Datasheet
C-Capacitance- Fm
Transient-mV/A
400
500
600
700
800
900
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
20
10
9
8
7
6
5
4
2
3
1
WithTurboTrans
WithoutTurboTrans
V =12V
I
C-Capacitance- Fm
Transient-mV/A
400
500
600
700
800
900
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
20
10
9
8
7
6
5
4
2
3
1
WithTurboTrans
V =8V
I
WithoutTurboTrans
R
TT
Resistor Selection
R =40
TT
´
kW
1-(C /2350)
O
5x(C /2350)-1
O
(1)
PTH08T210W
SLTS262I – OCTOBER 2005 – REVISED MARCH 2009 ...................................................................................................................................................
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Type A Capacitor Type A Capacitor
12 V Input 8 V Input
Figure 11. Cap Type A, 100 ≤ C( µ F)xESR(m Ω ) ≤ 1000 Figure 12. Cap Type A, 100 ≤ C( µ F)xESR(m Ω ) ≤ 1000
(e.g. Ceramic) (e.g. Ceramic)
Table 2. Type A TurboTrans C
O
Values & Required R
TT
Selection Table
Transient Voltage Deviation (mV) 12 V Input 8 V Input
25% 50% 75% C
O
R
TT
C
O
R
TT
Load Step Load Step Load Step Minimum Required Required Minimum Required Required
(7.5 A) (15 A) (22.5 A) Output TurboTrans Output TurboTrans
Capacitance Resistor ( Ω ) Capacitance Resistor ( Ω )
( µ F) ( µ F)
130 260 390 470 open 580 127 k
120 240 360 520 294 k 640 80.6 k
110 220 330 580 127 k 710 54.9 k
100 200 300 650 76.8 k 800 37.4 k
90 180 270 740 47.5 k 900 26.7 k
80 160 240 850 31.6 k 1050 17.8 k
70 140 210 1000 20.5 k 1250 11.3 k
60 120 180 1200 12.7 k 1500 6.65 k
50 100 150 1500 6.65 k 1900 2.55 k
40 80 120 2000 1.82 k 2600 0
30 60 90 4000 0 7800 0
The TurboTrans resistor value, R
TT
can be determined from the TurboTrans programming equation, see
Equation 1 .
Where C
O
is the total output capacitance in µ F. C
O
values greater than or equal to 2350 µ F require R
TT
to be a
short, 0 Ω . (Equation 1 will result in a negative value for R
TT
when C
O
≥ 2350 µ F.)
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