SOP & POS FormsTurning a truth table into a canonical expression, by minterms or by maxterms.Electrical EngineeringBoth forms describe the same function; only the cost differs.1Write the truth tableOne row per input combination, listed in binary counting order.2For sum of productsTake every row that outputs 1 and write its minterm as a product.3Build the sumOR those minterms. Complement any input that is 0 in that row.4For product of sumsTake every row that outputs 0 and write its maxterm as a sum.5Build the productAND those maxterms. Complement any input that is 1 in that row.SOP is cheaper when few rows output 1, POS when few output 0. Countthe rows before choosing which form to expand.SOP & POS Formslearnposters.com
SOP & POS Forms — printable engineering wall chart from LearnPosters. Free vector PDF, US Letter and A4.

SOP & POS Forms, step by step

Both forms describe the same function; only the cost differs.

  1. Write the truth tableOne row per input combination, listed in binary counting order.
  2. For sum of productsTake every row that outputs 1 and write its minterm as a product.
  3. Build the sumOR those minterms. Complement any input that is 0 in that row.
  4. For product of sumsTake every row that outputs 0 and write its maxterm as a sum.
  5. Build the productAND those maxterms. Complement any input that is 1 in that row.

SOP is cheaper when few rows output 1, POS when few output 0. Count the rows before choosing which form to expand.

Questions about the SOP & POS Forms poster

What’s on the SOP & POS Forms poster?
5 numbered steps. Both forms describe the same function; only the cost differs. Write the truth table — One row per input combination, listed in binary counting order.; For sum of products — Take every row that outputs 1 and write its minterm as a product.; Build the sum — OR those minterms. Complement any input that is 0 in that row.; For product of sums — Take every row that outputs 0 and write its maxterm as a sum.; Build the product — AND those maxterms. Complement any input that is 1 in that row.. SOP is cheaper when few rows output 1, POS when few output 0. Count the rows before choosing which form to expand.
Who is the SOP & POS Forms poster for?
SOP & POS Forms belongs to the Electrical Engineering section rather than to a school year, because engineering is not something one grade owns. Anyone learning digital logic can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the SOP & POS Forms poster?
Use it as the bridge from a specification table to something you can actually build. A wall chart earns its place by being glanceable from where the work is happening, so SOP & POS Forms belongs on the wall where that engineering work actually happens, within glancing distance, rather than filed away.
What other posters go with SOP & POS Forms?
Adders, Boolean Algebra and Counters & Registers sit alongside SOP & POS Forms in the Electrical Engineering section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.AddersBoolean AlgebraCounters & Registers
Is the SOP & POS Forms poster free to download and print?
Yes. SOP & POS Forms downloads as a free PDF with no account, no email and no watermark, like everything else in the Electrical Engineering section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the SOP & POS Forms poster print at?
SOP & POS Forms is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of SOP & POS Forms loses nothing.Printing guide

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