This electronic perpetual calendar, built with a 51 microcontroller and a 03T voice module, is highly practical. A demonstration video can be found here: https://v.douyin.com/iBuELeMQ/ (
For those interested in learning more, please download the program: Digital Tube Electronic Perpetual Calendar 20241101 Program Upgrade and Optimization.zip). It can display the lunar calendar years 2000-2099. Kudos to the engineer who invented this lunar calendar algorithm!
The calendar uses an STC8H1K17 microcontroller and a TM1640 chip to drive a multi-digit digital tube electronic perpetual calendar. It features eight brightness levels in manual mode and a light sensor in automatic mode. The timing uses a high-precision DS3231 clock chip. The circuit is simple yet powerful, displaying the lunar calendar, day of the week, and providing accurate timekeeping.
Digital Tube Perpetual Calendar.zip
jx_firm.tar.gz
Gerber_10cmx20cm Full Version (No Window)_2024-09-29.zip
Electronic clock finished product display.mp4
Digital Tube Electronic Perpetual Calendar 20241101 Program Upgrade and Optimization.zip
PDF_Digital Tube Electronic Perpetual Calendar (with Lunar Calendar Display + Dot Matrix Screen for Day of the Week).zip
Altium Digital Tube Perpetual Calendar (with Lunar Calendar Display + Dot Matrix Screen for Day of the Week).zip
PADS Digital Tube Perpetual Calendar (with Lunar Calendar Display + Dot Matrix Screen for Day of the Week).zip
BOM_Digital Tube Electronic Perpetual Calendar (with Lunar Calendar Display + Dot Matrix Screen for Day of the Week).xlsx
91814
Battery charging module 2-cell - TX5817
This project is a 2-cell lithium battery charging management module with a built-in TX5817 chip and a maximum charging current of 1.5A.
This module
is a wide-voltage input charging management chip specifically designed for dual-cell lithium batteries, compatible with 5V and 9V adapters.
With 5V power supply, it achieves boost charging with a maximum battery charging current of 1.5A.
With 9V power supply, it achieves buck charging with a maximum battery charging current of 1A.
The charging current can be set via an external resistor RSET.
Project Parameters
: • Built-in OVP
• High input voltage up to 26V, excellent surge protection
• Automatic recognition of 5V or 9V charger input
• Adaptive input current function
• Minimal external components, supports 2.2μH inductor
• Battery charging current up to 1.5A
• Adjustable charging constant current
• Trickle, constant current, and constant voltage charging modes
• Charging status indication
• NTC battery high and low temperature protection
• Frequency dithering design for ultra-low EMI
• Built-in undervoltage and overtemperature protection
• Lead-free and halogen-free package, ESOP8
Application Areas:
• Bluetooth speakers
• Walkie-talkies
• Smart home
• Power tools
Principle Analysis (Hardware Description) Charging Current
Design Formula: To prevent damage to the chip from transient high voltage during hot-plugging of the charging head, two 22μF capacitors need to be added near the charging interface. Additionally, add a 1μF capacitor near the VIN pin of the TX5817 chip to filter out high-frequency noise. For the VSYS pin, choose a 22μF ceramic chip capacitor and place it as close as possible to the negative end of the Schottky diode. Also, choose a 0.1μF capacitor and place it as close as possible to the VSYS pin. The indicator light status NTC circuit has built-in over-temperature protection, or an external NTC circuit can be used. The calculation formula is as follows: The above diagram shows the application circuit and calculation method for the NTC pin temperature detection of the TX5817. The resistance values of a 10K NTC resistor with a B value of 3950 at the preset high and low temperature protection points are (e.g., at -5℃, RNTC=41.306kΩ, at 50℃, RNTC'=3.588kΩ). Precautions .
TX5817 Product Manual V1.1.pdf
PDF_Battery Charging Module 2-Series - TX5817.zip
Altium Battery Charging Module 2-in-1 - TX5817.zip
PADS_Battery Charging Module 2-Serial-TX5817.zip
BOM_Battery charging module 2-cell-TX5817.xlsx
91816
air001 (PY32F002A) Minimum System Board
Simple AIR001 minimum system board
The AIR001 (PY32F002A case) minimum system board has been verified to work well. However, please use a pull-down resistor of no more than 2K ohms for PB6; otherwise, startup may sometimes be abnormal.
Project Introduction: This is a minimum system board with all AIR001 pins exposed, featuring an LDO, crystal oscillator, and reset button, optimized for small wiring area.
