LDO current-limit knee
7 parts
A 9 V rail feeds a 5 V low-dropout regulator while time-delay switches step the load: 100 Ω from the start, a second 100 Ω at 2 ms, a 50 Ω at 4 ms. The first step doubles the current — 50 to 100 mA — and the output holds 5.0000 V; the second asks for 200 mA, past the 150 mA limit, so the regulator gives up the voltage to hold the current, and the output drops to 3.75 V, right where the 150 mA limit line meets the 25 Ω composite load. Behavioural macromodel, stated: an ideal-regulation envelope with a PWL current-limit knee solved inside Newton; the GND pin carries 0 A and nothing thermal is modelled.
- V1 9V
- LDO1 →5V
- R1 100Ω
- TDSW1 2ms
- R2 100Ω
- TDSW2 4ms
- R3 50Ω
