Regulator Waste Current Limit Three-Row Scan - Electronic Circuits XIII: Power, Rectification, and Regulation Step by Step

Load current turns the same voltage drop into a waste-power limit check. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

1 A waste row

Input and output stay 7 V and 5 V. Load current 1 A makes waste 2 W against a 4 W budget, so margin is 2 W.

P_w=2\ \text{W},\quad m=2\ \text{W}

2 A waste row

Input and output stay 7 V and 5 V. Load current 2 A makes waste 4 W against a 4 W budget, so margin is 0 W.

P_w=4\ \text{W},\quad m=0\ \text{W}

3 A waste row

Input and output stay 7 V and 5 V. Load current 3 A makes waste 6 W against a 4 W budget, so margin is negative 2 W.

P_w=6\ \text{W},\quad m=-2\ \text{W}