Hello,
I am also looking for schematics standards.
I guess there are some military ones.
For some time already, I am designing with hierarchical schematics,
top-down blocks or modules.
For numbering, the first level blocks are numbered 100 (power supply),
200 (sensor module), 300 (outputs)...
Inside block 100, the components are U103, R124, C102.
Suppose that sensor module, block 200, have another low level partition,
say DC sensing block 2000, and AC sensing block 2100.
Inside the AC sensing block, there are R2102, C2114, U2101, etc.
If a module has more than 99 resistors, for example, it is reasonable to
partitioning it.
This method has been working fine for more than three years here, into a
fast pacing modifications environment, without disrupting organization
and with less pain for management project control.
With some practice, you know that R146 is a resistor at the power supply
module, for example, and never will be at the sensing block.
The component ref number also carries a block info and location guidance
on it. It is not only a linear up counting.
On big schematics, changing numbers each day during development could be
a mess to the engineer memory.
Sure, the multidigit numbering could consume space on silk screen or
even clutter it. At this case, it is better to not print ref numbers.
Maybe some "block fence with reference" on the silk screen.
This way, some could be *almost* sure that R102 is inside the block 100
"fence". Some blocks may be spread over board...
Not all blocks must be "fenced". The very important ones, lefting others
by deduction.
But if you are consistent, the field technicians will not flame you.
Give them an enlarged print of the silk screen with the numbers and the
schematics.
Well, it is a suggestion.
Does anyone have another working good idea to help us?
Some official standard to suggest?
Best regards.
--
Andre Felipe Machado
Embedded Systems Design Engineer
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