Drop-Out Regulator

Multiple output power converters may not provide regulation that is good enough to meet the requirements of every output. The regulation of a single output of the converter may require some type of post regulation to meet the regulation requirements of that output. In many 

This circuit utilizes a MOSFET as a source follower. The MOS-FET is controlled by a TL431 shunt regulator integrated circuit. 

The dominant pole is created by the source impedance of the MOSFET, and the output capacitor. A second pole is created by the MOSFET s Ciss and its driving impedance. Therefore, the MOSFET 

File name Simulation Type of model SIMetrix run time (s) IsSpice run time (s) 

1 The SG1524 model was simulated in IsSpice and SIMetrix, RELTOL = 0.01, TMAX 50n 

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Figure 4.57 Simulated low drop-out regulator phase and gain margins. Note the...

Figure 4.60 Measured low drop-out regulator transient response.

Figure 4.67 Measured modified low drop-out regulator turn-on.

Figure 4.54 TL431 low drop-out linear regulator circuit.

Figure 2. ERPDU building blocks (a) rectifier, (b) DC limiter, (c) Low-Drop Out (LDO) regulator, (d) Band Gap Regulator (BGR).

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