參數(shù)資料
型號: AD7225
廠商: Analog Devices, Inc.
英文描述: ECONOLINE: REC2.2-S_DR/H1 - 2.2W DIP Package- 1kVDC Isolation- Regulated Output- UL94V-0 Package Material- Continuous Short Circiut Protection- Internal SMD design- 100% Burned In- Efficiency to 75%
中文描述: LC2MOS四路8位DAC,帶有單獨的基準(zhǔn)輸入
文件頁數(shù): 10/12頁
文件大?。?/td> 339K
代理商: AD7225
AD7225
REV. B
–10–
FILTER
I/P
I/P
SAMPLES
Am29520
TLD
AD7820
ADC
SAMPLES
AD7225
QUAD DAC
DELAYED
I/P
AD7226
QUAD DAC
V
REF
A
h
1
h
2
V
OUT
A
V
OUT
A
V
OUT
B
V
OUT
C
V
OUT
D
ACCUMULATOR
O/P
AD585
SHA
FILTER
O/P
TAP WEIGHTS
Am7224
DAC
AD584
REF
GAIN SET
+10V
V
OUT
V
REF
V
REF
+
T
T
T
1
2
3
4
h
4
h
3
h
2
h
1
+
FILTER
O/P
Y
n
FILTER
I/P
X
n–1
X
n–2
X
n
X
n–3
V
REF
A
h
3
V
OUT
A
V
REF
A
h
4
V
OUT
A
V
REF
A
V
OUT
A
Figure 18. Programmable Transversal Filter
A 4-tap programmable transversal filter may be implemented
using the AD7225 (Figure 18). T he input signal is first sampled
and converted to allow the tapped delay line function to be pro-
vided by the Am29520. T he multiplication of delayed input
samples by fixed, programmable up weights is accomplished by
the AD7225, the four coefficients or reference inputs being set
by the digital codes stored in the AD7226. T he resultant prod-
ucts are accumulated to yield the convolution sum output
sample which is held by the AD585.
0
–100
0.5
–70
–90
0.05
–80
0
–40
–60
–50
–30
–20
–10
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
NORMALIZED FREQUENCY – f/fs
G
h
1
= 0.117
h
2
= 0.417
h
3
= 0.417
h
4
= 0.417
Figure 19. Predicted (Theoretical) Response
Figure 20. Actual Response
Low pass, bandpass and high pass filters may be synthesized us-
ing this arrangement. T he particular up weights needed for any
desired transfer function may be obtained using the standard
Remez Exchange Algorithm. Figure 19 shows the theoretical
low pass frequency response produced by a 4-tap transversal
filter with the coefficients indicated. Although the theoretical
prediction does not take into account the quantization of the in-
put samples and the truncation of the coefficients, nevertheless,
there exists a good correlation with the actual performance of
the transversal filter (Figure 20).
DIGIT AL WORD MULT IPLICAT ION
Since each DAC of the AD7225 has a separate reference input,
the output of one DAC can be used as the reference input for
another. T his means that multiplication of digital words can be
performed (with the result given in analog form). For example,
if the output from DACA is applied to V
REF
B then the output
from DACB, V
OUT
B, can be expressed as:
V
OUT
B
=
D
A
D
B
V
REF
A
where
D
A
and
D
B
are the fractional representations of the
digital words in DAC latches A and B respectively.
If D
A
= D
B
= D then the result is D
2
V
REF
A
In this manner, the four DACs can be used on their own or in
conjunction with an external summing amplifier to generate
complex waveforms. Figure 21 shows one such application. In
this case the output waveform, Y, is represented by:
Y
= –(
x
4
+ 2
x
3
+ 3
x
2
+ 2
x
+ 4)
V
IN
where
x
is the digital code which is applied to all four DAC
latches.
