PIFE32251B-R68MS datasheet(134/157 Pages) TI1

134 / 157 page

RT1

RT2

RT3

RT4

VCOMP Pin

VREF = 1.25V

100k

TRIPZ Pin

10µA

134

TPS650830

SLVSCF4A – DECEMBER 2014 – REVISED JULY 2016

www.ti.com

Submit Documentation Feedback

Product Folder Links: TPS650830

Application and Implementation

7.2.2.2.3 Selecting the Input Capacitors

Because of the nature of the switching converter and controller with a pulsating input current, a low ESR

input capacitor is required for best input voltage filtering and minimizing the interference with other circuits

caused by high input voltage spikes. For the controller, 12 µF of input capacitance is recommended for

most applications. To achieve the low ESR requirement, a ceramic capacitor is recommended. However,

the voltage rating and DC bias characteristic of ceramic capacitors need to be considered. The input

capacitor can be increased without any limit for better input voltage filtering. Be sure to size the ceramic

capacitor to achieve the recommended input capacitance. A ceramic capacitor placed as close as possible

to the respective VINx and PGNDx pins of the IC is recommended.

The preferred capacitors for the controllers are two muRata GRM21BR61E106MA73: 10 μF, 0805, 25 V,

±20% or similar.

7.2.2.3

LDO Design Procedure

The LDO must handle the fast load transients from the DDR memory for termination. Therefore, it is

important to maintain a high amount of capacitance with low ESR on the LDO outputs and inputs. Ceramic

capacitors are ideal for this. Below is the recommended capacitors.

The preferred output capacitor for the LDO is muRata GRM188R60J476M: 47 μF, 0603, 6.3 V, ±20% or

similar.

The preferred input capacitor for the LDO is muRata GRM155R60J106ME44: 10 μF, 0402, 6.3 V, ±20% or

similar.

7.2.2.4

Board Temperature Monitoring Design Procedure

Board temperature monitoring requires only 1 thermistor if only 1 sense point is desired. It can be scaled

by adding as many thermistors as sense points desired. Simply connect a PTC thermistor that has an

exponential coefficient curve from the VCOMP pin to GND and a pull up to desired voltage source on the

TRIPZ pin. Place thermistor where desired. If multiple sense points are desired string the thermistors

together in a series connection while placing the thermistors where desired.

Figure 7-5. Board Temperature Monitoring Circuit Example

PIFE32251B-R68MS 데이터시트(PDF) 134 Page - Texas Instruments

PIFE32251B-R68MS 데이터시트(HTML) 134 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

데이터시트 다운로드

링크 URL