link to page 10 link to page 10 AD8392AData SheetMULTITONE POWER RATIO0 The DMT signal used in ADSL/ADSL2+ systems carries data in –10 discrete tones or bins, which appear in the frequency domain in –20 evenly spaced 4.3125 kHz intervals. In applications using this –30 type of waveform, multitone power ratio (MTPR) is a commonly –40 used measure of linearity. MTPR is defined as the measured Bm)–50 difference from the peak of one tone that is loaded with data to (d–60 the peak of an adjacent tone that is intentional y left empty. Figure 19 and Figure 20 show the AD8392A MTPR for a 5.5 –70 crest factor waveform for empty bins in the ADSL and extended –80 ADSL2+ bandwidths. –90 044 –100CENTER 1.9664kHzSPAN 10kHz 06477- 0 Figure 20. MTPR at 1.966 MHz –10–20–30–40Bm)–50(d–60–70–80–90 043 –100CENTER 646.9kHzSPAN 10kHz 06477- Figure 19. MTPR at 647 kHz Rev. A | Page 10 of 12 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION PIN CONFIGURATIONS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE Maximum Power Dissipation ESD CAUTION TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION APPLICATIONS SUPPLIES, GROUNDING, AND LAYOUT POWER MANAGEMENT THERMAL CONSIDERATIONS TYPICAL ADSL/ADSL2+ APPLICATION MULTITONE POWER RATIO OUTLINE DIMENSIONS ORDERING GUIDE NOTES