Edit part symbols

Flux is an AI hardware engineer. Flux can set up the schematic symbol of a part for you: the symbol style, the side of each pin, the pin groups, the sections, the pin order and the sub-symbols. You can also edit the symbol yourself in the Symbol tab of the part project.

A parametric symbol is drawn from the pin properties of the part. When you change a pin property, Flux draws the symbol again, and the symbol grows with the number of pins. The pin properties are Pin Orientation, Pin Group, Section, Terminal Order and Sub-symbol Designator Suffix. See Inspector properties.

Set up a parametric symbol for an IC

Ask Flux to do the full setup in one message. Flux reads the datasheet, sets the pin properties, checks the result, and shows you the final symbol.

Set up the symbol of this STM32 microcontroller as a parametric symbol. Put power, ground, reset and boot on the left and the ports on the right. Group the pins by function, add a section for each group, order the pins by pin number, and split power into its own sub-symbol.

Make a parametric symbol for this dual op-amp with sub-symbols U1.A and U1.B for the two amplifiers and U1.C for the supply pins. Put the inputs on the left and the output on the right.

Set up the motor driver symbol: logic inputs on the left, motor outputs on the right, supply and ground on top and bottom. Group the pins of each H-bridge and fix any Missing Parametric Symbol Properties check.

Lay out the display controller symbol with sections for Power, SPI, Parallel Bus and Control. Keep the data pins D0 to D7 in order and show me the symbol when you are done.

To set it up yourself:

Open the part project.
In the editor mode strip, select Add tab → Symbol. The Symbol tab shows each sub-symbol of the part side by side.
Select the part and, in the Inspector, set Symbol Style to Parametric.
Set the pin properties in the Symbol tab, the Pins table, or the Inspector, as the sections below show.

Put pins on a side

Move the supply and ground pins of the motor driver to the top and bottom of the symbol, and the motor outputs to the right.

Put the connector's signal pins on the right and its shield and ground pins on the left.

In the Symbol tab, drag a pin to another side of the symbol. Flux sets Pin Orientation of the pin to Left, Right, Top or Bottom. To move more than one pin, drag a box around the pins first, then drag one of the selected pins.

In the Pins table, you can also set the Orientation column of each pin.

Group pins and add sections

Group the microcontroller pins as Power, Reset and Boot, Debug, Port A and Port B, and add a section for each group.

Put the display's backlight pins in their own group, below the SPI pins.

Pins with the same Pin Group stay close together on one side. Pins with the same Section go in one labeled part of the symbol, with a divider between sections.

In the Symbol tab:

Drag a pin onto a group to add it to that group.
Drag a group to move all of its pins to another side or position.
Drag a section up or down to change the order of the sections.

In the Pins table, you can also set the Pin Group and Section columns.

Set the pin order

Order the port A pins from PA0 at the top to PA15 at the bottom.

Order the connector pins by pin number, with pin 1 at the top left.

In the Symbol tab, drag a pin up or down on its side, or between two groups. Flux sets Terminal Order for the pins on that side. In the Pins table, you can also set the Order column.

Split a symbol into sub-symbols

Split this quad op-amp into four amplifier sub-symbols and one power sub-symbol.

Move the microcontroller's power and ground pins into their own sub-symbol, U1.A, and keep the I/O pins in U1.B.

A part with sub-symbols shows one symbol for each Sub-symbol Designator Suffix, for example U1.A and U1.B. You can place each sub-symbol at a different location in the schematic.

In the Symbol tab:

Drag pins outside every symbol to make a new sub-symbol.
Drag pins onto another sub-symbol to move them to it.

In the Pins table, you can also set the Sub-symbol column.

Rename pins, sections, and groups

Rename the display pins to match the datasheet: SCL, SDA, RES, DC, CS and BLK.

Rename the motor driver sections to Logic, Bridge A, Bridge B and Supply.

In the Symbol tab, double-click a pin name, a section name or a group name. Type the new name, then press Enter. Press Escape to keep the old name.

Fix the Missing Parametric Symbol Properties check

Fix the Missing Parametric Symbol Properties check on this part. Give every pin a side, a group and a section from the datasheet.

The Missing Parametric Symbol Properties check lists the pins that have no Pin Group, Pin Orientation or Section. To see it, select the part and open Reviews in the Inspector. Select each listed pin and set the missing properties in the Symbol tab, the Pins table or the Inspector.

Use a standard or custom symbol

Use the standard N-Channel MOSFET symbol for this transistor.

Use the attached SVG as the symbol of this stepper motor, and map its pins to the motor coils.

Give this connector a custom symbol for each of its two rows, and keep the passives on their standard symbols.

Standard Symbol sets a standard schematic symbol, for example NPN Transistor, N-Channel MOSFET, Bridge Rectifier, Op-Amp or Optocoupler. The Part Type of the part also sets its symbol. See Part types.
To use your own drawing, add an SVG file in the Assets panel and select Set this as default symbol. To give a sub-symbol its own drawing, enter its suffix in Assign to Sub-symbol. Set Symbol Pin Position on each pin to place it on the drawing. See Inspector assets.
The Symbol tab shows custom symbols too. To edit the pin sides, groups and sections in the Symbol tab, set Symbol Style to Parametric.

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