Related Functions: All functions supported by AIR001 can be implemented; its main advantage is its low price.
PDF_air001 (PY32F002A) Minimum System Board.zip
Altium_air001 (PY32F002A) Minimum System Board.zip
PADS_air001 (PY32F002A) Minimum System Board.zip
BOM_air001 (PY32F002A) Minimum System Board.xlsx
91817
Lithium Battery Management 2-3 Serial-TX5818 Functional Test Board
Lithium battery management 2-3 SATA - TX5818 functional test board, maximum charging current is 1.55A.
Project Overview:
This project is a charging management module with a wide input voltage range, capable of charging dual-cell and triple-cell lithium batteries in series. In
dual-cell lithium battery mode, it is compatible with 5V and 9V adapters.
With a 5V supply, it provides boost charging for both dual-cell and triple-cell lithium batteries. With a 9V supply, it provides linear buck charging for dual-cell lithium batteries. The charging current can be set via an external resistor RSET.
Project Features
: Built-in OVP
26V input withstand voltage, excellent surge protection
Automatically identifies whether the connected charger is 5V or 9V in dual-cell lithium battery mode
Supports adapter current adaptive function
Minimal external components, supports 2.2μH inductor
15mA battery full charge cut-off current
±1% battery full charge voltage accuracy
Maximum battery charging current up to 1.55A
Charging efficiency up to 88%
Adjustable charging constant current value
Trickle, constant current, and constant voltage charging modes
Charging status indication
NTC battery high and low temperature protection
Frequency dithering design for ultra-low EMI
Built-in undervoltage protection and overtemperature protection
Lead-free and halogen-free package, QFN3×3-16
Project Parameters
: VIN: 5/9V, VOUT: 2-3 series, Imax: 1.55A
Built-in: TX5818
Principle Analysis (Hardware Description)
Charging Current Setting
Indicator Status
Output Battery Quantity Setting
Charging Cell Selection Pin is 11. The CELL pin is left floating or connected to a 10kΩ resistor to ground for dual-cell charging mode. Connecting a 10kΩ resistor to the LDO enables triple-cell charging mode.
Single Cell Rated Voltage Setting
Battery Full Charge Voltage Selection Pin is 6. The FV_SEL pin is left floating or connected to a 10kΩ resistor to ground. Dual-cell full charge voltage is 8.4V, triple-cell full charge voltage is 12.6V. Connecting a 10kΩ resistor to the LDO enables dual-cell full charge voltage of 8.7V, triple-cell full charge voltage of 13.05V.
Battery Temperature Monitoring
To prevent damage to the battery from excessively high or low temperatures, the TX5818 integrates a battery temperature monitoring circuit. Battery temperature monitoring is achieved by monitoring the voltage at the NTC pin. The NTC pin voltage is determined by the NTC thermistor inside the battery and a resistor divider network, as shown in a typical application circuit.
If battery temperature monitoring is not required, the NTC pin can be left floating. After one charging cycle, the TX5818 will turn off the charging display. During this period, the battery may experience a decrease in charge due to natural discharge.
To prevent the battery from automatically depleting while connected to the adapter, a new charging cycle will automatically begin when the battery voltage drops to the automatic charging threshold (typically 8.2V for dual-cell lithium batteries and 12.3V for triple-cell lithium batteries). LAYOUT Notes: 1. The current from VIN through the inductor and diode to pin 1 (VSYS) of the chip carries a large current. The traces in this loop should be as thick and short as possible, and the inductor and diode should be placed close to the chip. 2. A 0.1μF and a 22μF surface-mount capacitor must be placed at the boost output pin (VSYS). The 22μF capacitor should be placed with one end close to the VSYS pin and the other end close to the chip's ground (pins 4/5) (see screenshot). A 1206 package is recommended for the 22μF capacitor. 3. A 1μF and two 22μF surface-mount capacitors need to be placed at the VIN terminal. These three capacitors should have one end close to the chip pin (pin 7) and the other end close to the chip's ground (pins 4/5). 4. The LDO external capacitor (10μF) should have the shortest possible path from the LDO (pin 9) to AGND (pin 12). 5. The copper trace from the chip's BATT pin to the positive battery terminal needs to carry a large current; this section should be as short and thick as possible. A 0.1μF and a 22μF surface-mount capacitor need to be placed from BATT (pin 16) to ground. One end of the capacitor should be close to the pin (pin 16), and the other end should form a good loop with the chip's ground. 6. Reserve an RC circuit to ground at the SW terminal (pins 2/3). (Generally, no component needs to be placed; it can be added if required during certification).
