17-07-2012, 04:29 PM
Low Dropout (LDO) Regulator
Low Dropout (LDO) Regulator.docx (Size: 87.29 KB / Downloads: 22)
AIM:
The goal of this experiment is to design a Low Dropout regulator using a general purpose Op-Amp and study its characteristics. We will also see that an integrated circuit family of regulators, called TLV700xx, is available for the purpose and study their characteristics. Our aim is to design a linear voltage regulator with high ef_ciency, used in low noise, high ef_ciency applications.
THEORY:
The switching activity exemplified by the PWM waveform is a source of noise. As a result, DC-DC converter of the previous chapter is not suitable for low noise applications. An LDO is better suited in such cases. An LDO circuit is shown in Figure. It uses a PMOS switch along with an Op-Amp so that power dissipation in Op-Amp is minimal. The efficiency of the LDO, defined as the ratio of the output voltage to input voltage, is high. The regulated output voltage is given by
VO=Vref (1+R2/R1)
RESULTS:
1. We have designed the LDO and we have plotted graph for load regulation and line regulation.