L5987 View Datasheet(PDF) - STMicroelectronics

Part Name

Description

MFG CO.

L5987

3 A step-down switching regulator

STMicroelectronics 

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L5987

Application information

4. Then calculate C3 in order to place the second pole at four times the system bandwidth

(BW):

Equation 30

C5 = 2------------R-----4-------C----C4----4---4--------B----W--------–----1--

For example: with VOUT = 3.3 V, VIN = 12 V, IO = 3 A, L = 10 H, COUT = 330 F,

ESR = 35 m the type II compensation network is:

R1 = 1.5k R2 = 330 R4 = 10k C4 = 47nF C5 = 82pF

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