TX5818 Product Manual V1.0-2403 (2).pdf
PDF_Lithium Battery Management 2-3 Serial-TX5818 Functional Test Board.zip
Altium_Lithium Battery Management 2-3 Serial-TX5818 Functional Test Board.zip
PADS_Lithium Battery Management 2-3 Serial-TX5818 Functional Test Board.zip
BOM_Lithium Battery Management 2-3 Serial-TX5818 Functional Test Board.xlsx
91819
Voltmeter and Ammeter
[Voltage and Current Meter Training Camp] Voltage and Current Meters Based on LCSC GeoStar CW32
Project Overview:
This project is based on the CW32F030 digital voltmeter and ammeter, capable of detecting voltages from 0-30V and currents from 0-1.5A. A calibration function is included to reduce errors.
Project Functions:
This design is based on the LCSC CW32F030C8T6 development board and features three independent buttons: mode switch, calibration, and return to main interface (measurement mode). It enables wide-range voltage measurement (0-30V) and current measurement (0-3A) with an accuracy of two decimal places. Multi-stage calibration improves measurement accuracy. Two LEDs differentiate the operating status and indicate calibration completion through different flashing patterns. A 0.96-inch OLED screen displays the voltage and current measurement results in real time.
Project Parameters:
This design uses the SE8550K2 LDO chip with a maximum input voltage of up to 40V as the power supply chip, considering both high supply voltage conditions and avoiding the ripple interference introduced by the DC-DC converter, while also reducing costs. The
LCSC CW32F030C8T6 development board is selected as the control board, featuring a wide operating voltage range, strong anti-interference capabilities, and a better ADC—a 12-bit high-speed ADC—along with multiple Vref reference voltages.
This design uses a 0.96-inch OLED display module, displaying the current mode at the top and the current voltage and current measurement results or calibration target below.
When the mode is switched or the calibration is completed, a corresponding LED lights up or flashes to remind the user. A
voltage and current analog test circuit is designed for easy learning and debugging (R0 sampling resistor is not soldered).
Principle Analysis (Hardware Description):
This project consists of the following parts: power supply section, voltage sampling circuit, current sampling circuit, analog voltage measurement and calibration auxiliary circuit, analog current measurement and calibration auxiliary circuit, and OLED display circuit.
Power Supply Circuit:
The SE8550K2 LDO chip with a maximum input voltage of 40V is used as the power supply chip, which can stably output 5V.
Voltage Sampling Circuit
: The voltage divider resistors in this project are designed as 220K+10K, therefore the voltage division ratio is 22:1 (ADC_IN11). With an ADC reference voltage of 1.5V, the maximum measurable voltage is 30V (1.5V 23).
Current Sampling:
This project uses a low-side current sampling circuit for current detection. The low-side of the sampling circuit shares a common ground with the development board's meter interface. The sampling resistor (R0) in the circuit is 100mΩ, and the maximum sampling current is 3A. By measuring the voltage across the sampling resistor (ADC_IN12), the corresponding current is calculated. When the current through the sampling resistor is 10mA, the voltage across the resistor is measured as 1mV.
The analog voltage measurement and calibration auxiliary circuit
does not require soldering R0*.
The analog voltage measurement channel allows for voltage simulation by adjusting the adjustable resistor RP1 without soldering the sampling resistor R0 and shorting JP1 with a jumper cap. The voltage is then acquired via an ADC.
The analog current measurement and calibration auxiliary circuit
works similarly.
(OLED display circuit
physical diagram
measurement diagram)
PDF_Voltage and Current Meters.zip
Altium_voltmeter_currentmeter.zip
PADS_Voltage and Current Meter.zip
BOM_Voltage and Current Meter.xlsx
91820
XDS110 test probe
The Ti XDS110 is a low-cost emulator that offers 12MHz JTAG speed while maintaining a low cost and supporting both ARM and Ti proprietary devices. The XDS110's hardware design is derived from the LP-EXP432E401Y.
Project Overview:
The TI XDS110 is essentially an open design applicable to many scenarios, such as Keil MDK, IAR Embedded Studio, OpenOCD, TI CCS Studio, etc. This project is compatible with the J-Link shell and features CMSIS-DAP and TI's proprietary JTAG download and debugging capabilities. It has been tested with devices such as the TI C2000 TMS320F28035, MSP432P401YT, and STM32F401CCU6, and theoretically supports all ARM Cortex processors and most TI DSP devices, as well as mmWave SoCs or Wireless MCUs.
