Simple Rules of Thumb

Rules are given in order of priority.

• consistency

  • a single schematic should follow the same styling conventions

• passives to power rails should be vertical

  • i.e. i2c pullups and decoupling capacitors

• schematics should follow a logical left to right flow

  • input on the left, output on the right

• higher electrical potential (voltage) rails should be above lower voltage rails

• signal passives should be horizontal.

• show parameters for components

  • it should be obvious which parameter corresponds to which component based on proximity

• assign net names to all nets

  • see https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2179334174/Net+Naming+Guidelines?search_id=052284b0-d274-4574-8df2-a26d7db68438&additional_analytics=queryHash---a51cc39c53a8e798d08b313778664af8a01d96ef96e63930638853743f6b4d2a for further details

• minimize corners in schematic wires when possible

• components should be placed in the schematic near components they will be near in the layout when sensible

  • notably, decoupling capacitors should be placed in the schematic near the IC they’re decoupling as opposed to being on a different sheet with no specifying comment

    • see https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2178154501/Decoupling+Capacitors?search_id=be08defc-9cba-48a6-9283-64e3f906590c&additional_analytics=queryHash---0f1c3fed2128d86a807147c6bab7604e287482b1998d87d9ba440968c2c77c3f for further detail

• minimize length in schematic wires when sensible

• do not use excessive hierarchy

  • do not excessively nested schematic sheets

• minimize intersecting schematic wires when sensible

Why

• Standard

  • makes reviews easier

  • improves human readability

  • preparation for industry

  • reduce the probability of critical schematic mistakes

• We don't want to nitpick

  • If you have a reason for doing something slightly different it’s fine

  • there are a lot of edge cases these simple guidelines don't cover so do what’s best and call it a day

    • as long as you did something for a reason then it’s chill

    • do not do styling randomly/arbitrarily

Learning

The best way to learn is to look at schematics and see what you think is reasonable. Check out past WARG designs and see how they style their schematics. Not everything we do is perfect, but a lot of it is decent and a great starting place! Some good examples include:

• Single Servo Driver

• RPI Interface Rev C

External Lengthier Guides

• https://blogupvertercom.wordpress.com/2014/05/28/schematic-style-guide/

Further Info

• https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2308538389/Electrical+Terminology?search_id=c217c471-023e-40e3-9d9c-926786a57657

• https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2179334174

• https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2177859613

• https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2179465308

• https://uwarg-docs.atlassian.net/wiki/spaces/EL/pages/2682978317

Interpretation Information

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.