JAJSH60 データシート

JAJSH60A april 2019 – december 2020 UC1825B-SP

PRODUCTION DATA

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）

HKT|16
- MCDF014A
KGD|0

サーマルパッド・メカニカル・データ

発注情報

8.2.1.7 Compensation

Type IIB compensation was picked for the topology, adding a pole and a zero to the frequency response. The location of where the pole and zero should be placed will depend on the desired crossover frequency and the ESR zero of the output capacitors. The zero in compensation should be placed at least a decade before the crossover frequency for the maximum phase boost. Note that compensation values were picked with a crossover frequency of 5 kHz in mind for this design. The pole from the compensation should be placed at the zero created by the ESR of the output capacitor.

Equation 49.

f_{z E S R} = \frac{1}{2 π \times C_{o u t} \times E S R} = \frac{1}{2 π \times 1146 μ F \times 0.009 Ω} = 15.43 k H z

Equation 50.

f_{p C O M P} = \frac{1}{2 π \times R_{C O M P} \times C_{H F}} = \frac{1}{2 π \times 4.75 k Ω \times 2200 p F} = 15.23 k H z

Equation 51.

f_{z C O M P} = \frac{1}{2 π \times R_{C O M P} \times C_{C O M P}} = \frac{1}{2 π \times 4.75 k Ω \times 0.12 μ F} = 279 H z

The zero from compensation was placed well before the 500-Hz mark which is appropriate. The pole from compensation was optimized while the circuit was tested and thus it was found that placing the pole a little bit earlier smoothed out the frequency response.