4017 circuits

introduction of resistor selection experience Introduction of resistor selection experience1. Fixed resistor selection fixed resistors are available in a variety of types, the choice of which material and structure of the resistor, according to the specific requirements of the application circuit. The high-frequency circuit should choose a non-wirewound resistor with distributed inductance and small distribution capacitance, such as carbon film resistor, metal resistor and metal oxide film resis

Modern integrated op amps (op amp) and instrumentation Amplifiers (In-amp) offer a number of benefits to design engineers compared to discrete devices. Although many clever, useful and attractive circuits are provided. This is often the case because a hasty assembly of the circuit ignores some very basic problems, causing the circuit to fail to achieve its intended function-or it may not work at all. This article will discuss some of the most common a

which host to establish the connection with. Next the pad sends a X. Request to the host, creating a virtual circuit. It is pointed out that X. A virtual circuit is established, and a circuit-switched network is formed, although the data is still transmitted through a packet-switched network . If it is two X x. Communication, of course, you can call the other side directly; no pad. Theoretically, regardless of whether the X. caller and X. Definition parties are on the same transmission, it is n

SOC Technology Development The development of integrated circuits is now 40It has been following Moore's instructions and is now in the deep sub-micron stage. Due to the demand of the information market and the development of microelectronics, the feature size of the integrated circuit is constantly reduced.Small) is the main feature of the development of a variety of process integration technologies and application-oriented system-level chips. As th

This article is original by purplesword (jzj1993). For more information, see. Original web site http://blog.csdn.net/jzj1993 We have seen pictures of integrated circuits in the previous article, and there are many shapes. What really works on these chips is the transistor integrated into the silicon wafer. What we can see is that it is encapsulated with an external shell. Wire the circuit pin on the silicon wafer to the external connector to facilit

Implementation principle of TCP Segment Offload (TSO), offloadtsoIt was so hot in the morning that I suddenly remembered that someone had talked to me about TSO three weeks ago. I also described the principle of TSO. This principle is also very simple. It is nothing more than segmentation by network card hardware, calculate the checksum to free up the CPU cycle. In fact, one piece is enough. Since hardware is used for segmentation, the hardware can only calculate the checksum, because you do not

Implementation principle of TCPSegmentOffload (TSO)It was so hot in the morning that I suddenly remembered that someone had talked to me about TSO three weeks ago. I also described the principle of TSO. This principle is also very simple. It is nothing more than segmentation by network card hardware, calculate the checksum to free up the CPU cycle. In fact, one piece is enough. Since hardware is used for segmentation, the hardware can only calculate the checksum, because you do not know the segm

engineers, analog circuit is the core of engineering ideas. Engineers are not concerned about how transistors were invented, only about what the transistor has, and what kind of circuits people need in real life. Then try to use imperfect devices to create the equipment that meets the needs of people as much as possible. Using imperfect things to create perfection, engineering is doing it very often.Transistor characteristics: Learning transistors ge

Understand some hardware-related concepts in Embedded Development for embedded system development. Embedded development requires a certain understanding of digital circuits and analog circuits. In this way, in-depth research can be conducted. Next we will briefly introduce some hardware-related concepts in embedded development. ---- Level) In digital circuits, h

, the organic resistance powder is pressed in the insulator groove. Compared with the carbon film potentiometer, the organic solid potentiometer has the advantages of good heat resistance, high power, high availability and good wear resistance. However, the temperature coefficient is large, the dynamic noise is large, the moisture resistance performance is poor, the manufacturing process is complex, and the resistance accuracy is poor. It is used for voltage and current adjustment in miniaturiza

Http://forum.eepw.com.cn/thread/149216/1 What is a pull-up resistor? What is a drop-down resistor?Pulling up is to embed uncertain signals through a resistor at a high level! The resistor can throttling at the same time! The same is true for the drop-down!Pull-up refers to the injection of current to the device, and the drop-down refers to the output current. The weak strength is only the difference in the resistance of the pull-up resistor, so there is no strict distinction between them. For n

circuit:Circuit Core logic useful combination circuit implementation;?????? Asynchronous sequential circuits are the mostThe big drawback is the easy to produce burr;?????? Not conducive to device transplant;?????? Not conducive to static timing analysis (STA),Verify design timing performance. Synchronous timing Circuit:?????? The core logic of the circuit is implemented by various triggers;?????? The main signal and output signal of the circuit are

How can we improve anti-interference capability and electromagnetic compatibility when developing electronic products with processors? 1. The following systems should pay special attention to anti-electromagnetic interference:1. A system with extremely high clock frequency and extremely fast bus cycle.2. The system contains high-power and high-current drive circuits, such as relays that generate sparks and large-current switches.3. Systems with weak a

transmission, the interference of the reflected wave is easily caused by the mismatch of the Resistance. In addition, the drop-down resistance is used to effectively suppress the interference of the reflected wave. The selection principles of the pull-up resistance include: 1. Considering Power Consumption Reduction and chip current filling capacity, it should be large enough; the resistance should be large and the current should be small. 2. Make sure that the driving current is sufficient, th

rate is not high in the WAN use environment. Wan-services provided In terms of layers, the top layer of the Wan is the network layer. Services provided by the network layer for hosts connected to the network can be divided into two categories: datagram service and virtual circuit service.1. datagram Service The datagram Service (connectionless) refers to the group (that is, the datagram) sent by the host at any time by the network ). The Network selects routes for each group independently. The

demand for larger and faster processing speeds increases, the CPU seems to be less satisfactory when a task is executed. So people thought, could we put a lot of processors on the same chip and let them do things together? Will the efficiency be much higher? This is the birth of GPU. GPU was born A gpu is called a graphics processing unit. The Chinese version is a graphics processor, just like its name, GPU was initially used to run plotting operations on personal computers, workstations, game

Cables are the main cause of electromagnetic compatibility problems in the system. Therefore, in practice, it is often found that when the external drag cable on the device is removed, the device can pass the test smoothly. When electromagnetic interference occurs on the site, if you unplug the cable, the fault will disappear. This is because the cable is an efficient receiving and radiating antenna. In addition, the distance between the wires in the cable is the longest, so there is a large bra

three Bibles first, and then do the exercises.First crazy to read Razavi's "Analog CMOSIC design, and then frantically will Razavi "analog CMOS integrated circuit design" to see again, and finally crazy to finish his exercise! This is basically a bit of a concept of analog integrated circuits, looking for a few small circuitsSimulate it a bit. Adjust a op-amp try, if still no feeling, and then crazy to see a few times Razavi analog CMOS IC designHigh

reset signal is generated, the core CPU (MPC860) of the core board starts. At this time, the MPC860 starts to read the data line (D0 ~ D15), and initialize the CPU by reading the set value, including memory initialization, interrupt vector initialization, and debugging register initialization. When all hardware environments (mainly refers to all the special function registers related to the operating system in the CPU, such as SRR0, SRR1, and cr) are initialized. The system will give control to

Gpio: In the output mode of the I/O port, three output speeds (2 MHz, 10 MHz, and 50 MHz) are available ), this speed refers to the response speed of the I/O port drive circuit, rather than the output signal speed, the output signal speed is related to the Program (multiple output driving circuits with different response speeds are arranged in the output part of the chip at the I/O port, you can select a proper driver circuit as needed ). Select diffe