参数资料
型号: AD73322LARUZ-REEL
厂商: Analog Devices Inc
文件页数: 21/43页
文件大小: 0K
描述: IC PROCESSOR FRONTEND DL 28TSSOP
标准包装: 2,500
位数: 16
通道数: 4
功率(瓦特): 73mW
电压 - 电源,模拟: 2.7 V ~ 5.5 V
电压 - 电源,数字: 2.7 V ~ 5.5 V
封装/外壳: 28-TSSOP(0.173",4.40mm 宽)
供应商设备封装: 28-TSSOP
包装: 带卷 (TR)
AD73322
–28–
REV. B
The device features an on-chip master clock divider circuit that
allows the sample rate to be reduced as the sampling rate of the
sigma-delta converter is proportional to the output of the MCLK
Divider (whose default state is divide by 1).
The decimator’s frequency response (Sinc3) gives some pass-
band attenuation (up to FS/2) which continues to roll off above
the Nyquist frequency. If it is required to implement a digital
filter to create a sharper cutoff characteristic, it may be prudent
to use an initial sample rate of greater than twice the Nyquist
rate in order to avoid aliasing due to the smooth roll-off of the
Sinc3 filter response.
In the case of voiceband processing where 4 kHz represents the
Nyquist frequency, if the signal to be measured were externally
bandlimited then an 8 kHz sampling rate would suffice. How-
ever if it is required to limit the bandwidth using a digital filter,
then it may be more appropriate to use an initial sampling rate
of 16 kHz and to process this sample stream with a filtering and
decimating algorithm to achieve a 4 kHz bandlimited signal at
an 8 kHz rate. Figure 23 details the initial 16 kHz sampled tone.
FREQUENCY – Hz
0
1000
0
–20
dB
–40
–60
–80
–100
–120
2000
3000
4000
5000
6000
7000
8000
–140
Figure 23. FFT (ADC 16 kHz Direct Sampling)
Figure 24 details the spectrum of the final 8 kHz sampled fil-
tered tone.
FREQUENCY – Hz
0
500
0
–20
dB
–40
–60
–80
–100
–120
1000
1500
2000
2500
3000
3500
4000
–140
Figure 24. FFT (ADC 8 kHz Filtered and Decimated from
16 kHz)
Encoder Group Delay
When programmed for high sampling rates, the AD73322 offers
a very low level of group delay, which is given by the following
relationship:
Group Delay (Decimator) = Order
× ((M – 1)/2) × T
DEC
where:
Order is the order of the decimator (= 3),
M is the decimation factor (= 32 @ 64 kHz, = 64 @ 32 kHz,
= 128 @ 16 kHz , = 256 @ 8 kHz) and
TDEC is the decimation sample interval (= 1/2.048e6) (based
on DMCLK = 16.384 MHz) => Group Delay (Decimator @
64 kHz) = 3
× (32 – 1)/2 × (1/2.048e6) = 22.7 s
If final filtering is implemented in the DSP, the final filter’s
group delay must be taken into account when calculating overall
group delay.
Decoder Section
The decoder section updates (samples) at the same rate as the
encoder section. This rate is programmable as 64 kHz, 32 kHz,
16 kHz or 8 kHz (from a 16.384 MHz MCLK). The decoder
section represents a reverse of the process that was described in
the encoder section. In the case of the decoder section, signals
are applied in the form of samples at an initial low rate. This
sample rate is then increased to the final digital sigma-delta
modulator rate of DMCLK/8 by interpolating new samples
between the original samples. The interpolating filter also has the
action of canceling images due to the interpolation process using
spectral nulls that exist at integer multiples of the initial sam-
pling rate. Figure 25 shows the spectral response of the decoder
section sampling at 64 kHz. Again, its sigma-delta modulator
shapes the noise so it is reduced in the voice bandwidth dc–
4 kHz. For improved voiceband SNR, the user can implement
an initial anti-imaging filter, preceded by 8 kHz to 64 kHz inter-
polation, in the DSP.
FREQUENCY – Hz
0
0.5
0
dB
–20
1.0
1.5
2.0
2.5
3.0
3.5
–100
–10
–30
–40
–50
–60
–70
–80
–90
104
Figure 25. FFT (DAC 64 kHz Sampling)
相关PDF资料
PDF描述
AD73322LYRZ IC ANALOG FRONT END DUAL 28-SOIC
AD73360ARZ IC PROCESSOR FRONTEND 6CH 28SOIC
AD7352YRUZ-500RL7 IC ADC DUAL 12BIT 3MSPS 16TSSOP
AD7356YRUZ-500RL7 IC ADC DUAL 12BIT 5MSPS 16TSSOP
AD7357YRUZ IC ADC DUAL14BIT 4.2MSPS 16TSSOP
相关代理商/技术参数
参数描述
AD73322LARZ 功能描述:IC ANALOG FRONT END DUAL 28-SOIC RoHS:是 类别:集成电路 (IC) >> 数据采集 - 模拟前端 (AFE) 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 位数:- 通道数:2 功率(瓦特):- 电压 - 电源,模拟:3 V ~ 3.6 V 电压 - 电源,数字:3 V ~ 3.6 V 封装/外壳:32-VFQFN 裸露焊盘 供应商设备封装:32-QFN(5x5) 包装:带卷 (TR)
AD73322LARZ-REEL 制造商:Analog Devices 功能描述:DUAL-CHANNEL, 3 V FRONT-END PROCESSOR FOR GENERAL PURPOSE - Tape and Reel
AD73322LAST 制造商:Rochester Electronics LLC 功能描述:SPEECH AND TELEPHONY CODEC I.C. - Tape and Reel 制造商:Analog Devices 功能描述:
AD73322LAST-REEL 制造商:Analog Devices 功能描述:Audio Codec 2ADC / 2DAC 16-Bit 44-Pin LQFP T/R 制造商:Rochester Electronics LLC 功能描述:SPEECH AND TELEPHONY CODEC I.C. - Tape and Reel
AD73322LASTZ 制造商:Analog Devices 功能描述: 制造商:Rochester Electronics LLC 功能描述: