LM49350RLX/NOPB National Semiconductor, LM49350RLX/NOPB Datasheet - Page 51

• Manufacturer Part Number: LM49350RLX/NOPB
• Description: IC AUDIO SUBSYSTM .8W D 36USMDXT
• Manufacturer: National Semiconductor
• Series: Boomer®r
• Type: Class Dr

Specifications of LM49350RLX/NOPB

• Output Type: 1-Channel (Mono) with Mono and Stereo Headphones
• Max Output Power X Channels @ Load: 2W x 1 @ 4 Ohm; 69mW x 2 @ 32 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: 3D, DAC, Depop, I²C, I²S, Mute, Short-Circuit and Thermal Protection, Shutdown, Volume Control
• Mounting Type: Surface Mount
• Package / Case: 36-MicroSMDxt
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM49350RLX

23.0 Digital Mixer Control Registers
23.1 DIGITAL MIXER
The LM49350’s digital mixer allows for flexible routing of dig-
ital audio signals between both audio ports, DAC, and ADC.
This mixer handles which digital data path (Port1 RX data,
Port2 RX data, or ADC output) is routed to the DAC input. The
digital mixer also selects the appropriate digital data path
(Port1 RX data, Port2 RX data, ADC output, DAC DSP output,
or ADC DSP output) that is used for data transmission on Au-
dio Port 1 and 2. Audio inputs to the digital mixer can be
attenuated down to -18dB to avoid clipping conditions.
The LM49350 includes two separate and independent DSP
blocks, one for the DAC and the other for the ADC. The digital
mixer also allows both DSP blocks to be cascaded together
in either order so that the DSP effects from both blocks can
FIGURE 16. Digital Mixer
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Another key feature of the digital mixer is sample rate con-
version (SRC) between audio ports. This allows simultaneous
operation of the dual audio ports even if each port is operating
at a different sample rate. The LM49350 can be used as an
audio port bridge with SRC capability. The digital mixer allows
either straight pass through between audio ports or, if desired,
DSP effects can be added to the digital audio signal during
audio port bridge operation. The digital mixer automatically
handles stereo I
ports and vice versa.
be combined into the same signal path. For example, the 5
band parametric EQ of each DSP block can be combined to-
gether to form a 10 band parametric EQ for added flexibility.
2
S to mono PCM conversion between audio
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