max97002 Maxim Integrated Products, Inc., max97002 Datasheet - Page 20

• Manufacturer Part Number: max97002
• Description: Audio Subsystem With Mono Class D Speaker And Class H Headphone Amplifiers
• Manufacturer: Maxim Integrated Products, Inc.

Audio Subsystem with Mono Class D
Speaker and Class H Headphone Amplifiers
Traditional Class D amplifiers require the use of exter-
nal LC filters or shielding in order to meet EN55022B
electromagnetic-interference (EMI) regulation stan-
dards. Maxim’s patented active emissions limiting edge-
rate control circuitry and spread-spectrum modulation
reduces EMI emissions, while maintaining up to 87% effi-
ciency. Maxim’s patented spread-spectrum modulation
Figure 4. EMI with 15cm of Speaker Cable
20
Ultra-Low EMI Filterless Output Stage
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-10
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FREQUENCY (MHz)
FREQUENCY (MHz)
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mode flattens wideband spectral components, while
proprietary techniques ensure that the cycle-to-cycle
variation of the switching period does not degrade audio
reproduction or efficiency. The MAX97002’s spread-
spectrum modulator randomly varies the switching
frequency by Q20kHz around the center frequency
(250kHz). Above 10MHz, the wideband spectrum looks
like noise for EMI purposes (see Figure 4).
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