V
OUT
A
V
OUT
B
V
OUT
C
V
OUT
D
V
REF
A
V
REF
B
V
REF
C
V
REF
D
+15V
V
DD
AD7225*
DGND
AGND
V
SS
V
IN
25k
50k
33k
50k
100k
100k
Y
*DIGITAL INPUTS OMITTED
FOR CLARITY
Figure 21. Complex Waveform Generation
相關(guān)PDF資料
PDF描述
AD7225BQ ECONOLINE: REC2.2-S_DRW(Z)/H* - 2.2W DIP Package- 1kVDC Isolation- Regulated Output- 4.5-9V, 9-18V, 18-36V, 36-72V Wide Input Range 2 : 1- UL94V-0 Package Material- Continuous Short Circiut Protection- Cost Effective- 100% Burned In- Efficiency to 84%
AD7225CQ LC2MOS Quad 8-Bit DAC with Separate Reference Inputs
AD7225LP LC2MOS Quad 8-Bit DAC with Separate Reference Inputs
AD7226 LC2MOS Quad 8-Bit D/A Converter
AD7226BQ LC2MOS Quad 8-Bit D/A Converter
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AD7225BQ 功能描述:IC DAC 8BIT QUAD W/AMP 24-CDIP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉(zhuǎn)換器 系列:- 產(chǎn)品培訓(xùn)模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標(biāo)準(zhǔn)包裝:1,000 系列:- 設(shè)置時間:1µs 位數(shù):8 數(shù)據(jù)接口:串行 轉(zhuǎn)換器數(shù)目:8 電壓電源:雙 ± 功率耗散(最大):941mW 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應(yīng)商設(shè)備封裝:24-SOIC W 包裝:帶卷 (TR) 輸出數(shù)目和類型:8 電壓,單極 采樣率(每秒):*
AD7225BRS 功能描述:IC DAC 8BIT QUAD W/AMP 24-SSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:2,400 系列:- 設(shè)置時間:- 位數(shù):18 數(shù)據(jù)接口:串行 轉(zhuǎn)換器數(shù)目:3 電壓電源:模擬和數(shù)字 功率耗散(最大):- 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:36-TFBGA 供應(yīng)商設(shè)備封裝:36-TFBGA 包裝:帶卷 (TR) 輸出數(shù)目和類型:* 采樣率(每秒):*
AD7225BRS-REEL 功能描述:IC DAC 8BIT QUAD W/AMP 24-SSOP RoHS:否 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉(zhuǎn)換器 系列:- 產(chǎn)品培訓(xùn)模塊:LTC263x 12-, 10-, and 8-Bit VOUT DAC Family 特色產(chǎn)品:LTC2636 - Octal 12-/10-/8-Bit SPI VOUT DACs with 10ppm/°C Reference 標(biāo)準(zhǔn)包裝:91 系列:- 設(shè)置時間:4µs 位數(shù):10 數(shù)據(jù)接口:MICROWIRE?,串行,SPI? 轉(zhuǎn)換器數(shù)目:8 電壓電源:單電源 功率耗散(最大):2.7mW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:14-WFDFN 裸露焊盤 供應(yīng)商設(shè)備封裝:14-DFN-EP(4x3) 包裝:管件 輸出數(shù)目和類型:8 電壓,單極 采樣率(每秒):*
AD7225BRSZ 功能描述:IC DAC 8BIT QUAD W/AMP 24SSOP RoHS:是 類別:集成電路 (IC) >> 數(shù)據(jù)采集 - 數(shù)模轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:47 系列:- 設(shè)置時間:2µs 位數(shù):14 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 電壓電源:單電源 功率耗散(最大):55µW 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:28-SSOP(0.209",5.30mm 寬) 供應(yīng)商設(shè)備封裝:28-SSOP 包裝:管件 輸出數(shù)目和類型:1 電流,單極;1 電流,雙極 采樣率(每秒):*
AD7225CQ 制造商:Rochester Electronics LLC 功能描述:CMOS DAC IC - Bulk