PTH04T240W Type C Capacitors

9

8

20

10

30

7

6

5

4

3

C − Capacitance −

µF

Without TurboTrans

With TurboTrans

C − Capacitance −

µF

9

8

20

10

30

7

6

5

4

3

Without TurboTrans

With TurboTrans

R

TT +

40

1 * CO 1100

C

O

220 * 1

(kW)

(4)

PTH04T240W, PTH04T241W

www.ti.com ...................................................................................................................................................... SLTS276D – OCTOBER 2006 – REVISED JULY 2009

5-V Input

3.3-V Input

Figure 14. Capacitor Type C,

Figure 15. Capacitor Type C,

5000 < C(

µF)×ESR(mΩ) ≤ 10,000

5000 < C(

µF)×ESR(mΩ) ≤ 10,000

(e.g. OS-CON)

(e.g. OS-CON)

Table 6. Type C TurboTrans CO Values and Required RTT Selection Table

Transient Voltage Deviation (mV)

5-V Input

3.3-V Input

25% load step

50% load step

75% load step

CO

RTT

CO

RTT

(2.5 A)

(5 A)

(7.5 A)

Minimum

Required

Minimum

Required

Required Output

TurboTrans

Required Output

TurboTrans

Capacitance (

µF)

Resistor (k

Ω)

Capacitance (

µF)

Resistor (k

Ω)

75

150

225

220

open

220

open

60

120

180

270

137

290

95.3

50

100

150

350

49.9

360

42.2

40

80

120

460

21.5

480

19.1

30

60

90

680

7.32

680

7.32

25

50

75

860

3.09

860

3.09

20

40

60

1150

short

1200

short

15

30

45

2750

short

3000

short

10

20

30

9300

short

above maximum

N/A

RTT Resistor Selection

The TurboTrans resistor value, RTT can be determined from the TurboTrans programming, see Equation 4.

Where CO is the total output capacitance in µF. CO values greater than or equal to 1100 µF require RTT to be a

short, 0

Ω. (RTT results in a negative value when CO > 1100µF).

To ensure stability, the value of RTT must be calculated using the minimum required output capacitance

determined from the capacitor transient response charts above.

Copyright © 2006–2009, Texas Instruments Incorporated

Submit Documentation Feedback

21

Product Folder Link(s): PTH04T240W PTH04T241W