Datasheet

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Feedback Components (R3, R6, C3, C4, C5)
C5 +
1
2 p R8 F
Z2
(28)
R6 +
1
2 p C5 F
P1
(29)
R3 +
A
MID(band)
(
R6 R8
)
R6 ) R8
(30)
C4 +
1
2 p R3 F
Z1
(31)
C3 +
1
2 p R3 F
P2
(32)
0dB
F
Z1
Frequency (Log Scale)
F
Z2
F
P1
F
P2
A
mid−Band
F
SW
TPS40040 , TPS40041
SLUS700D – MARCH 2006 – REVISED DECEMBER 2007
Approximate C5 with the formula:
C5 = 560 pF (closest standard capacitor value to calculated 568 pF) and approximate R6 with the formula:
R6 = 4.75 k Ω (closest standard resistor value to calculated 4.74 k Ω ) Calculate R3 by the formula:
With A
MID_BAND
= 3.84, R6 = 4.75 k Ω and R8 = 20 k Ω , R3 = 14.7 k Ω (closest standard resistor value to calculated
14.7 k Ω ) Calculate C3 and C4 by the equations:
For R3 = 14.7 k Ω , C3 = 47 pF (closest standard value to 45 pF) C4 = 1200 pF (closest standard value to 1.2 nF)
Error Amplifier straight line approximation transfer function looks like Figure 25 .
Figure 25. Error Amplifier Frequency Response Straight Line Approximation
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Product Folder Link(s): TPS40040 TPS40041