One Driver Can Feed a Limited Number of Bases - Semiconductor Physics and Transistor Switching Step by Step

Base currents add, and equality to the driver limit still passes.

Base currents add, and equality to the driver limit still passes. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Four half-ampere bases need two amperes

Four transistor bases at 1/2 A each sum to 2 A, below the 3 A driver limit.

4\cdot {1\over 2}\ \text{A}=2\ \text{A}\le 3\ \text{A}

Equality also passes by the stated convention

Six half-ampere bases sum exactly to the 3 A limit, and equality is accepted.

6\cdot {1\over 2}\ \text{A}=3\ \text{A}