https://doi.org/10.1351/goldbook.A00300
The ampere, symbol \(\rm{A}\), is the SI unit of electric current. It is defined by taking the fixed numerical value of the elementary charge \(e\) to be \(1.602\ 176\ 634\times10^{-19}\) when expressed in the unit \(\rm{C}\), which is equal to \(\rm{A s}\), where the second is defined in terms of ΔνCs.