step-up-trades-current-for-voltage - Electronic Circuits XV: Transformers and Coupled Inductors Step by Step

A step-up case shows the same power ledger from the other direction. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Voltage can rise while ideal power stays fixed

The scan keeps primary voltage and primary current fixed. More secondary turns raise voltage and lower secondary current.

P=V_pI_p=V_sI_s

Higher secondary voltage carries lower secondary current

Every row keeps the primary side at the same exact power.

\begin{array}{c|c|c|c|c}N_s&V_s&I_s&I_p&P\\2&5\ \text{V}&3\ \text{A}&3\ \text{A}&15\ \text{W}\\4&10\ \text{V}&\tfrac{3}{2}\ \text{A}&3\ \text{A}&15\ \text{W}\\6&15\ \text{V}&1\ \text{A}&3\ \text{A}&15\ \text{W}\\\end{array}

A step-up transformer trades current for voltage

The larger secondary voltage is paired with smaller secondary current for the same ideal power.

5\ \text{V}\rightarrow15\ \text{V}\quad;\quad3\ \text{A}\rightarrow1\ \text{A}