Component image generator

Part-DB can draw schematic-style pictures of passive components (resistors, SMD resistors and ceramic capacitors) from their value, and attach them to your parts. This is handy when you import a bulk assortment (for example a resistor or capacitor kit) that arrives with no pictures and only a value in the name — instead of blank thumbnails you get a clean, consistent illustration for every part.

There are two ways to use it:

  • the Value calculator tool, to draw a single component interactively, and
  • the Generate component images bulk action, to illustrate a whole selection of parts at once.

Both produce a lightweight, transparent SVG that is attached as the part’s picture (so it stays crisp at any size). The images are illustrations, not photographs — they show the colour-band code, capacitor code, or SMD marking together with dimension callouts.

Value calculator

Open Tools → Value calculator (requires the Value calculator permission). It has three tabs:

  • Resistor – enter a resistance (or pick the colour bands) and get a 4/5/6-band axial resistor. The tolerance, power rating and temperature coefficient (ppm) are reflected in the bands and body size.
  • SMD resistor – enter a resistance and package (0402, 0603, 0805 …) to get a chip resistor with the 3-digit, 4-digit or EIA-96 marking.
  • Capacitor – enter a capacitance to get a radial disc (or MLCC blob) ceramic capacitor with the printed code, optional voltage line and tolerance letter.

Every field is linked: editing the value updates the code (and vice-versa), and the picture redraws live. You can change the body colour, size, lead length and other appearance options.

Attaching to a part

When a part has no picture, its info page shows a Generate image button in the picture area. This opens the calculator in a dialog, pre-filled from the part’s value. Click Attach and the drawing is saved as the part’s picture without leaving the page.

Every tab also has a Download SVG button, which saves the currently shown picture as a standalone .svg file — useful if you just want the image itself (for a datasheet, label, or other document) without attaching it to a part.

Bulk “Generate component images”

To illustrate many parts at once, select them in any parts table and choose Actions → Generate component images.

Part-DB classifies each selected part as a resistor, SMD resistor or capacitor, reads its value and other properties, and shows a review table with a live preview for every part. You can adjust any value before writing, then:

  • Attach pictures – saves the generated image as each checked part’s picture, or
  • Write KiCad settings – writes the suggested KiCad symbol / footprint / reference prefix to each checked part (see EDA / KiCad integration).

Only parts without a picture are listed by default. If some of your selection already have a picture, a notice offers to re-generate / overwrite them (see Overwriting).

What is auto-detected — and how to get the best results

Each property is read from the part’s parameters first, then from its name and description. A part is only listed if it has no picture yet and a value can be read from it. To improve detection, add any of the following (a plain CSV import usually only fills the name/description, so putting the value in the name is the most reliable option):

Property Add a parameter named… …or write in the name / description
Value (required) Resistance / Capacitance (unit Ω or F) 10nF, 0.1µF, 4n7 · 4k7, 470R, 10k, 1M
Rated voltage (capacitors) Voltage 50V, 100V
Tolerance Tolerance ±5%, 1%, 0.1%
Power (through-hole resistors) 0.25W, 1/4W, 1W
Temp. coefficient (resistors) 50ppm, ±25 ppm/°C
Lead pitch (capacitors) Pitch / RM / Lead spacing pitch 5mm, RM5
Body diameter (capacitors) Diameter ⌀5mm
SMD size (resistors) the assigned footprint 0402, 0603, 0805, 1206, …
Body colour blue body, beige, green, …

How the properties are drawn depends on the component type, matching real-world conventions:

  • Capacitor – tolerance shows as the letter after the code (104K = ±10%); voltage as a printed line.
  • Through-hole resistor – tolerance and temperature coefficient are colour bands; power sets the body size.
  • SMD resistor – tolerance is expressed by the marking system (4-digit for 1 %, 3-digit for looser); power/voltage are not printed on a chip, so its size comes from the package instead.

Overwriting existing pictures

By default, parts that already have a picture are skipped. Use the Re-generate / overwrite button to include them anyway. When you then attach a picture to such a part, the new image becomes the part’s preview and replaces any previously generated image — manually uploaded photos are kept.