IDT821034DN IDT, Integrated Device Technology Inc, IDT821034DN Datasheet - Page 8

• Manufacturer Part Number: IDT821034DN
• Description: IC PCM CODEC QUAD MPI 52-PQFP
• Manufacturer: IDT, Integrated Device Technology Inc
• Type: PCM Codec/Filterr

Specifications of IDT821034DN

• Data Interface: PCM Audio Interface
• Number Of Adcs / Dacs: 4 / 4
• Sigma Delta: No
• Voltage - Supply, Analog: 4.75 V ~ 5.25 V
• Voltage - Supply, Digital: 4.75 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 52-MQFP, 52-PQFP
• Single Supply Voltage (typ): 5V
• Single Supply Voltage (min): 4.75V
• Single Supply Voltage (max): 5.25V
• Package Type: PQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 821034DN

APPLICATION NOTE
a typical system with telephony line interface.
signaling channel, which can simplify the circuit design of the control
interface. In addition, the dynamic time slot assignment of IDT821034
reduces the hardware requirement for PCM interface. The device also
supports 8.192 Mbps PCM data rate, which can increase the time slot
density up to 128.
over -55 dBm0 to +3 dBm0 range with a specific gain setting (0 dB for both
transmit path and receive path). Since there is a finite noise floor associated
with the quantization effect of both data converters and digital filter
coefficients, the overall signal to total distortion ratio of each path is a function
of the gain setting. In system design, attention should be paid to the gain
setting for the best signal to total distortion performance.
by both SLIC and CODEC. In a system design using IDT821034, the
SLIC gain should be taken into account to optimize the SNR. In the transmit
path of IDT821034, there are two resistors (R1 and R3 in Figure 5)
which enable the analog gain to be adjusted around 0 dB. Further gain
adjustment can be obtained by programming the DSP filters. Since this
adjustment is close to 0 dB, the SNR remains at the optimum value. In
the receive path of IDT821034, analog gain adjustment is not available.
Thus, the adjustment of CODEC gain will be performed only by
programming the DSP filters. In this way, the SLIC gain should be such
IDT821034 QUAD PCM CODEC WITH PROGRAMMABLE GAIN
The IDT821034 is mainly used in line card application. Figure 5 shows
The IDT821034 offers not only encoding/decoding function, but also a
Signal to total distortion ratio (both STD
Generally, a channel gain of a line-card system is contributed
Bit
Bit
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
Register Indicator
--
--
O_4 Data
O_3 Data
O_2 Data
I/O_1 Data
I/O _0 Data
I/On_0 Image
I/On_1 Image
On_2 Image
On_3 Image
On_4 Image
I/O1_0 Image
I/O2_0 Image
I/O3_0 Image
Name
Name
X
and STD
Table 4. Definition of SLIC Control Register
Table 5. Definition of SLIC Status Register
R
) are guaranteed
Always ‘0’
Reserved, always ‘0’
Reserved, always ‘0’
Output data on O_4 pin of the selected channel
Output data on O_3 pin of the selected channel
Output data on O_2 pin of the selected channel
Output data on I/O_1 pin (if defined as an output) of the selected channel
Output data on I/O_0 pin (if defined as an output) of the selected channel
Mapped to I/On_0 pin of the selected channel n
Mapped to I/On_1 pin of the selected channel n
Mapped to On_2 pin of the selected channel n
Mapped to On_3 pin of the selected channel n
Mapped to On_4 pin of the selected channel n
Always mapped to the I/O1_0 pin
Always mapped to the I/O2_0 pin
Always mapped to the I/O3_0 pin
8
that the DSP gain is closest to 0 dB. This will maximize the achievable
SNR in the overall system. For example, if the design target for receive
path gain is -3.5 dB and -7 dB for local and long distance calls
respectively, the recommended solution is to set SLIC gain at -3.5 dB.
As a result, the gain of CODEC, which is adjusted by programming DSP
coefficients, will be 0 dB and -3.5 dB.
Description
Description
INDUSTRIAL TEMPERATURE RANGE