Schematic Review Checklists

Owned by Farris Matar
Last updated: 2023-06-29 by Stanley Hao
3 min read

This page is meant to provide a list of things that should be checked when reviewing the schematic for a PCB. It is the designer’s responsibility to check for ALL of the things below themselves, then assign others to review their schematic.

Part Reviews

  • Every single new part that was used in the PCB and added to the libraries must be reviewed by both the designer and one other person, following the Part Review Checklist. An exception can be made for ceramic capacitors and chip resistors

  • For each new part, create an Asana task under the project to request a review from someone. Be sure to include the manufacturer part number, symbol name, and footprint name, as well as indicate if the symbol, footprint, or both need to be reviewed.

  • If the reviewer notices any problems with the symbol or footprint, comments should go under the Asana task, and the problems will need to be resolved by the designer

Schematic Sheet Reviews

For each schematic sheet in the project, create an Asana task to assign someone to review the schematic sheet.

Sheet_Name.SchDoc (<Reviewer Name>)

It is up to the designer’s discretion as to what specifically should be reviewed for each schematic sheet. Generally, the sheets should be checked for clarity and correct implementation of all the circuitry

Generic Schematic Review Checklists

For each of the following checklists, create an Asana task to assign someone to check that ALL schematic sheets in the project adhere to the checklist.

Net Naming

All major nets named
No duplicate net names, or nets with multiple net names
Differential pairs end with _N and _P
Active low signals are indicated with either a “_n” at the end or with overbar notation (using a “\” character after each letter in the net name, i.e. E\N\)

Wiring and Connections

No 4 point connections
All unconnected pins have an ERC directive
Devices sharing an I2C or SPI bus must be simultaneously powered on/off (i.e. by powering them all off of the same power rail) - prevents unpowered devices from pulling the bus low
Lines that require pull ups are pulled up in exactly one place (not pulled up multiple times, or missing pull-ups)
Double check that any lines with high-resistance pull-ups/pull-downs (>100kOhms) will still receive sufficient current to drive the signal

Component Labels

ICs show part number
Resistors show resistance and power rating
Capacitors show capacitance and voltage rating
For capacitors, voltage rating is 2x higher than expected voltage for low-voltage nets (<12V), 1.5x higher for high-voltage nets (>12V)
Inductors show inductance and rated current
Ferrite beads show impedance @ frequency value
Diodes show part number, voltage rating, and current rating (if applicable). Exception is for LEDs, which only need part number

Design-for-Test (Schematic)

Sufficient GND test points. Each major circuit should have at least one GND test point nearby, preferably a loop or hook to allow clipping a GND reference for oscilloscope probes
All voltage rails have test points and an LED indicator
Enable/shutdown/reset/etc. lines for ICs have test points
Communication interfaces have test points (i.e. I2C, SPI, UART)
All sensor outputs have test points
Any other signals that might want to be checked during testing should have a test point