L5983 datasheet(20/37 Pages) STMICROELECTRONICS

Part #	L5983

Description	1.5A step-down switching regulator

PDF	37 Pages

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Manufacturer	STMICROELECTRONICS [STMicroelectronics]

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20 / 37 page

Application informations

L5983

20/37

In Figure 10 the type III compensation network is shown. This network introduces two zeros

(fZ1, fZ2) and three poles (fP0, fP1, fP2). They expression are:

Equation 16

Equation 17

Figure 10.

Type III compensation network

In Figure 11 the Bode diagram of the PWM and LC filter transfer function (GPW0 · GLC(f))

and the open loop gain (GLOOP(f)=GPW0 · GLC(f) · GTYPEIII(f)) are drawn.

Figure 11.

Open loop gain: module Bode diagram

π C

()

⋅⋅

------------------------------------------------

π R

⋅⋅

------------------------------

π R

⋅⋅

------------------------------

π R

⋅

--------------------

⋅⋅

--------------------------------------------

L5983 Datasheet(PDF) 20 Page - STMicroelectronics