SLVUBB4 User guide

SLVUBB4B November 2017 – February 2023

#T5147377-105 is a schematic of a Type II transconductance compensation network.

Figure 12-3 Schematic of a Type II Transconductance Compensation Network

Type II Transconductance with feed-forward:

Equation 85.

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

Equation 86.

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

Type II Transconductance:

Equation 87.

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 88.

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}})}

DC-Gain:

Equation 89.

A_{V M} = \frac{R_{F B B}}{R_{F B B} + R_{F B T}} \times G_{m} \times R_{C O M P}

Compensation zero:

Equation 90.

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

Compensation Pole:

Equation 91.

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

With additional feed-forward capacitor in parallel with R_FBT:

ω_{Z F F} = \frac{1}{R_{F B T} \times C_{C F F}}

Equation 92.

ω_{P F F} = \frac{1}{\frac{1}{\frac{1}{R_{R F B B}} + \frac{1}{R_{R F B T}}} \times C_{F F}}