參數(shù)資料
型號(hào): AD9957BSVZREEL13
廠商: ANALOG DEVICES INC
元件分類: 通信及網(wǎng)絡(luò)
英文描述: 1 GSPS Quadrature Digital Upconverter w/18-Bit IQ Data Path and 14-Bit DAC
中文描述: SPECIALTY TELECOM CIRCUIT, QFP48
封裝: PLASTIC, MS-026-AED-HD, TQFP-48
文件頁數(shù): 13/38頁
文件大小: 602K
代理商: AD9957BSVZREEL13
PRELIMINARY TECHNICAL DATA
AD9957
Rev. PrF | Page 13 of 38
delivered to the input of the AD9957 may be formatted as either
twos-complement or unsigned binary (see the
Data Format
bit
in the register map). Furthermore, in BFI mode, the order of
the bit sequence can be set to either "MSB First" or "LSB First"
(via the
BlackFin Bit Order
bit in the register map).
Inverse CCI Filter
The inverse CCI (cascaded comb integrator) filter precompen-
sates the data to offset the slight attenuation gradient imposed
by the CCI filter (see the Programmable (2× to 63×) CCI Inter-
polating filter section). Data entering the first half-band filter
occupies a maximum band width of one-half f
IQ
as defined by
Nyquist (where f
IQ
is the sample rate at the input of the first
half-band filter). This is shown graphically in Figure 7.
If the CCI filter is employed, the inband attenuation gradient
could pose a problem for those applications requiring an ex-
tremely flat pass band. For example, if the spectrum of the data
as supplied to the AD9957 occupies a significant portion of the
one-half f
DATA
region, the higher frequencies of the data spec-
trum receives slightly more attenuation than the lower frequen-
cies (the worst-case overall droop from f=0 to f
DATA
is < 0.8
dB). The Inverse CCI filter has a response characteristic that is
the inverse of the CCI filter response over the f
IQ
region.
Figure 7. CCI Filter Response
The product of the two responses yields in an extremely flat
pass band (±0.05 dB over the base band Nyquist band width),
thereby eliminating the inband attenuation gradient introduced
by the CCI filter. The cost is a slight attenuation of the input
signal of approximately 0.5 dB for a CCI interpolation rate of 2
and 0.8 dB for interpolation rates of 3 to 63.
The Inverse CCI filter can be bypassed using the appropriate bit
in the register map. Even if it is enabled, it is automatically by-
passed if the CCI interpolation rate is 1×. When the Inverse
CCI filter is bypassed, power to the stage is turned off to reduce
power consumption.
Fixed interpolator (4x)
This block is a fixed 4× rate interpolator. It is implemented as a
cascade of two half-band filters. Together, the two half-band
filters provide a factor of four increase in the sampling rate,
while preserving the spectrum of the base band signal applied at
the input. Both half-band filters are linear phase filters, so that
virtually no phase distortion is introduced within the pass band
of the filters. Their combined insertion loss is 0.01 dB, thus
preserving the relative amplitude of the input signal.
The half-band filters are designed so that their composite per-
formance yields a usable pass band of 40% of the input sample
rate (0.2 on the frequency scale below). Within that pass band,
the ripple does not exceed 0.002 dB. The stop band extends
from 60% to 200% of the input sample rate (0.3 to 1.0 on the
frequency scale) and offers a minimum of 85 dB attenuation.
Figure 8 and Figure 9 show the composite response of the two
half-band filters.
FREQUENCY
0
0.2
0.4
10
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–120
–130
–140
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
0.3
0.2
–85
S
0
Figure 8. Half-Band 1 and 2 Frequency Response; Frequency
Relative to HB1 Output Sample Rate
0
0
0.05
0.10
0.15
0.20
0.25
0.010
0.008
0.006
0.004
0.002
–0.002
–0.004
–0.006
–0.008
–0.010
RELATIVE FREQUENCY (HB1 OUTPUT SAMPLE RATE = 1)
G
0
Figure 9. Combined Half-Band 1 and 2 Pass Band Detail;
Frequency Relative to HB1 Output Sample Rate
相關(guān)PDF資料
PDF描述
AD995PCBZ 1 GSPS Quadrature Digital Upconverter w/18-Bit IQ Data Path and 14-Bit DAC
AD9959 4 Channel 500MSPS DDS with 10-bit DACs
AD9979 14-Bit, CCD Signal Processor with Precision Timing Core
AD9980 High Performance 8-Bit Display Interface
AD9980KSTZ-80 High Performance 8-Bit Display Interface
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AD9958 制造商:AD 制造商全稱:Analog Devices 功能描述:2-Channel 500 MSPS DDS with 10-Bit DACs
AD9958 PCB 制造商:Analog Devices 功能描述:EVAL BOARD ((NS))
AD9958/PCB 制造商:Analog Devices 功能描述:Evaluation Board For 2-Channel 500 MSPS DDS With 10-Bit DACs 制造商:Rochester Electronics LLC 功能描述:- Bulk 制造商:Analog Devices 功能描述:IC 10-BIT DAC DDS
AD9958/PCBZ 功能描述:BOARD EVALUATION FOR AD9958 RoHS:是 類別:編程器,開發(fā)系統(tǒng) >> 評估演示板和套件 系列:AgileRF™ 標(biāo)準(zhǔn)包裝:1 系列:PSoC® 主要目的:電源管理,熱管理 嵌入式:- 已用 IC / 零件:- 主要屬性:- 次要屬性:- 已供物品:板,CD,電源
AD9958/PCBZ 制造商:Analog Devices 功能描述:EVAL BOARD, AD9958 DIRECT DIGITAL SYNTHE