (2) For example, if an exclusion is marked as l202, the resistance value is 12k. Q; The resistance value of 1542 is l5.4k. Q. The exclusion indicated by 4 digits is the E96 series. (3) If there is a decimal point in the resistance value, it is represented by “R”, and it occupies one significant figure. For example, if an exclusion is marked as 22R1, the resistance value is 22.1f2. (4) If an exclusion is marked as “0” or “000”, its resistance value is 0f2, and this exclusion is actually a jumper (short-circuit).

What methods can control the forward current of the LED?

1. The U-I curve of the LED is used to determine the voltage that is required to be applied to the LED to produce the expected forward current.
2. The preferred LED current adjustment method is to use a constant current power supply to drive the LED.

What types of data can be classified based on the source of the data generation?

Divided into two categories: predefined types and user white definition types.

What are the advantages of intelligent power modules?

1. The switching speed is fast, the driving current is small, and the control and driving are simpler.
2. It contains a current sensor, which can detect overcurrent and short-circuit current efficiently and quickly, and can give sufficient protection to the power chip, and the failure rate is greatly reduced.
3. Due to the optimization of the wiring design of the power supply circuit and the drive circuit inside the device, the problems caused by surge voltage, gate oscillation, and noise can be effectively controlled.
4. There are abundant protection functions, such as current protection, voltage protection, and temperature protection. With the advancement of technology, the protection function will be further improved.
5. Due to factors such as the reduction of switching power supply capacity, drive capacity, device saving and overall performance improvement after using IPM, the cost performance of IPM has been higher than that of IGBT, and the price of IPM has gradually approached that of IGBT, with good economy.

What are the problems with 3G mobile phone power?

1. Industrial design considerations allow mobile phones to be designed in a variety of ways depending on the required functionality and ergonomics. Today, there is a need to consider whether mobile phones can be designed in the shape of lumps, clam shells, or slides, all with different display, keyboard, and speaker configurations. These design differences have a large impact on the placement of mobile phone displays, camera modules, and other subsystems, and can limit the integration of these devices to some extent. In some cases, the “all-in-one” integration of power or audio functions can mean longer traces, complex PCB layouts, or design challenges due to noise.
2. One should also not forget the cost-effective management of mobile phone model series required by mobile phone manufacturers. In order to meet market demand with different mobile phone models, mobile phone manufacturers must offer various features and performance levels at different costs. To maximize profits in a competitive market, the cost of these models must vary by function, which in turn limits the integration of each function onto a large IC. If features are not required for a given model series, some specific features and their power supplies should be removed from the board f: to reduce cost.
3. Mobile phone manufacturers using the same basic chipset also need to differentiate their products from those of other competitors, which in turn drives re-integration of various features. A typical example of product differentiation might include (but is not limited to) brighter camera flash, more powerful blowtorch mode, Class D stereo audio performance, special display and keyboard backlighting, MP3 audio playback capability, FM radio reception With accurate battery capacity metering, etc.

Which requests does MSCAN allow in the following ways?

1. Set the corresponding abort confirmation flag (ABTAK) in the CANTAAK register.
2. Set the relevant TXE flag to release the buffer.
3. Generate a transmission interrupt.