The XDS110 integrates a virtual serial port with a speed of at least 115200 MHz, a significant improvement over the J-Link v9. It provides a relatively high-speed serial port for convenient debugging without requiring a dedicated USB-UART chip. This project is based on the LP-EXP432E401Y schematic with slight modifications, and the level conversion circuit is based on the ACTG schematic with slight modifications. It supports downloading and simulating 1.8V, 3.3V, and 5V MCUs.
This project has a standard Ti-20 JTAG interface, allowing direct connection to development boards compatible with the Ti-20 JTAG interface. An adapter board allows downloading and simulating (most DSP devices) for development boards with the Ti-14 JTAG interface. It also supports Cortex Debug and ARM Serial Wire Debug interfaces. The adapter board is open-source at another link. The
original JTAG connector was a mirror image; this has been fixed in the new version.
The adapter board is open-source
, but the KiCAD project cannot be open-sourced on OSHWHub; please visit GitHub.
Important Notes:
All resistors and capacitors in this project use 0603 packages for easy hand soldering. It is strongly recommended to use a laser-cut stencil and a heated platform for soldering. The LQPF-128 package is extremely difficult to solder, often resulting in missing solder or bridging. SMT is preferred if possible. All components are on the front for easy soldering on the heated platform.
If SMT is used, pay attention to the orientation of the components.
The main chip can be an MSP432E401YT, TM4C1294NCPD, or TM4C129ENCPD; these three components are identical under the XDS110 firmware. According to GPT and other sources, the TM4C129E is an enhanced version of the TM4C1294, and the MSP432E401Y is a low-power version of the TM4C series.
After successful XDS110 soldering, a bootloader needs to be flashed. The required firmware and bootloader are integrated into TI CCS Studio and CCS Thiea, so ensure you have a working CMSIS-DAP or J-Link before prototyping and replicating.
After flashing the bootloader, the XDS110 operates in DFU mode. The firmware needs to be flashed using the xds110dfu tool. After inputting the necessary information, it will function normally.
The new firmware for the XDS110 supports Drag and Drop flash, but in practice, this is not very useful; standard mode is recommended. Drag and Drop flash only supports MSP432, Tiva, and C2000 series devices.
The board has a JTAG interface for the XDS110, and an SWD interface can also be used. If using SWD, connect SWDIO to the TMS and SWCLK to the TCK. It can be flashed using MCU Prog or J-Flash.
Different target levels can be selected using jumpers on the board.
Firmware flashing steps:
First, use other hardware such as J-Link, DAPLink, XDS110, etc., and flash the bootloader using MCU Prog, Jflash, Uniflash, or OpenOCD. Open
the command prompt and navigate to the XDS110 firmware folder in CCS
... `uscifxds110$ ./xdsdfu.exe -f ./firmware-xxxx.bin -r`
Testing shows that not changing the XDS110 serial number may cause problems in certain specific places. When connecting a normally functioning XDS110
... `uscifxds110$ ./xdsdfu.exe -m`
Enter DFU mode
... `uscifxds110$ ./xdsdfu.exe -s ME401023 -r`
This serial number is the serial number of the LP-EXP432E401 LaunchPad's onboard XDS110 probe.
You can use `xdsdfu -c ?` The command displays the
modes supported by XDS110, which can be switched arbitrarily. Contact information
: https://github.com/DCZYewen
contact@stu.hebust.edu.cn
Screenshot of successful operation.
The successfully created XDS110 probe can work in OpenOCD with CMSIS-DAP configuration or using XDS110 configuration.
Successful debugging of STM32F103C6 is shown
in the finished product image.
It is recommended to use this inexpensive debugging probe to flash the bootloader.
XDS110-Debug-Probe_Gerberfiles.zip
PDF_XDS110 test probe.zip
Altium_XDS110 test probe.zip
PADS_XDS110 test probe.zip
BOM_XDS110 test probe.xlsx
91822
CH340 Console Module
Simple, practical, stable, driver-uninterrupted, and low-cost switch console port communication module
This console communication module uses the ultra-stable CH340 solution and is compatible with Win11 systems.
