MAX9776ETJ+ Maxim Integrated Products, MAX9776ETJ+ Datasheet - Page 20

• Manufacturer Part Number: MAX9776ETJ+
• Description: IC AMP AUDIO PWR 1.5W D 32TQFN
• Manufacturer: Maxim Integrated Products
• Series: DirectDrive™r
• Type: Class Dr

Specifications of MAX9776ETJ+

• Output Type: 1-Channel (Mono) with Stereo Headphones
• Max Output Power X Channels @ Load: 1.5W x 1 @ 4 Ohm; 60mW x 2 @ 16 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: Depop, Differential Inputs, I²C, Mute, Short-Circuit and Thermal Protection, Shutdown, Volume Control
• Mounting Type: Surface Mount
• Package / Case: 32-TQFN Exposed Pad
• Product: Class-D
• Output Power: 1.5 W
• Common Mode Rejection Ratio (min): 45 dB
• Thd Plus Noise: 0.04 %
• Operating Supply Voltage: 2.7 V to 5.5 V
• Supply Current: 9.5 mA
• Maximum Power Dissipation: 1360 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.7 V
• Amplifier Class: D
• No. Of Channels: 3
• Supply Voltage Range: 2.7V To 5.5V
• Load Impedance: 4ohm
• Operating Temperature Range: -40°C To +85°C
• Amplifier Case Style: TQFN
• Rohs Compliant: Yes
• For Use With: MAX9776EVKIT+ - EVALUATION KIT FOR MAX9776
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The MAX9775/MAX9776 feature a fixed-frequency
modulation mode with a 1.1MHz switching frequency,
set through the I
cy modulation mode, the frequency spectrum of the
Class D output consists of the fundamental switching
frequency and its associated harmonics (see the
Wideband Output Spectrum Fixed-Frequency Mode
graph in the Typical Operating Characteristics ).
The MAX9775/MAX9776 feature a unique spread-spec-
trum modulation that flattens the wideband spectral com-
ponents. Proprietary techniques ensure that the
2 x 1.5W, Stereo Class D Audio Subsystem
with DirectDrive Headphone Amplifier
Figure 2. Output with an Input Signal Applied (Spread-Spectrum Modulation Mode)
20
______________________________________________________________________________________
V
V
V
OUT+
IN+
IN-
- V
OUT-
OUT+
OUT-
2
C interface (Table 2). In fixed-frequen-
t
ON(MIN)
Spread-Spectrum Modulation
Fixed-Frequency Modulation
Operating Modes
t
SW
t
SW
cycle-to-cycle variation of the switching period does not
degrade audio reproduction or efficiency (see the
Typical Operating Characteristics ). Select spread-spec-
trum modulation mode through the I
2). In spread-spectrum modulation mode, the switching
frequency varies randomly by ±30kHz around the center
frequency (1.16MHz). The modulation scheme remains
the same, but the period of the sawtooth waveform
changes from cycle to cycle (Figure 2). Instead of a
large amount of spectral energy present at multiples of
the switching frequency, the energy is now spread over
a bandwidth that increases with frequency. Above a few
megahertz, the wideband spectrum looks like white
noise for EMI purposes (see Figure 3).
t
SW
t
SW
2
C interface (Table