Ten Daily Electronic Common Sense-Section 47

What are the importance of the sampling theorem?

The importance of the sampling theorem is that it acts as a bridge between continuous-time and discrete-time signals.
Under certain conditions, a continuous-time signal can be completely recovered from its samples, which provides the idea of representing a continuous-time signal with a discrete-time signal. In many respects, the processing of discrete-time signals is more flexible and convenient, and thus is often preferable to processing continuous-time signals. The dramatic development of digital technology over the past few decades has produced a large number of discrete-time systems that are inexpensive, lightweight, programmable, and easy to reproduce.
The emergence of the concept of sampling and the sampling theorem makes it a reality to use discrete-time system techniques to implement continuous-time systems and process continuous-time signals. Usually, a continuous-time signal is first transformed into a discrete-time signal by sampling; then the discrete-time signal is processed by a discrete-time system; and then it is transformed back into a continuous-time system.

What is the trend of power and power management technology?

High power efficiency, low standby power consumption, high power density, high reliability, high integration and low cost are the development trends of power and power management technologies.

What is the optimization method for gate voltage scanning?

This method is mainly suitable for RRAM devices with 1T1R (one transistor one Resistors) structure.
Conventional 1T1R operation mode: Turn on the transistor connected to the RRAM by applying a fixed bias voltage at the gate terminal, select the device unit to be operated, and provide current limiting during operation.
The way of gate terminal voltage scanning: the source terminal is grounded; the drain terminal connected to the RRAM cell is placed at a fixed voltage; and the gate terminal of the transistor performs a scan mode, gradually changing the gate terminal voltage.
According to the transistor transfer characteristics, the width of the channel formed in the transistor increases as the gate bias voltage increases, and the current flowing through the channel and the memory cells connected in series increases accordingly. When the current flowing through the RRAM reaches a threshold value, the RRAM transitions from a high-impedance state to a low-impedance state.

What is a hardware timer?

Hardware timers are supported on any hardware platform. The hardware timer can trigger an interrupt after it expires according to the set counter value. For the WirelessHART standard, hardware timers must be in the microsecond range.

What is included in the LT4430?

The LT4430 contains a precision voltage reference, a wideband error amplifier, an optocoupler driver, and an overshoot control amplifier.

A simple DFD graphic description consists of the following four basic components, what are they?

1. Data flow: Describe the flow of data within the system, represented by arrows. The arrow points to the direction of data flow, and the data name is written next to the arrow.
2. Processing: Also known as data processing or data transformation, it represents the operation of data.
3. Data storage: Also known as file, it means the data that needs to be stored in the system. Data storage is the data that is in a static state within the system, while data flow is the data that is in motion within the system.
4. External objects: External objects are external things that input data to the system and receive output from the system. That is, the source and end points of the data flow are called data sources and data pools, respectively.

Which three aspects of a MOST network system are determined?

• MOST connection mechanism
• MOST system service
• MOST equipment

What is the zero drift of the strain gauge?

For the pasted strain gauges, when the temperature is constant, even if the test piece is not under stress. The indicated strain of the strain gauge also changes gradually with time, and this change is the zero drift of the strain gauge.

What are the advantages of frequency control?

The use of frequency converters for speed regulation of squirrel-cage asynchronous motors has the advantages of wide speed regulation range, good static stability, high operating efficiency, convenient use, high reliability, and significant economic benefits.

What are the verifications of serial communication data?

• Verification of serial communication data:
  1. Parity check
  2. Sum check
  3. Cyclic Redundancy Check (CRC)