AD1845 Analog Devices, AD1845 Datasheet - Page 36

• Manufacturer Part Number: AD1845
• Description: Parallel-port 16-Bit Soundport Stereo Codec
• Manufacturer: Analog Devices

COMPATIBILITY WITH CS4231
AD1845
2. The AD1845 requires the input antialiasing filters for the
3. The CS4231 does not require the power pins (V
4. The CS4231 does not provide software programmable
5. The CS4231 does not have the ability to mix the MIC
1. The CS4231 requires a 1000 pF NPO type capacitor on
6. The CS4231 does not contain a Variable Sample Fre-
Pins 26 and 31. The AD1845 requires a 1 F capacitor on
filter Pins 26 and 31. To achieve compatibility with the
AD1845, use pad spacing that will accommodate either
1000 pF NPO capacitors for the CS4231 and the CS4248
or the 1 F capacitors for the AD1845.
ADCs (refer to Figures 25 and 26). The CS4231 can use
the same filters with no degradation in performance. For
compatibility it is suggested that the filters be added.
45, and 54, or the ground pins (GNDD) 25, and 44. It is
suggested that the appropriate power/ground pin connec-
tions be made. This will not affect the performance of the
CS4231.
power-down modes.
input with the DAC output.
quency Generator and cannot change sample rates “on the
fly.” The CS4231 and CS4248 require entering MCE to
change the sample rate. The AD1845 can change the
sample rate without entering MCE. The AD1845’s 50,000
selectable sample rates are not available on the CS4231.
The Variable Sample Frequency Generator reduces clicks
and pops encountered in many game applications.
DD
) 24,
–36–
10. The AD1845 is designed to support “little endian” for-
11. The AD1845 does not include hardware for compressing
7. The CS4231 requires 2 crystal inputs, 24.575 MHz and
8. The CS4231 does not contain the INITD bit.
9. The CS4231 minimum R
16.9344 MHz. The AD1845 requires only 1 input of
24.576 MHz or can be driven from OSC or other exter-
nal clocks.
mum input resistance is 10 k .
mats. The CS4231 supports both “big endian” and “little
endian” formats.
and decompressing ADPCM data. Analog Devices offers
Windows based software applets for using ADPCM for-
mats with the AD1845.
IN
= 20 k . The AD1845 mini-
REV. B