AD1849K Analog Devices, AD1849K Datasheet - Page 10

• Manufacturer Part Number: AD1849K
• Description: Serial-Port 16-Bit SoundPort Stereo Codec
• Manufacturer: Analog Devices

AD1849K
The loopback modes are shown graphically in Figure 3.
FUNCTIONAL
DISCONNECTED
FUNCTIONAL
LINE, MIC
LINE, MIC
OUTPUT
OUTPUT
INPUT
LINE 0,
LINE 0
LINE 1
LINE 1
INPUT
Figure 3. AD1849K Loopback Modes
AD1849K Analog Loopback D-A-D
AD1849K Digital Loopback D-D
MUTE
GAIN
GAIN
MUTE
AD1849K
AD1849K
0
1
A/D
D/A
A/D
D/A
MONITOR
MONITOR
DISABLE
µ/A-LAW
ENCODE
µ/A-LAW
DECODE
DECODE
µ/A-LAW
ENCODE
µ/A-LAW
SDRX
SDTX
SDTX
SDRX
–10–
Clocks and Sample Rates
The AD1849K can operate from external crystals, from a 256
F
factor, or from the serial port’s bit clock (at 256
under software control. Two crystal inputs are provided to
generate a wide range of sample rates. The oscillators for these
crystals are on the AD1849K, as is a multiplexer for selecting
between them. They can be overdriven with external clocks by
the user, if so desired. The recommended crystal frequencies are
16.9344 MHz and 24.576 MHz. From them the following sample
rates can be internally generated: 5.5125, 6.615, 8, 9.6, 11.025,
16, 18.9, 22.05, 27.42857, 32, 33.075, 37.8, 44.1, 48 kHz.
Regardless of clock input source, a clock output of 256 F
generated (with some skew). If an external input clock or the
serial port’s bit clocks are selected to drive the AD1849K’s
internal operation, they should be low jitter clocks. If no
external clock will be used, Analog Devices recommends tying
the clock input pin (CLKIN) to ground. If either external
crystal is not used, Analog Devices recommends tying its input
(CIN1 and/or CIN2) to ground.
S
input clock, from an input clock with a programmable divide
F
S
), selected
REV. 0
S
is