February 2009

Rev 1

1/12

12

AN2837

Application note

Positive to negative buck-boost converter

using ST1S03 asynchronous switching regulator

Abstract

The ST1S03 is a 1.5 A, 1.5 MHz adjustable step-down switching regulator housed in a

DFN6 package with internal power switch.

The device is a complete 1.5 A switching regulator with internal compensation that

eliminates the need for additional components. In this document the design of a polarity

inverting converter is discussed.

Figure 1.

C1

C4

C3

C2

R1

R2

L1

D1

V

V

R3

C1

C4

C3

C2

R1

R2

L1

D1

V

V

R3

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