A rectangular wave generator can be made by using the 2MHz passive quartz crystal of the AVR microcontroller and the 6-phase inverter 74HC04, plus a few 1/4W color ring resistors. The following figure shows the pin distribution of 74HC04.
As shown in the figure above and below, the 14th pin of 74HC04 is the power pin, connected to the positive 5V DC power supply, and the 7th pin is connected to the negative pole of the 5V DC power supply. In this design, the first three inverters of 74HC04 are used to form a rectangular wave generator.
The figure below is the schematic diagram of the unlocker circuit.
In the figure below, the first inverter input and output of the 74HC04 labeled U1A is connected in parallel with a 1MQ 1/4W resistor and a 2M 2-pin quartz crystal. Two 22pF ceramic capacitors C1 and C2 are used to fine-tune the frequency of the quartz crystal. U1C is the output inverter. In order to ensure that the waveform is relatively complete, a 2K ohm pull-up resistor is connected to the output.
If the AVR microcontroller is locked by itself, just connect the circuit to a 5V DC power supply, and then connect the other end of the wire from J1 to the XTAL1 pin of the AVR microcontroller, and directly re-download the program through the ISP port of the AVR microcontroller, and re-write the correct fuse position to unlock the AVR microcontroller.
Depending on the different types of AVR chips allowed, the clock range can be selected from 1MHz to 16MHz.
Previous article：Microcontroller entry design: a simple and fun heart rate meter
Next article：Typical case development of single chip microcomputer (II)
Recommended ReadingLatest update time:2024-11-16 19:44
MCU C language tutorial: Building your first KeilC51 project
With the continuous development of single-chip microcomputer technology, high-level languages with single-chip microcomputer C language as the mainstream are also constantly loved by more single-chip microcomputer enthusiasts and engineers. When using C51, you must use a compiler to compile the written C program i
[Microcontroller]
Using BootLoader to Upgrade Online in PIC18 Microcontroller
Introduction
The BootLoader of PIC microcontroller is the kind that needs to be written by yourself. You can write BootLoader programs with various functions according to your needs. At present, the more common BootLoader programs are Microchip's C18 version and the PICC18 version of the famous PICC compile
[Microcontroller]
MSP430 MCU controls IO port operation - LED flashes
//******************************************************************************* // D13x Demo - Change the system clock based on the previous section and observe the blinking frequency of the LED light // // Description: Change the blinking frequency by changing the system clock; invert P1.5 through P1 XOR; software
[Microcontroller]
Xinchi Technology E3 high-performance MCU is officially mass-produced and shipped
Recently, Xinchi Technology's first batch of high-performance MCU "Control Core" E3 was officially delivered to customers, which means that Xinchi Technology MCU has entered the era of mass production and can provide the industry with a series of high-performance, high-functional safety automotive-grade MCU chip produ
[Automotive Electronics]
The "Soul" of the Microcontroller - The Use of Data Memory
We can say that the program memory stores the soul of the microcontroller, which is the working program. The smallest one may be only 1KB (it can only hold 1024 8-bit data at most, because there are many 2-byte and 3-byte instructions in the actual instructions, so it cannot hold 1024 instructions) and the largest o
[Microcontroller]
Single chip campus bell system source program
Main frequency 12M Function: 1. Use DS1302 to obtain clock signal and set time. 2. Can set 10 groups of bell time and has temporary bell function. The bell duration is 5S. 3. 1602 LCD screen displays data. The simulation schematic diagram is as follows . Usage: Press "÷" to adjust the time, press the adjustmen
[Microcontroller]
Monitoring system of cleaning test bench based on single chip microcomputer control
In recent years, with the continuous development of my country's economy and the continuous improvement of people's living standards, people have higher and higher requirements for the quality of life. Therefore, the requirements for the working performance of grain cleaning machinery in grain cleaning operations
[Microcontroller]
- Popular Resources
- Popular amplifiers
-
Wireless Sensor Network Technology and Applications (Edited by Mou Si, Yin Hong, and Su Xing) - Modern Electronic Technology Training Course (Edited by Yao Youfeng)
- Modern arc welding power supply and its control
- Small AC Servo Motor Control Circuit Design (by Masaru Ishijima; translated by Xue Liang and Zhu Jianjun, by Masaru Ishijima, Xue Liang, and Zhu Jianjun)
Wireless Sensor Network Technology and Applications (Edited by Mou Si, Yin Hong, and Su Xing)
Recommended Content
Latest Analog Electronics Articles
- High signal-to-noise ratio MEMS microphone drives artificial intelligence interactionAuthor: Dr. Gunar Lorenz Senior Director of Technology Marketing, Infineon Technologies Proofreader: Ding Yue Chief Engineer, Greater China, Consumer, Computing and Communications Business, Infineon Technologies Introduction At Infineon, I ...
