Homemade astronaut-themed thermometer and hygrometer

BOM download

PCB_Shell_2022-09-23.pdf

PCB_Shell_2022-09-23.json

Shell_2022-09-23.pcbdoc

Gerber_Shell_2022-09-23.zip

PCB_PCB_PicoIdeal_2022-09-23.pdf

PCB_PCB_PicoIdeal_2022-09-23.json

PCB_PicoIdeal_2022-09-23.pcbdoc

Gerber_PCB_PicoIdeal.zip

Schematic_Homemade astronaut theme thermometer and hygrometer_2022-09-23.pdf

SCH_Homemade astronaut theme thermometer and hygrometer_2022-09-23.json

Sheet_1_2022-09-23.schdoc

61646

Homemade linux small computer

Introduction: Allwinner V3S main control, board shape and screw holes compatible with Raspberry Pi

Introduction
The main control adopts Allwinner V3S, single-core Cortex-A7, 64MB memory
board with rj45 network port, headset, microphone, TF card slot, USB, 40pin RGB screen interface
4.3-inch 800x480 resolution screen
casing is acrylic (see design drawing Shell, the DXF file can be exported and can be customized and cut in a certain treasure), M2.5 screw fixing
demonstration video
https://www.bilibili.com/video/BV19r4y1M7cf
physical picture

BOM download

PCB_Shell_2022-09-23.pdf

PCB_Shell_2022-09-23.json

Shell_2022-09-23.pcbdoc

Gerber_Shell_2022-09-23.zip

PCB_PCB_Allwinner_V3s_2022-09-23.pdf

PCB_PCB_Allwinner_V3s_2022-09-23.json

PCB_Allwinner_V3s_2022-09-23.pcbdoc

Gerber_PCB_Allwinner_V3s.zip

Schematic_Homemade linux small computer_2022-09-23.pdf

SCH_Homemade linux small computer_2022-09-23.json

Sheet_1_2022-09-23.schdoc

61647

TPA6120 Portable Headphone Amplifier V3.0

Introduction: A portable headphone amplifier powered by USB

Version update history:
V1.0-->First version, only includes the 6120 headphone amplifier and power supply (serious problems exist)
V1.1-->Added 2706 USB interface, 1754DAC, and audio source switching circuit (still has serious problems, this The plan has been scrapped)
V3.0 (pre-release) --> Cut off the low-performance USB decoding part, optimize the circuit design, and reduce the size. It is currently being produced. I hope it will not overturn.
Introduction
       This is a USB-powered Desktop headphone amp, compact in size, easy to carry and store. The headphone amplifier chip is TPA6120A2, the input buffer operational amplifier is NJM4580,
the TPS65131 is used to generate positive and negative 12V power supplies, and an 8-pin potentiometer is used for switching on and off and adjusting the volume, which can drive headphones with an impedance of 16Ω~600Ω.
V3.0 PCB design drawing, the PCB size is reduced from the previous generation’s 80*50 to 60*40 (the extra 1.6mm on each side is used to fit into the 60*19*46 casing. The
matching front and rear panels are currently being designed Center)
3D simulation diagram:
physical display part
(to be added)
 

BOM download

PCB_PCB_TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.pdf

PCB_PCB_TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.json

PCB_TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.pcbdoc

Gerber_PCB_TPA6120 Portable Headphone Amplifier V3.0.zip

PCB_Potentiometer Daughter Board_2022-09-23.pdf

PCB_Potentiometer daughter board_2022-09-23.json

Potentiometer daughter board_2022-09-23.pcbdoc

Gerber_potentiometer daughter board_2022-09-23.zip

PCB_Rear Panel V3.0_2022-09-23.pdf

PCB_Rear Panel V3.0_2022-09-23.json

Rear panel V3.0_2022-09-23.pcbdoc

Gerber_Rear Panel V3.0_2022-09-23.zip

PCB_Front Panel V3.0_2022-09-23.pdf

PCB_Front Panel V3.0_2022-09-23.json

Front panel V3.0_2022-09-23.pcbdoc

Gerber_Front Panel V3.0_2022-09-23.zip

PCB_PCB_TPA6120 Portable Headphone Amplifier (Abolition)_2022-09-23.pdf

PCB_PCB_TPA6120 Portable Headphone Amplifier (Abolition)_2022-09-23.json

PCB_TPA6120 Portable Headphone Amplifier (Abolition)_2022-09-23.pcbdoc

Gerber_PCB_TPA6120 Portable Headphone Amplifier (Abandoned Case).zip

Schematic_TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.pdf

SCH_TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.json

TPA6120 Portable Headphone Amplifier V3.0_2022-09-23.zip

61648

CH9340 USB to serial port module

Introduction: USB to serial port module based on CH9340K

The mini version of the CH9340 USB to serial port module uses CH9340K as the conversion chip, without the need for an external crystal oscillator or driver.
The TYPE-C port is connected to the computer, and the 5-pin header leads to the +5V power supply, UART serial port (RXD/TXD), and ground (GND). The wiring sequence is as follows:
onboard RX/TX indicator light. When sending data, the red LED flashes; receiving When data is being read, the green LED flashes
onboard 0.5A self-recovery insurance. The original design used an ESD array as electrostatic protection, but it was removed from the PCB due to size restrictions: (
The PCB size is 14mm*22mm, which is better than the online solution using this chip. It should be smaller.
Because this chip uses the system’s own CDC driver, many functions cannot be used normally, but it is no problem to download the program to the microcontroller. If necessary, it is recommended to change to CH340K, VCP driver (only 4 and 5 pins). Definitions are different)
PCB size diagram:
Physical picture (there are no curved pins on hand, use straight ones instead)
Connect to the computer and send data:
When sending data, the TX light flashes.
Use STC-ISP to download a program to 89C52, and disconnect the target microcontroller first. After powering on, the pups will be born normally.
 

CH9340SER.EXE

BOM download

PCB_PCB_CH9340 USB to serial port_2022-09-23.pdf

PCB_PCB_CH9340 USB to serial port_2022-09-23.json

PCB_CH9340 USB to serial port_2022-09-23.pcbdoc

Gerber_PCB_CH9340 USB to serial port_2022-09-23.zip

Schematic_CH9340 USB to serial port module_2022-09-23.pdf

SCH_CH9340 USB to serial port module_2022-09-23.json

Sheet_1_2022-09-23.schdoc

61649

electronic