(Study Diary) 2023.5.9

Written in front:
Due to the lack of time and the fragmentation of learning, blogging has become a bit of a luxury.
But the desire to record learning (forgetting to be able to quickly review it later) grows stronger by the day.
In this case
, it is better to take the day as the unit and the time as the order, just use the blog as a catalog of knowledge learning, record the most popular and helpful information that the author thinks, and try to summarize a few sentences to indicate the essence, so that it will be easier to search in the future easy.


The structure of the title is as follows: "Type": "Knowledge Points" - "Short Explanation"
part of the content cannot be uploaded due to non-disclosure agreement.


点击此处进入学习日记的总目录

1. Signal: AI, AO, DI, DO, PI, PO

1. In the control system, what do , , , , mean? In the control system, , , are AIcommon AObasic DIlabels DOon the modules in PIthe distributed control system. The advantage is that it is easy to distinguish what type of card is, and it is also convenient for later maintenance and maintenance . In fact, it is to clearly classify the on-site analog meters and switching devices, etc., to facilitate the weak current signal wiring of the instruments and devices in the later stage. , , , they are the acronyms of the English names, the full English name of (analog quantity), the full English name of (digital quantity), the full English name of (input), and the full English name of (output). Therefore, it means analog input, analog output, digital input, and digital output. There are many cards in the control cabinet in the distributed control system, and the above-mentioned types of cards will be used to define which type of card it is.PO
AIAODIDO
AIAODIDOAAnalogDDigitalIInputOOutputAIAODIDO
   

2. AIAnalog quantity input card
   Function: convert the analog quantity of the controlled object into a digital signal that the computer can recognize. The analog quantities of the controlled object include: temperature, pressure, flow, liquid level, and composition. There are also thermocouple and thermal resistance input cards. These cards are collectively referred to as AI input modules or AI input devices.
   

3. AOAnalog output card
   Function: Convert the output digital signal of the computer into an analog signal that can be accepted by external process control instruments or devices. Purpose: It is to drive the control of various actuators on site. For example, the control of electric control valves and pneumatic control valves on site.
   

4. DIDigital input card
   Function: Convert the switch signal with only two states in the production process into a signal form that can be recognized by the computer. For example, on-site limit switches, relays, motors and other digital status.

5. DODigital output card
   Function: convert the digital signal expressed by the binary code output by the computer into a digital signal that can control the production process or display the state. For example, on/off of the on-site indicator light, on/off of the motor, on/off of the valve, on/off of the relay and other state control and state display of the switch quantity.
   The distributed control system is to realize the centralized management and decentralized control of the entire production process. The variable signals reflecting the production process are sent to the control room, and the control variables are sent to the site at the same time, which is conducive to safe production and economical operation in the production process.
   
   

6. PI/ POpulse input/output
   

Link:
Summary of the principle, classification and conversion of instrument signals such as AI/AO/DI/DO/PI/PO!
What is analog quantity, AI and AO explanation

2. Device: EC20-MINIPCIE——SIM card communication

1. EC20-MINIPCIEIt is a modular mobile communication solution based on PCIe( ) interface. It is a wireless communication module produced Peripheral Component Interconnect Expressby China's Wireless Communication Co., Ltd., which can be used to connect to mobile networks (such as , , and ) for data transmission and communication. A card that can be embedded in a computer or other device to enable it to communicate wirelessly over a mobile network. It supports a variety of network frequency bands and technologies, including , , , , and etc., and provides worldwide network coverage. Some other functions are also available, such as GNSS ( ) positioning and Bluetooth communication. It can be used in various application scenarios, such as smart transportation, smart grid, smart security, smart medical care, Internet of Things ( ), etc.Quectel2G3G4G5G
EC20-MINIPCIEMini PCIeLTE-FDDLTE-TDDWCDMATD-SCDMAGSMCDMA2000
EC20-MINIPCIEGNSSIoT

2. pin name
   

3. pin function
   

Detailed content:
Detailed explanation of the hardware circuit of the miniPCIE network module EC20

3. Device: LDO - power management chip

1. In a circuit board, we will use a variety of voltages. Generally, there are three ways for us to obtain these voltages. One is introduced from the outside for processing; the other 滤波隔离is the internal conversion of the circuit board. The internal conversion is nothing more than using 电源芯片管理芯片to convert the required voltage.
   Generally, the power management chip we use is nothing more LDOthanDC-DC
2. LDO=low dropout regulator, 低压差++ . 线性_ " ": The output voltage drop is relatively low, such as input V, the output can reach V. " ": The internal tube works as a linear resistor. " " indicates that the purpose is to stabilize the power supply. Since the general package is much smaller and the cost is much lower, so in many factories, we will use it to convert the voltage we need. Of course , under the premise of choosing to use it, it is necessary to meet the noise requirements Basic requirements such as response and power consumption. One piece only costs about 50 cents, while one piece costs 5 yuan. It can be seen that the cost is much lower.稳压器
低压差3.33.2
线性LDOMOS
稳压器LDO
LDODC-DCLDOLDO
spx1117m3-3.3TPS5430LDO
   
3. As can be seen from the figure above, LDOthe use and model characteristics of the chip;
   the general LDOchip has one input, one output, one enable, and one ground, unlike DC-DCthe power supply chip, which also needs to obtain the output voltage through the external resistor.
   The model naming feature is included in the chip model, 输出电压so it is much more convenient when selecting a model.
   The above two points are also an important basis for distinguishing whether the power chip is DC-DC or DC LDO.

Details:
What is LDO (low dropout regulator)