Linear Regulators

Compared with SMPS LED drivers, linear LED drivers are on the opposite side. The linear LED driver owes its name to the linear regulator which plays a similar role to a switch regulator in a switching power supply but in a completely different way. A linear regulator operates by controlling the voltage drop across a pass element biased in the linear region, while the switch regulator operates in saturation and cut-off regions of the transistor. Unlike its switching cousin which switches between the full on (cut-off) or off ( saturation) mode at high frequency, a linear regulator always operates in the linear region in a partially on mode, with the degree of conductivity determined by a negative feedback loop. By its nature a linear regulator has a fairly straightforward design. It doesn't produce high frequency switching noise and no energy storage elements are used in the circuit. Therefore, linear regulators pose significantly less design challenges than switch regulators with regard to cost control, reliability engineering and EMI filtering.