PIFE32251B-R68MS datasheet(130/157 Pages) TI1

130 / 157 page

+.I=T = +KQPI=T +

J:8+0 F 8176; × 8176

2 ×

8+0 × B59 × . K

130

TPS650830

SLVSCF4A – DECEMBER 2014 – REVISED JULY 2016

www.ti.com

Submit Documentation Feedback

Product Folder Links: TPS650830

Application and Implementation

With the chosen inductance value, the peak current for the inductor in steady state operation, ILmax, can be

calculated using the equation below. The rated saturation current of the inductor must be higher than the

ILmax current.

(2)

Following these equations the preferred inductor selected for the controllers are listed below in Table 7-1.

Table 7-1. Recommended Inductors

MANUFACTURER

PART NUMBER

VALUE

SIZE

HEIGHT

Cyntec

PIME031B

0.47 µH - 1 µH

3.3 mm x 3.7 mm

1.2 mm

Cyntec

PIMB041B

0.33 µH - 2.2 µH

4.45 mm x 4.75 mm

1.2 mm

Cyntec

PIMB051B

1 µH - 3.3 µH

5.4 mm x 5.75 mm

1.2 mm

Cyntec

PIME051E

0.33 µH - 4.7 µH

5.4 mm x 5.75 mm

1.5 mm

Cyntec

PIMB051H

0.47 µH - 4.7 µH

5.4 mm x 5.75 mm

1.8 mm

Cyntec

PIME061B

0.56 µH - 3.3 µH

6.8 mm x 7.3 mm

1.2 mm

Cyntec

PIME061E

0.33 µH - 4.7 µH

6.8 mm x 7.3 mm

1.5 mm

Cyntec

PIMB061H

0.1 µH - 4.7 µH

6.8 mm x 7.3 mm

1.8 mm

7.2.2.1.2 Selecting the Output Capacitors

Ceramic capacitors with low ESR values provide the lowest output voltage ripple and are recommended.

The output capacitor requires either an X7R or X5R dielectric. Y5V and Z5U dielectric capacitors, aside

from their wide variation in capacitance over temperature, become resistive at high frequencies.

At light load currents, the converter operates in Power Save Mode and the output voltage ripple is

dependent on the output capacitor value and the PFM peak inductor current. Higher output capacitor

values minimize the voltage ripple in PFM Mode. In order to achieve specified regulation performance and

low output voltage ripple, the DC-bias characteristic of ceramic capacitors must be considered. The

effective capacitance of ceramic capacitors drops with increasing DC bias voltage.

For the output capacitors of the DCDC controller the use of a small ceramic capacitors placed as close as

possible to the inductor and the respective PGND pins of the IC is recommended. This solution typically,

provides the smallest and lowest cost solution available for DCAP2 controllers.

7.2.2.1.3 Selecting the FETs

This controller is designed to drive NMOS FETs. Typically, the lower RDSon for the high and low side FETs

the better but, be sure to size the FETs, inductor and output capacitors appropriately as the RDSon for the

low side FET decreases, the minimum current limit increases. The Texas Instruments CSD87381P is

recommended for the controllers.

PIFE32251B-R68MS Scheda tecnica(PDF) 130 Page - Texas Instruments

PIFE32251B-R68MS Scheda tecnica(HTML) 130 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Scheda tecnica Scarica

Link URL