Why LEDs Need Current Regulation
An LED forward voltage varies with temperature. LEDs are current-driven devices.
Constant-Current Drivers
Regulates LED current precisely. Compensates for Vf variation. Needed for high-brightness lighting.
Constant-Voltage Drivers
Simple, low-cost. Used with pre-resistored LED strips. Inefficient — resistors waste power.
Selection Checklist
- Output current matched to LED specs
- Max output voltage margin
- Dimming: PWM vs analog
- Efficiency and thermal design