MAX9791:Windows Vista-Compliant Class D Speaker Amplifiers with DirectDrive Headphone Amplifiers

36% Smaller, 68% More Efficient—Industry's First Class D Vista-Compliant Notebook Audio Subsystem

The MAX9791 combines a stereo 2W Class D power amplifier, a stereo 180mW DirectDrive® headphone amplifier, and a 120mA low-dropout (LDO) linear regulator in a single device. The MAX9792 combines a mono 3W Class D power amplifier, a stereo 180mW DirectDrive headphone amplifier, and a 120mA LDO linear regulator in a single device. The MAX9791/MAX9792 feature Maxim's DirectDrive headphone amplifier architecture that produces a ground-referenced output from a single supply, eliminating the need for large DC-blocking capacitors, saving cost, board space, and component height. High 107dB DC PSRR and low 0.006% THD+N ensure clean, low-distortion amplification of the audio signal. The ground sense feature senses and corrects for the voltage difference between the output jack ground and device signal ground. This feature minimizes headphone amplifier crosstalk by sensing the impedance in the ground return trace and correcting for it at the output jack. This feature also minimizes ground-loop noise when the output socket is used as a line out connection to other grounded equipment (for example, a PC connected to a home hi-fi system). The MAX9791/MAX9792 feature low RF susceptibility, allowing the amplifiers to successfully operate in close proximity to wireless applications. The MAX9791/MAX9792 Class D amplifiers feature Maxim's spread-spectrum modulation and active emissions limiting circuitry. Industry-leading click-and-pop suppression eliminates audible transients during power-up and shutdown cycles. The MAX9791/MAX9792 wake-on-beep feature wakes up the speaker and headphone amplifiers when a qualified beep signal is detected at the BEEP input. For maximum flexibility, separate speaker and headphone amplifier control inputs provide independent shutdown of the speaker and headphone amplifiers. Additionally the LDO can be enabled independently of the audio amplifiers. The MAX9791/MAX9792 feature thermal-overload and output short-circuit protection. The devices are available in 28-pin TQFN packages and are specified over the -40°C to +85°C extended temperature range.

Key Features
  • Windows Vista® Premium Compliant
  • Low EMI Filterless Class D Speaker Amplifiers Pass EN55022B Emissions Limit with 30cm of Speaker Cable
  • 180mW DirectDrive Headphone Amplifier
  • Excellent RF Immunity
  • Integrated 120mA LDO
  • Eliminates Headphone Ground Loop Noise
  • Wake-on-Beep Function
  • Click-and-Pop Suppression
  • Short-Circuit and Thermal-Overload Protection
  • Thermally Efficient, Space-Saving Package
    • 28-Pin TQFN-EP (4mm x 4mm x 0.75mm)
MAX9791, MAX9792: Simplified Block Diagram
MAX9791, MAX9792: Simplified Block Diagram
Applications/Uses
  • Notebook Computers
  • Portable Multimedia Players
  • Tablet PCs
DataSheet
titleDownload file
MAX9791-MAX9792 Data SheetMAX9791-MAX9792.pdf
Parametrics
Part NumberFunctionsClassSpkr. Amp. VCC
(V)
Spkr. Amp. VCC
(V)
Spkr. Amp. ICC
(mA)
Spkr. Amp. POUT
(W)
Spkr. Amp. Half Pwr. THD+N
(%)
Hdph. Amp. VCC
(V)
Hdph. Amp. VCC
(V)
Hdph. Amp. ICC
(mA)
Hdph. Amp. POUT into 32Ω
(mW)
Hdph. Amp. Half Pwr. THD+N
(%)
Package/PinsBudgetary
Price
minmaxtypminmaxtyp@ 1% THD+NSee Notes
MAX9791Mobile Communication Subsystem
Netbook Subsystem
PC Notebook Subsystem
D4.55.5141.70.042.75.50.250.180.006TQFN/28$1.45 @1k
MAX979230.03-5.5TQFN/28
Design kits & evaluation modules
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX9791AETI+ActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791AETI+TActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791BETI+ActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791BETI+TActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791CETI+ActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791CETI+TActiveTQFN,;28 pin;16.8 mm²-40°C to +85°CLead Free
MAX9791-MAX9792.pdf MAX9792
MAX9791-MAX9792.pdf MAX9792