Datasheet

Ccomp =
8 x 10
3
x Rcomp[14]
1
Rcomp = 2.5 x 10
5
x Rfb1[9] x Cout[13] +
Rfb1[9]
Vout[1]
www.ti.com Quick Guide Design Worksheet
Step 11. Ccomp and Rcomp configure the error amplifier gain characteristics to accomplish a stable
overall loop gain. One advantage of current mode control is the ability to close the loop with only two
feedback components. Calculate the value of Rcomp:
(9)
Selected value of Rcomp: Ohms [14]
Calculate the value of Ccomp
(10)
Selected value of Ccomp: Farads [15]
Step 12. Shown in the following table is the Bill of Materials for your design. Transcribe each value [#]
from worksheet above into the following table. Congratulations, you’re done.
Table 1. Bill of Materials
SCH REF PART NUMBER DESCRIPTION VALUE WORK SHEET REF
C1 (Cin) INPUT CAPACITOR [12]
C2 (Cout) OUTPUT CAPACITOR [13]
C3 (CRAMP) RAMP CAPACITOR [8]
C4 (Css) C2012X7R2A103K CAPACITOR, TDK 0.01µ --
C5 (Ccomp) COMPENSATION [15]
CAP
C6 (Cboot) C2012X7R2A223K CAPACITOR, TDK 0.022µ --
C7 (Cbyp) C2012X7R1C474M CAPACITOR, TDK 0.47µ, 16V --
D1 SCHOTTKY DIODE [11]
L1 INDUCTOR [7]
R1 (Rfb1) Feedback RESISTOR [10]
R2 (Rfb2) Feedback RESISTOR [9]
R3 (Rt) TIMING RESISTOR [6]
R4 (Rcomp) COMPENSATION [14]
RESISTOR
U1 REGULATOR, TI [4]
5
SNVA206B–January 2007–Revised April 2013 AN-1563 Quick Start Guide for a 0.5 Amp Buck Regulator Using The
LM5574 and LM25574
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