RAK3172 PCB land pattern recommendation missing total pad length dimension

LPWAN Modules / EVBs RAK3172
1

Hello-

I’m creating a PCB footprint for the RAK3172. During this effort, I realized the datasheet fails to show the complete footprint dimension for the recommended pads.

I can see the width of each pad is recommended to be 0.7mm. I can also see each pad should extend 0.8mm beyond the package dimension. But the “total” pad length can NOT be determined with the given layout drawings.

I need to know how long you recommend the pad should be under the package (or the total length of the pad).

Thanks!

2

Hi @loradev54 , I will ask the hardware team about it. I’ll get back to you asap.

3

Any updates on the PCB Footprint? Is this available for download?

4

Hi @tremmert ,

Please use this drawing for the length of the pad. It should be 1.8mm. It still depends on you if you want to make it a bit longer if you are hand-soldering some prototypes. The docs will be updated after the Lunar New Year holiday.

image

5

3172 layout 一个转接板之后，接电源，接串口，AT指令无反馈，请赐教

6

Welcome to RAK forum @david.liu ,

I have to convert your message using google translate:

After an adapter board, connect the power supply, connect the serial port, AT command no feedback, please teach

If there is no reply on AT command, please make sure that

  1. You selected the right COM port number.
  2. The jumper wires going to the USB-UART converter is ok (if you are using the breakout board).
  3. UART connections are correct.
  4. Baudrate is 115200 (if using RUI3 firmware) and 9600 (if using the legacy 1.0.4 firmware).
  5. Try to execute at+run in case you are in boot mode.