Enter the thermal voltage, the depletion layer capacitance, and the gate-oxide capacitance into the Subthreshold Swing Calculator. The calculator will evaluate the Subthreshold Swing.

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## Subthreshold Swing Formula

The following formula is used to calculate the Subthreshold Swing.

Ss = ln(10) * kt/q * (1 + Cd/Cox)

Variables:

- Ss is the Subthreshold Swing ( )
- kt/q is the thermal voltage
- Cd is the depletion layer capacitance
- Cox is the gate-oxide capacitance

## How to Calculate Subthreshold Swing?

The following steps outline how to calculate the Subthreshold Swing.

- First, determine the thermal voltage.
- Next, determine the depletion layer capacitance.
- Next, determine the gate-oxide capacitance.
- Next, gather the formula from above = Ss = ln(10) * kt/q * (1 + Cd/Cox).
- Finally, calculate the Subthreshold Swing.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem:**

Use the following variables as an example problem to test your knowledge.

thermal voltage = 30

depletion layer capacitance = 14

gate-oxide capacitance = 30

Ss = ln(10) * kt/q * (1 + Cd/Cox) =** ** ?