AD1938YSTZ Analog Devices Inc, AD1938YSTZ Datasheet - Page 29

• Manufacturer Part Number: AD1938YSTZ
• Description: IC CODEC 24BIT 4ADC/8DAC 48LQFP
• Manufacturer: Analog Devices Inc
• Type: General Purposer

Specifications of AD1938YSTZ

• Data Interface: Serial
• Resolution (bits): 24 b
• Number Of Adcs / Dacs: 4 / 8
• Sigma Delta: Yes
• S/n Ratio, Adcs / Dacs (db) Typ: 94 / 94
• Dynamic Range, Adcs / Dacs (db) Typ: 105 / 106
• Voltage - Supply, Analog: 3 V ~ 3.6 V
• Voltage - Supply, Digital: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Audio Codec Type: Audio
• No. Of Adcs: 4
• No. Of Dacs: 8
• No. Of Input Channels: 4
• No. Of Output Channels: 8
• Adc / Dac Resolution: 24bit
• Adcs / Dacs Signal To Noise Ratio: 108dB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ADDITIONAL MODES
The AD1938 offers several additional modes for board level
design enhancements. To reduce the EMI in board level design,
serial data can be transmitted without an explicit BCLK. See
Figure 27 for an example of a DAC TDM data transmission
mode that does not require high speed DBCLK. This configu-
ration is applicable when the AD1938 master clock is generated
by the PLL with the DLRCLK as the PLL reference frequency.
TDM-DSDATAx
DSDATAx
DLRCLK
INTERNAL
INTERNAL
DSDATAx
DBCLK
DLRCLK
DLRCLK
DBCLK
DBCLK
(Applicable Only If PLL Locks to DLRCLK. This Mode Is Also Available in the ADC Serial Data Port.)
MSB
(Applicable in Stereo and TDM, Useful for High Frequency TDM Transmission.
Figure 27. Serial DAC Data Transmission in TDM Format Without DBCLK
32 BITS
Figure 28. I
This Mode Is Also Available in the ADC Serial Data Port.)
DATA MUST BE VALID
AT THIS BCLK EDGE
2
S Pipeline Mode in DAC Serial Data Transmission
Rev. C | Page 29 of 32
To relax the requirement for the setup time of the AD1938 in
cases of high speed TDM data transmission, the AD1938 can
latch in the data using the falling edge of DBCLK. This effectively
dedicates the entire BCLK period to the setup time. This mode
is useful in cases where the source has a large delay time in the
serial data driver. Figure 28 shows this pipeline mode of data
transmission.
Both the BLCK-less and pipeline modes are available on the
ADC serial data port.
AD1938