TF card extension board based on AGB-E05-01 board frame

Domestic Shell - Left Support.stl

Domestic Shell - Right Support.stl

Printed casing .3mf

PDF_TF Card Extension Board Based on AGB-E05-01 Board Frame.zip

Altium_TF Card Extension Board Based on AGB-E05-01 Board Frame.zip

PADS_TF Card Extension Board Based on AGB-E05-01 Board Frame.zip

BOM_TF Card Extension Board Based on AGB-E05-01 Board Frame.xlsx

94394

45° Triangle Ruler - NFC - with AEDL logo

The core work involved coupling the NFC function to the triangle plate primarily consisted of designing and simulating the irregularly shaped coil. After soldering, the NFC function was tested and found to be normal, with the deviation between the simulated and actual inductance values ​​being acceptable.

The core work involved coupling the NFC function to the triangular plate, specifically designing and simulating the irregularly shaped coil. After soldering, the NFC function tested and was found to be normal. The deviation between the simulated and actual inductance values ​​was acceptable. The
simulated inductance value was 2.75uH, and with a 50pF coupling capacitor, the resonant frequency was exactly the chip's operating frequency.
The measured inductance value was 3.56uH. My instrument has some issues and isn't very accurate, and the maximum frequency is only 1MHz… At least the inductance value wasn't that far off. The
NFC function test passed. It was also discovered that the coupling capacitor doesn't need to be used.
 
 
 

PDF_45° Triangle Ruler_NFC_with AEDL logo.zip

Altium 45° Triangle Ruler NFC with AEDL Logo.zip

PADS_45° Triangle Ruler_NFC_with AEDL logo.zip

94395

Isolated USB hub/to-485/to-Ethernet port

USB 2.0 HUB + RS485 + 100M Ethernet port using WCH domestic conversion chip (with 3D shell design)

The WCH domestic conversion chips used in this product
include: a USB hub chip (CH334, a USB to 4-port hub chip, see https://www.wch.cn/products/CH334.html);
a USB to serial port chip (CH9101, a VCP/CDC serial port chip, see https://www.wch.cn/products/CH9101.html);
a USB to Ethernet chip (CH397, a 100M network card chip, see https://www.wch.cn/products/CH397.html);
and a USB current limiting power distribution switch chip (CH217, which can be used in conjunction with CH334 for control). See https://www.wch.cn/products/CH217.html for details.
The isolated RS485

uses the Nsi8241 isolation chip to isolate the TTL serial port from the RS485, achieving 3k~8kVrms level isolation withstand voltage.

https://www.novosns.com/general-digital-isolator-1370
has been simply verified.
Connecting to a USB hub, emulator, network cable, and RS485,
actual tests show:
1. Serial port transmission and reception are normal;
2. Emulator debugging at 10MHz is normal;
3. Network port connection is normal and can connect to the host computer.
The 3D shell design uses a professional EDA version
to design the three-view diagram, which is simple and convenient. Combined with real-time preview of the PCB 3D model, it even eliminates the need to measure the actual dimensions. The actual prototyping effect is also very accurate. (The discrepancy between the image and the actual product on the cover is due to the initial design not considering the shell thickness. Components did not extend beyond the board edge, resulting in the interface being separated by the shell by 3mm. On some devices, the USB port was too shallow and not securely connected. The PCB and shell design has been modified to make the overall design more reasonable.)
A minor issue: when the shell is configured as a top and bottom shell, the inner wall cannot be cut with a separate slot. The USB port is designed to fit into the slot on the inner wall, requiring manual cutting to remove the connecting portion.