TMS320F28075PZPQ datasheet(51/182 Pages) TI1

51 / 182 page

TMS320F28075

www.ti.com

SPRS902B – OCTOBER 2014 – REVISED OCTOBER 2015

5.7.3.4

Crystal Oscillator

When using a quartz crystal, it may be necessary to include a damping resistor (RD) in the crystal circuit to

prevent over-driving the crystal (drive level can be found in the crystal data sheet). In higher-frequency

applications (10 MHz or greater), RD is generally not required. If a damping resistor is required, RD should

be as small as possible because the size of the resistance affects start-up time (smaller RD = faster start-

up time). It is recommended that the crystal manufacturer characterize the crystal with the application

board.

Table 5-15. Crystal Oscillator Parameters

MIN

MAX

UNIT

CL1, CL2

Load capacitance

Crystal shunt capacitance

Table 5-16. Crystal Equivalent Series Resistance (ESR) Requirements(1)(2)

MAXIMUM ESR (

Ω)

MAXIMUM ESR (

Ω)

CRYSTAL FREQUENCY (MHz)

(CL1 = CL2 = 12 pF)

(CL1 = CL2 = 24 pF)

110

(1)

Crystal shunt capacitance (C0) should be less than or equal to 7 pF.

(2)

ESR = Negative Resistance/3

Table 5-17. Crystal Oscillator Electrical Characteristics

over recommended operating conditions (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

f = 20 MHz

ESR MAX = 50

Start-up time(1)

CL1 = CL2 = 24 pF

C0 = 7 pF

Crystal drive level (DL)

(1)

Start-up time is dependent on the crystal and tank circuit components. It is recommended that the crystal vendor characterize the

application with the chosen crystal.

Specifications

Submit Documentation Feedback

Product Folder Links: TMS320F28075

TMS320F28075PZPQ Datasheet(PDF) 51 Page - Texas Instruments

TMS320F28075PZPQ Datasheet(HTML) 51 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

Datasheet Download

Link URL