electronic scale

Introduction: Electronic scale, 1602 display, matrix button control, the maximum measurable weight is related to the sensor

Schematic PCB

szu simple voltmeter

Introduction: Control the output voltage value of the ad module through the stm32 chip and display it on the screen.

Schematic PCB

Sine wave 20kHz signal generator V2

Introduction: In the 12th Smart Car Competition in 2017, after I discovered that the output signal strength of the track power supply would increase as the track inductance increased, I proposed and open sourced this sine wave output track power supply. After three years of practical testing in competitions, the results are very good. The V2 version only replaces the microcontroller, and the other features remain unchanged.

Schematic PCB

2019 Question B: Rolling ball controller 1102008A

Introduction: Use openmv to perform visual analysis to identify the position of the ball and use stm32 to control the target position of the ball to achieve two-dimensional pid control of the platform, thereby controlling the movement of the ball.

Schematic PCB

Transistor tester

Introduction: Use avr microcontroller to measure components.

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LMT70 Linear Temperature Sensing Module

Introduction: LMT70 temperature sensor for easy welding

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【Electric Competition】5V Dual-way Relay

Introduction: Ordinary two-way relays are planned to be mass-produced and sold before the electric competition.

Schematic PCB

atmega328p-t12 soldering station

Introduction: atmega328p-t12 soldering station

Schematic PCB

Science and Technology Competition RC Simple Measurement of Resistor and Capacitance

Introduction: Use the NE555 RC oscillation circuit to measure the resistance, capacitance, and the square wave frequency emitted by the NE555 to meet a fixed formula. Calculate it with a microcontroller and display it on the LCD1602

Schematic PCB

PT100 AD7705

Introduction: Using AD7705 and three-wire PT100 connection, the measurable temperature accuracy is higher than 0.1℃

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[Hongshun Training Camp] Indicator light based on HK32F103RCT6

Introduction: LED indicator light for evaluating Hangshun F103 chip

Schematic PCB

Open source power meter: with power supply function, dedicated to IoT power consumption measurement

The biggest feature of testing the power consumption of IoT devices is the high dynamic range, a few uA in the sleep state and hundreds of mA in the transmitting state, and it supports dynamic switching of the measurement range. The open source power meter ZS1100A has a dynamic measurement range of 1uA to 1.5A, a resolution of 100nA, and an accuracy of 1% ± 200 nA, which is very good.

Schematic PCB

Wilo soldering pen

Introduction: Wilo RT portable soldering pen

Schematic PCB

30V3A micro electronic load (with current display)

Introduction: 30V3A electronic load with display, please pay attention to the heat dissipation of N-channel MOS

Schematic PCB

Digital tube test-light up all segments to detect whether they are good or bad

Introduction: Light up all segments to detect whether there are any problems such as missing segments on the digital tube.

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CNC electronic load-CH552

Introduction: The electronic load can reach 90W under 12V power supply (actual measurement), and supports a maximum continuous input of 36V or 3A. It uses CH552 as the main control, a rail-to-rail operational amplifier with an N-channel MOS constant current, and CH445 to control the common cathode digital tube. , 3 6*6 button operations. The radiator is 6.6 yuan from Taobao.

Schematic PCB

[Hangshun Training Camp] 485 communication display instrument-340465A

Introduction: Through the RS485 interface, Modbus-RTU protocol reads some instrument display values, 220V power supply, with a relay output and buzzer alarm.

Schematic PCB

Simple electronic load

Introduction: Simple electronic load, mainly used to test chargers, load input voltage 5-30V, maximum 5A, 100W (short time).

Schematic PCB

[Hangshun Training Camp] Current and Voltage Meter-Experimental Power Companion 47415Y

Introduction: Current and voltmeter, powered by battery, can set protection voltage and current. It is mainly used as an auxiliary device for old-fashioned experimental power supplies (the kind that adjusts voltage with a potentiometer) and is used in series with the output line of the experimental power supply.

Schematic PCB

Current and voltage meter-USB tester-V2.0

Introduction: Current and voltmeter, powered by battery, can set protection voltage and current. Can be used as a USB power test meter. The program is completely open source.

Schematic PCB