Hi,
Can I know how to connect the blue circled resistance? I don't have that much experience in such thing.
Appreciate any help.
Showing me by drawing on the image will be highly appreciated.
The original schematic PDF is attached.
arduino-mega2560_R3-sch.pdf (47.1 KB)
"RN" stands for Resistor Network,. It is a single pack with multiple resistors and multiple pins.
You need to explain why you are asking how to install something that is already installed on a 2560.
Those are the unused elements of the resistor networks. The design of the Mega didn't require all four of the resistors, but it evidently still works out better from a manufacturing perspective to use the resistor network package than multiple individual parts. Here you can see RN2, with the "B" and "C" elements unconnected:
AGAIN,
WHY are you asking this question ?
If there are vacant resistor network pads you can
buy the correct size and populate them but why are you asking ? (it's obvious that if the pads are vacant , you can populate them)
raschemmel:
"RN" stands for Resistor Network,. It is a single pack with multiple resistors and multiple pins.
You need to explain why you are asking how to install something that is already installed on a 2560.
I'm designing a PCB that is based on AtMega2560 chip.
Then if you want to use all the network resistors just buy all the parts to populate them. What else is there to know ? (I am not sure why this hasn't occurred to you. Am I missing something that perhaps you haven't told us ?
Or, just use discrete 0402 or 0603 resistors and drop the 4x resistor pack. Might even make routing easier if you are making changes.
Thanks guys for your support.
I want to use 5 resistance (2pcs - 22ohm, 2pcs 10k, 1pcs 1k) just like the schematic but not network resistors, but I don't know how to connect them.
Those two signals appear to be the USB D+ and D- signals, I don't think you'd want to running other signals thru that resistor pack, which sits between the USB connector and the 16U2 that does the USB/Serial interfacing.
You have to add new parts to the schematic first with signal connections, then they show up on the board and you place and route signals to them. Are you perhaps a new Eagle user?
CrossRoads:
Or, just use discrete 0402 or 0603 resistors and drop the 4x resistor pack. Might even make routing easier if you are making changes.
Or 1206
but I don't know how to connect them.
The parts you circled on the schematic are not connected to anything, so there is no need to connect them to anything.
If one part is being used in a lack of four, the other three that are not needed appear on the schematic anyway.
CrossRoads:
Those two signals appear to be the USB D+ and D- signals, I don't think you'd want to running other signals thru that resistor pack, which sits between the USB connector and the 16U2 that does the USB/Serial interfacing.
Yes I'm new to PCB designing, I have just created 3 PCBs based on ATmega328, but now I'm trying to create one using AtMega2560. Actually I'm not using eagle, I use EasyEDA to order the PCB from JLCPCB with SMT service.
Good for your in tackling this :).
Grumpy_Mike:
The parts you circled on the schematic are not connected to anything, so there is no need to connect them to anything.If one part is being used in a lack of four, the other three that are not needed appear on the schematic anyway.
Aha, interesting. Thanks
I have one last question, the red circles in the attached pic. shares the same concept?
hsalame:
I have one last question, the red circles in the attached pic. shares the same concept?
Not as such - all four parts of RN4 are actually used in the circuit, while the bottom red circle refers to the common supply and ground connections to the whole board.
Expand!
Thank you very much guys.
