It can be given as a gift to classmates; it's a great tool for socializing on campus.
The back has some formulas that can be replaced with other content.
The bottom is the older tin-plated version.
Programmable resistor board, flexible resistance adjustment, convenient for experiments
A tribute to
Georg Simon Ohm, the German physicist. Ohm discovered the direct proportionality between current and voltage in a resistor, the famous Ohm's Law. He also proved that the resistance of a conductor is directly proportional to its length and inversely proportional to its cross-sectional area and conductivity, and that under steady-state current, charge moves not only on the surface of the conductor but also throughout its entire cross-section. This
programmable resistor board features four interfaces on the top front for determining resistance values during DIY electronics projects. The four interfaces, with consistent functionality but different packages, cater to most scenarios. The bottom
section is the resistance programming area with eight units: 0.1, 1, 10, 100, 1kΩ, 10KΩ, 100KΩ, and 1MΩ. The total resistance output from the top interface is the sum of the values of each unit multiplied by the jumper selection factor. R = (n·0.1)+(n·1)+(n·10)+(n·100)+(n·1k)+(n·10k)+(n·100k)+(n·1MΩ) The back shows the series and parallel formulas for resistors, as well as a portrait of Georg Simon Ohm, the German physicist who discovered Ohm's Law. Testing 0 ohms (circuit error): 0.1Ω Actual resistance; 2.2Ω Actual resistance; 3.3Ω Actual resistance ; 4.4Ω Actual resistance; 5.555KΩ Actual resistance; 6.666KΩ Actual resistance; 7.777KΩ Actual resistance; 8.88MΩ Actual resistance; 9.99999999 MΩ Infinitely close to 10MΩ Actual resistance.
PDF_Programmable Resistor Board.zip
Altium_ProgrammableResistorBoard.zip
PADS_Programmable Resistor Board.zip
BOM_Programmable Resistor Board.xlsx
95648
Four-channel charger modified to turn on indicator light circuit (LM324)
The core of the circuit is the LM324 and TL431. By using voltage divider resistors, the output voltage is reduced to about 1.4V, which can charge a single rechargeable battery.
Important notes about the circuit: When using voltage divider to reduce the output voltage to about 1.4V, the adjustable resistor value should be around 2.4K. The actual measured charging voltage can reach 1.4V.
PDF_Four-channel charger converted to LED circuit (lm324).zip
Altium_Four-channel charger converted to LED circuit (lm324).zip
PADS_Four-channel charger converted to LED circuit (lm324).zip
BOM_Four-channel charger converted to LED circuit (lm324).xlsx
95649
PL5501+SW2303 100W Fast Charging
PL5501+SW2303 100W fast charging input 12V~24V
PL5501+SW2303.pdf
PL5501+SW2303-ibom.html
GerBer.zip
PL5501+SW2303.zip
PDF_PL5501+SW2303 100W Fast Charging.zip
Altium_PL5501+SW2303 100W Fast Charger.zip
PADS_PL5501+SW2303 100W Fast Charger.zip
BOM_PL5501+SW2303 100W Fast Charging.xlsx
95650
Nucleo-F411RE Development Board Upper Expansion Board
Expansion board
Nucleo Development Board Upper Layer Expansion Board Design:
This project primarily utilizes the Nucleo-F411RE development board manufactured by STMicroelectronics, leveraging its expansion interfaces for direct upper-layer integration.
This design mainly adds an OLED display module, a buzzer module, an A/D acquisition expansion module, a serial port expansion module, and a temperature sensor module to expand the functionality of the original Nucleo-F411RE development board.
PDF_Nucleo-F411RE Development Board Upper Expansion Board.zip
Altium_Nucleo-F411RE Development Board Upper Expansion Board.zip
PADS_Nucleo-F411RE Development Board Upper Expansion Board.zip
BOM_Nucleo-F411RE Development Board Upper Expansion Board.xlsx
95651
HX71708 Solution Verification Board
The HX71708 utilizes Hylink Technology's patented integrated circuit technology and is a 24-bit A/D converter chip designed specifically for high-precision electronic scales. Compared to other chips of the same type, this chip features high integration and fast response speed; simply put, it is an upgraded version of the HX711.
Selectable output data rates of 10, 20, 80, and 320Hz;
simultaneous suppression of power supply interference at 50Hz and 60Hz.
PDF_HX71708 Solution Verification Board.zip
Altium_HX71708 Solution Verification Board.zip
PADS_HX71708 Solution Verification Board.zip
BOM_HX71708 Solution Verification Board.xlsx
95652
USBHUB version 2 based on SL2.1A
The USB hub based on SL2.1A has been tested and verified.
The speed is around 35mb/s. R3 and R4 don't need soldering; they're redundant. If it's just an A to C connection, then R2 and R1 don't need soldering either. In the most basic case, you can just solder X1, U1, C9, C10, C1-C4, and USB1-USB6. The VBUs for the two Type-C interfaces are independent. If you only want to use one interface, please modify the PCB yourself; just right-click and clone. The starry sky layer is from the Bilibili user "I'm Not Surnamed Cui". [Starry Sky, PCB Replica] https://www.bilibili.com/video/BV18H4y1L7UY/?share_source=copy_web&vd_source=837b8b59718fac945ba3558f01c951c4
PDF_USBHUB Second Edition Based on SL2.1A.zip
Altium_USBHUB based on SL2.1A, version 2.zip
PADS_USBHUB based on SL2.1A, version 2.zip
BOM_USBHUB based on SL2.1A, version 2.xlsx
95653
electronic
The back has some formulas that can be replaced with other content. 
京公网安备 11010802033920号
XCS30XL-4VQ144I
