- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄166217 > AM79Q021VC (ADVANCED MICRO DEVICES INC) PCM CODEC, PQFP44 PDF資料下載
參數(shù)資料
| 型號： | AM79Q021VC |
| 廠商： | ADVANCED MICRO DEVICES INC |
| 元件分類： | 編解碼器 |
| 英文描述： | PCM CODEC, PQFP44 |
| 封裝： | TQFP-44 |
| 文件頁數(shù)： | 30/64頁 |
| 文件大?。?/td> | 911K |
| 代理商： | AM79Q021VC |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁當(dāng)前第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁
36
Am79Q02/021/031 Data Sheet
Figure 13. Robbed-Bit Frame
Default Filter Coefficients
The QSLAC device contains an internal set of default
coefficients for the programmable filters. These coeffi-
cients were determined to allow reasonable system
performance for initial power-up non-programmed situ-
ations, such as may exist before a system processor
has opportunity to program any coefficients.
The default filter coefficients are calculated assuming
an Am7920 SLIC with 50
protection resistors, a
178 k
transversal impedance (ZT), and a 90.5 k re-
ceive impedance (ZRX). This SLIC has a transmit gain
of 0.5 (GTX) and a current gain of 500 (K1). The trans-
mit relative level is set to +0.28 dBr, and the receive rel-
ative level is set to –4.39 dBr. The equalization filters (X
and R) are not optimized. The balance filter was de-
signed to give acceptable balance into a variety of im-
pedances. The nominal input impedance was set to
815
. If the SLIC circuit differs significantly from this
design, the default filters cannot be used and must be
replaced by programmed coefficients.
To obtain this above-system response, the default filter
coefficients are set to produce these values:
GX gain = +6 dB, GR gain = –8.984 dB
AX gain = 0 dB, AR gain = 0 dB
R filter: H(z) = 1, X filter: H(z) = 1
Z filter: H(z) = 0, B filter H(z) = 0
AISN = cutoff
Notice that these default coefficient values are retained
in a read-only memory area within the QSLAC device,
and those values cannot be read back using any data
commands. When the device is selected to use default
coefficients, it obtains those values directly from the
read-only memory area, where the coefficient read
operations access the programmable random access
data memory only. If an attempt is made to read back
any filter values without those values first being written
with known programmed data, the values read back
are totally random and do not represent the default or
any other values.
COMMAND DESCRIPTION AND FORMATS
Microprocessor Interface Description
A microprocessor can program and control the
QSLAC device using the MPI. Data programmed
previously can be read out for verification.
Commands assign values to the following channel
parameters:
Transmit time slot
Receive time slot
Transmit clock slot
Receive clock slot
Transmit gain
Receive loss
B-filter coefficients
X-filter coefficients
R-filter coefficients
Z-filter coefficients
AISN coefficient
Read/Write SLIC Input/Output
SLIC Input/Output Direction
Select A-law, -law, or linear code
Select Transmit PCM Port A or B or both
Select Receive PCM Port A or B
Programmed/Default B filter
Programmed/Default Z filter
Programmed/Default X filter
Programmed/Default R filter
Programmed/Default GX filter
Programmed/Default GR filter
Enable/disable AX amplifier
Enable/disable AR amplifier
Select test states
Select Active or Inactive (standby) state
Commands are provided to read values from the
following channel monitors:
SLIC status
Transmit PCM data
PCLK
FS
Normal Frame (Not Robbed-Bit)
PCLK
FS
Robbed-Bit Frame
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AM79Q062JC | A/MU-LAW, PCM CODEC, PQCC32 |
| AM80A-048L-050P25 | 1-OUTPUT 125 W DC-DC REG PWR SUPPLY MODULE |
| AM8152BDC | SPECIALTY INTERFACE CIRCUIT, CDIP48 |
| AMB315218 | MOTION SENSOR, XSS |
| AMCY-ED12566/1 | 880 MHz - 915 MHz RF/MICROWAVE DOUBLE BALANCED MIXER |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AM79Q02JC | 制造商:Advanced Micro Devices 功能描述: |
| AM79Q031 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Quad Subscriber Line Audio-Processing Circuit (QSLAC) Devices |
| AM79Q031JC | 制造商:Advanced Micro Devices 功能描述: |
| AM79Q061JC | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Telecommunication IC |
| AM79Q061VC | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Telecommunication IC |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。