Multichannel Layout - Topology mismatch problem

Layout
1

I’m building an FPGA board that needed several DC-DC supplies. I used hierarchical sheets, each sheet contains an identical copy of DC-DC step-down circuit. Since each supply has a different output level, the voltage divider resistor values has to be different, therefore the subsheets are instantiated from different sheet files (but with identical connection, footprint, etc). I’ve routed one DC-DC block, generated rule areas for all four blocks. The multichannel tool will report topology mismatch for the DC-DC blocks.

图片
图片1920×1335 171 KB

I’m curious about two problems:

  1. Do I have to instantiate two subsheets from the same file, in order to make multichannel work? If so, what should I do to make different sheets have a different voltage divider?
  2. Is there any chance to see what “topology” is really mismatched? Shall I make this a wishlist item?

Thanks for all your assistance.

Minimal reproduce project archive:
replicate_dcdc.zip (810.3 KB)

Version:

Application: KiCad PCB Editor arm64 on arm64

Version: 9.0.0, release build

Libraries:
	wxWidgets 3.2.6
	FreeType 2.13.3
	HarfBuzz 10.2.0
	FontConfig 2.15.0
	libcurl/8.7.1 (SecureTransport) LibreSSL/3.3.6 zlib/1.2.12 nghttp2/1.63.0

Platform: macOS Sequoia Version 15.3.1 (Build 24D70), 64 bit, Little endian, wxMac
OpenGL: Apple, Apple M4, 2.1 Metal - 89.3

Build Info:
	Date: Feb 19 2025 13:05:44
	wxWidgets: 3.2.6 (wchar_t,wx containers)
	Boost: 1.87.0
	OCC: 7.8.1
	Curl: 8.7.1
	ngspice: 44.2
	Compiler: Clang 16.0.0 with C++ ABI 1002
	KICAD_IPC_API=ON

Locale: 
	Lang: en_GB
	Enc: Simplified Chinese (Mac OS)
	Num: 1,234.5
	Encoded кΩ丈: D0BACEA9E4B888 (sys), D0BACEA9E4B888 (utf8)
2

Topology mismatch problems have been discussed recently, please do a search.

3

It’s a known bug. Will be likely fixed in 9.0.1. More verbose messages explaining the “topology” are scheduled for later releases - we need to translate them.

T.