The reason for making this: I bought a switch with a console port to play around with, but found that the console cables on the market were not very reliable. Those using the PL2303 solution couldn't install drivers on Win11, and on Win7, the drivers would drop frequently, requiring a restart to fix. Console cables using the FT232 solution were extremely expensive. After researching the working principle and communication levels of the console port, I decided to build my own better and cheaper console communication module.
Features: Made using the CH340N USB-to-TTL chip and MAX232, it has a simple structure, stable operation, and low cost. Only one A-to-C data cable and one network cable are needed to enable communication between the computer and the switch's console port.
Usage:
1. Prepare an A-to- C data cable... C. Data cable and a cable of length
2. Since the Console port uses RS232 level communication, which involves high voltage, hot-plugging the RS232 level port while it is powered on can easily damage the port circuit. It is recommended to first connect the module's network port to the switch's Console port using a network cable, and then use A to... 3. Connect the computer's USB-A port to the Type-C port on the module using the C data cable. 4.
After configuring SecureCRT and other software to suit the switch's communication parameters, you can communicate with the switch's Console port.
5. After completing communication, it is recommended to disconnect the USB connection first, then disconnect the physical connection of the Console port (for the same reason as point 2).
Friendly Links
: Demonstration (Bilibili): One-click link to Bilibili
CH340 Official exe Driver: One-click link to official download
Important Reminders
: 1. Because the Console port uses RS232 level communication, the voltage is relatively high (-9V, +9V). Hot-plugging RS232 level ports while powered on can easily damage the port circuitry. Recommended connection order: Console port → USB; Disconnection order: USB → Console port.
2. The indicator lights on the network port are only used to show the active status of the RX and TX communication lines and are unrelated to the network connection status.
3. Do not mistake this device for a USB wired network card and attempt to establish a network connection using it (if you can't even distinguish this, there's no need to be a network engineer or have a need for this module).
4. This device's network port is only allowed to connect to the switch's Console port (this is the purpose of this module's design). It is forbidden to connect this device's network port to any other device's regular network port or PoE port. [Image of the device
itself connected to the switch; image of communication results with the switch (9600 baud rate)]
PDF_CH340 Console module.zip
Altium_CH340 Console module.zip
PADS_CH340 Console module.zip
BOM_CH340 Console module.xlsx
91823
A niche embedded learning development board based on STC89C51
An embedded learning board based on the STC8H8K64U chip, suitable for people who want to use their brains a little but don't want to think too much.
Project Introduction:
This project is an embedded learning development board based on the 51 microcontroller, using USB-ISP mode for program download.
Project Functionality
: This design is an embedded learning board based on the STC8H8K64U microcontroller; it features four user-defined buttons, the functions of which must be determined by the user through corresponding code; it also has eight LEDs as running lights, which can be implemented through code to achieve a running light effect, and with further learning, a breathing light effect can be achieved. The onboard 44-matrix keypad can also be customized to perform many functions, making it suitable for beginners; additionally, an onboard thermistor, through the microcontroller's ADC, can be used to collect ambient temperature data, sufficient for use as the main controller in various systems.
Principle Analysis (Hardware Description):
This project uses the manufacturer's minimum chip system, plus LED lights, a matrix keypad, a download interface, user-defined buttons, and a thermistor. The microcontroller used in this project can be directly powered by a 5V power supply, so only a Type-C interface is included for power supply and downloading; no separate power supply is designed for the chip. The temperature acquisition uses a negative temperature coefficient thermistor, which can obtain the relationship between the sampling voltage and the ambient temperature according to the temperature curve, and is used to obtain the ambient temperature value. In addition, all IO of the microcontroller is brought out, and more peripherals can be connected.
Software code
include "led.h"
int i = 0;
float ls[8] = {0xFE,0xFD,0xFB,0xF7,0xEF,0xDF,0xBF,0x7F};
void LED_liushui(int dir)
{
if(dir == 1)
{
for (i=0;i<=7;i++)
{
P2 = ls[i];
delay_ms(100);
}
}
else if(dir == 2)
{
for (i=0;i<=7;i++)
{
P2 = ls[7-i];
delay_ms(100);
}
}
}
Simple running light code design, which will be updated later to make a small project
physical picture of ambient temperature acquisition.
video_20241008_164911_edit.mp4
PDF_A Niche Embedded Learning Development Board Based on STC89C51.zip
Altium - A niche embedded learning development board based on STC89C51.zip
PADS - A niche embedded learning development board based on STC89C51.zip
BOM_A Niche Embedded Learning Development Board Based on STC89C51.xlsx
91825
electronic
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