- Advantages of using a differential-to-single-ended RF amplifier in a transmit signal chain designTraditional radio frequency (RF) transmit signal chains typically use a digital-to-analog converter (DAC) to generate a baseband signal. This signal is then up-converted to the desired RF frequency using an RF mixer and a local oscillator. ...
- ON Semiconductor CEO Appears at Munich Electronica Show and Launches Treo PlatformDuring Electronica, ON Semiconductor CEO Hassane El-Khoury was interviewed by Power Electronics News at the exhibition site and gave a detailed introduction to the new products that ON Semiconductor brought to the market. ...
- ON Semiconductor Launches Industry-Leading Analog and Mixed-Signal PlatformThe Treo platform uses a modular architecture that accelerates the development of intelligent power management, sensor interface and communication solutions. The Treo platform is based on 65-nanometer BCD process technology and supports ...
- Analog Devices ADAQ7767-1 μModule DAQ Solution for Rapid Development of Precision Data Acquisition Systems Now Available at MouserMouser Now Stocking Analog Devices ADAQ7767-1 μModule DAQ Solution for Rapid Development of Precision Data Acquisition Systems November 6, 2024 – Offering a broad range of semiconductor and electronics ...
- Domestic high-precision, high-speed ADC chips are on the rise
- Microcontrollers that combine Hi-Fi, intelligence and USB multi-channel features – ushering in a new era of digital audio
- Using capacitive PGA, Naxin Micro launches high-precision multi-channel 24/16-bit Δ-Σ ADC
- Fully Differential Amplifier Provides High Voltage, Low Noise Signals for Precision Data Acquisition Signal Chain
MoreSelected Circuit Diagrams
MorePopular Articles
- Innolux's intelligent steer-by-wire solution makes cars smarter and safer
- 8051 MCU - Parity Check
- How to efficiently balance the sensitivity of tactile sensing interfaces
- What should I do if the servo motor shakes? What causes the servo motor to shake quickly?
- 【Brushless Motor】Analysis of three-phase BLDC motor and sharing of two popular development boards
- Midea Industrial Technology's subsidiaries Clou Electronics and Hekang New Energy jointly appeared at the Munich Battery Energy Storage Exhibition and Solar Energy Exhibition
- Guoxin Sichen | Application of ferroelectric memory PB85RS2MC in power battery management, with a capacity of 2M
- Analysis of common faults of frequency converter
- In a head-on competition with Qualcomm, what kind of cockpit products has Intel come up with?
- Dalian Rongke's all-vanadium liquid flow battery energy storage equipment industrialization project has entered the sprint stage before production
MoreDaily News
- Allegro MicroSystems Introduces Advanced Magnetic and Inductive Position Sensing Solutions at Electronica 2024
- Car key in the left hand, liveness detection radar in the right hand, UWB is imperative for cars!
- After a decade of rapid development, domestic CIS has entered the market
- Aegis Dagger Battery + Thor EM-i Super Hybrid, Geely New Energy has thrown out two "king bombs"
- A brief discussion on functional safety - fault, error, and failure
- In the smart car 2.0 cycle, these core industry chains are facing major opportunities!
- The United States and Japan are developing new batteries. CATL faces challenges? How should China's new energy battery industry respond?
- Murata launches high-precision 6-axis inertial sensor for automobiles
- Ford patents pre-charge alarm to help save costs and respond to emergencies
- New real-time microcontroller system from Texas Instruments enables smarter processing in automotive and industrial applications
Guess you like
- Does the material of the transformer determine the operating frequency of the transformer?
- CV2880 simple datasheet
- Washing machine problems
- Problem with STM32F767 serial port 7
- Characteristics of DC Power Supply
- How to choose between JTAG protocol and SWD protocol for MCU programming and debugging?
- Learning Dynamics—Case Study Results Demonstration Sine Wave and Triangular Wave Signal Generator Design
- [MM32 eMiniBoard Review] ADC collects potentiometer data and sends it to the computer for display via USB-CDC
- Has anyone made a circuit that triggers a low level for 2ms and then maintains the low level for 80ms?
- Device selection - What parameters should be paid attention to when selecting TVS tubes?
京公网安备 11010802033920号