SLVUBB4B User guide

SLVUBB4B November 2017 – February 2023

#T5147377-112 is a schematic of an isolated Type II compensation network with a Zener clamp.

Figure 12-5 Schematic of an Isolated Type II Compensation Network With a Zener Clamp

Closed loop error amplifier transfer function for isolated feedback.

Type II Isolated with Zener Clamp:

Equation 100.

\frac{{\hat{v}}_{c}}{{\hat{v}}_{o u t}} = - C T R (s) \times \frac{R_{P}}{R_{D}} \times G_{E A} (s) \times \frac{1}{1 + (\frac{1}{A_{O L}} + \frac{s}{ω_{B W}}) + (1 + G_{F B} (s))}

Equation 101.

G_{E A} (s) = \frac{A_{V M} \times \frac{ω_{Z E A}}{s} \times (1 + \frac{s}{ω_{Z E A}})}{(1 + \frac{C_{H F}}{C_{C O M P}}) \times (1 + \frac{s}{ω_{H F}})}

Equation 102.

G_{F B} (s) = \frac{A_{V M} \times \frac{ω_{Z E A}}{s} \times (1 + \frac{s}{ω_{Z E A}})}{\frac{R_{F B B}}{R_{F B B} + R_{F B T}} \times (1 + \frac{C_{H F}}{C_{C O M P}}) \times (1 + \frac{s}{ω_{H F}})}

Equation 103.

C T R (s) = \frac{C T R}{1 + \frac{s}{ω_{O P T O}}}

DC-Gain:

Equation 104.

A_{V M} = C T R \times \frac{R_{P}}{R_{D}}

Power Stage Designer uses a constant value of 1 for CTR.

Compensation zero:

Equation 105.

ω_{Z E A} = \frac{1}{R_{C O M P} \times C_{C O M P}}

Compensation pole:

Equation 106.

ω_{H F} = \frac{1}{R_{C O M P} \times C_{H F}}