參數(shù)資料
型號(hào)： AD9243AS
廠商： ANALOG DEVICES INC
元件分類(lèi)： ADC
英文描述： Complete 14-Bit, 3.0 MSPS Monolithic A/D Converter
中文描述： 1-CH 14-BIT FLASH METHOD ADC, PARALLEL ACCESS, PQFP44
封裝： MQFP-44
文件頁(yè)數(shù)： 9/24頁(yè)
文件大小： 545K
代理商： AD9243AS
AD9243
REV. A
–9–
The input SHA of the AD9243 is optimized to meet the perfor-
mance requirements for some of the most demanding commu-
nication, imaging, and data acquisition applications while
maintaining low power dissipation. Figure 22 is a graph of the
full-power bandwidth of the AD9243, typically 40 MHz. Note
that the small signal bandwidth is the same as the full-power
bandwidth. The settling time response to a full-scale stepped
input is shown in Figure 23 and is typically 80 ns to 0.0025%.
The low input referred noise of 0.36 LSB’s rms is displayed via
a grounded histogram and is shown in Figure 13.
FREQUENCY – MHz
0
–3
–12
1
100
10
A
–6
–9
Figure 22. Full-Power Bandwidth
SETTLING TIME – ns
C
16000
12000
0
0
60
10
20
30
40
50
8000
4000
70
80
Figure 23. Settling Time
The SHA’s optimum
distortion
performance for a differential or
single-ended input is achieved under the following two condi-
tions: (1) the common-mode voltage is centered around mid
supply (i.e., AVDD/2 or approximately 2.5 V) and (2) the input
signal voltage span of the SHA is set at its lowest (i.e., 2 V input
span). This is due to the sampling switches, Q
S1
, being CMOS
switches whose R
ON
resistance is very low but has some signal
dependency which causes frequency dependent ac distortion
while the SHA is in the track mode. The R
ON
resistance of a
CMOS switch is typically lowest at its midsupply but increases
symmetrically as the input signal approaches either AVDD or
AVSS. A lower input signal voltage span centered at midsupply
reduces the degree of R
ON
modulation.
Figure 24 compares the AD9243’s THD vs. frequency perfor-
mance for a 2 V input span with a common-mode voltage of
1 V and 2.5 V. Note the difference in the amount of degrada-
tion in THD performance as the input frequency increases.
Similarly, note how the THD performance at lower frequencies
becomes less sensitive to the common-mode voltage. As the
input frequency approaches dc, the distortion will be domi-
nated by static nonlinearities such as INL and DNL. It is
important to note that these dc static nonlinearities are inde-
pendent of any R
ON
modulation.
FREQUENCY – MHz
T
–50
–60
–90
0.1
1
10
–70
–80
V
CM
= 1.0V
V
CM
= 2.5V
Figure 24. AD9243 THD vs. Frequency for V
CM
= 2.5 V and
1.0 V (A
IN
= –0.5 dB, Input Span = 2.0 V p-p)
Due to the high degree of symmetry within the SHA topology, a
significant improvement in distortion performance for differen-
tial input signals with frequencies up to and beyond Nyquist can
be realized. This inherent symmetry provides excellent cancella-
tion of both common-mode distortion and noise. Also, the
required input signal voltage span is reduced by a half which
further reduces the degree of R
ON
modulation and its effects on
distortion.
The optimum
noise and dc linearity
performance for either
differential or single-ended inputs is achieved with the largest
input signal voltage span (i.e., 5 V input span) and matched
input impedance for VINA and VINB. Note that only a slight
degradation in dc linearity performance exists between the
2 V and 5 V input span as specified in the AD9243 “DC
SPECIFICATIONS.”
Referring to Figure 21, the differential SHA is implemented
using a switched-capacitor topology. Hence, its input imped-
ance and its subsequent effects on the input drive source should
be understood to maximize the converter’s performance. The
combination of the pin capacitance, C
PIN
, parasitic capacitance
C
PAR,
and the sampling capacitance, C
S
, is typically less than
16 pF. When the SHA goes into track mode, the input source
must charge or discharge the voltage stored on C
S
to the new
input voltage. This action of charging and discharging C
S
which
is approximately 4 pF, averaged over a period of time and for a
given sampling frequency, F
S
, makes the input impedance ap-
pear to have a benign resistive component (i.e., 83 k
at F
S
=
3.0 MSPS). However, if this action is analyzed within a sam-
pling period (i.e., T = <1/F
S
), the input impedance is dynamic
due to the instantaneous requirement of charging and discharg-
ing C
S
. A series resistor inserted between the input drive source
and the SHA input as shown in Figure 25 provides the effective
isolation.
相關(guān)PDF資料
PDF描述
AD9243EB Complete 14-Bit, 3.0 MSPS Monolithic A/D Converter
AD9243* 14-Bit Rail-to-Rail DACs with I2C Interface; Package: DFN; No of Pins: 10; Temperature Range: 0&deg;C to +70&deg;C
AD9244 14-Bit, 40/65 MSPS Monolithic A/D Converter
AD9244-40PCB 14-Bit, 40/65 MSPS Monolithic A/D Converter
AD9244-65PCB 14-Bit, 40/65 MSPS Monolithic A/D Converter
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AD9243ASRL 制造商:Analog Devices 功能描述:ADC Single Pipelined 3Msps 14-bit Parallel 44-Pin MQFP T/R
AD9243ASZ 功能描述:IC ADC 14BIT 3MSPS 44-MQFP RoHS:是 類(lèi)別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1 系列:microPOWER™ 位數(shù):8 采樣率（每秒）:1M 數(shù)據(jù)接口:串行，SPI? 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:- 電壓電源:模擬和數(shù)字 工作溫度:-40°C ~ 125°C 安裝類(lèi)型:表面貼裝 封裝/外殼:24-VFQFN 裸露焊盤(pán) 供應(yīng)商設(shè)備封裝:24-VQFN 裸露焊盤(pán)（4x4） 包裝:Digi-Reel® 輸入數(shù)目和類(lèi)型:8 個(gè)單端，單極 產(chǎn)品目錄頁(yè)面:892 (CN2011-ZH PDF) 其它名稱:296-25851-6
AD9243ASZRL 功能描述:IC ADC 14BIT SGL 3MSPS 44MQFP RoHS:是 類(lèi)別:集成電路 (IC) >> 數(shù)據(jù)采集 - 模數(shù)轉(zhuǎn)換器 系列:- 標(biāo)準(zhǔn)包裝:1,000 系列:- 位數(shù):12 采樣率（每秒）:300k 數(shù)據(jù)接口:并聯(lián) 轉(zhuǎn)換器數(shù)目:1 功率耗散（最大）:75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類(lèi)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 包裝:帶卷 (TR) 輸入數(shù)目和類(lèi)型:1 個(gè)單端，單極；1 個(gè)單端，雙極
AD9243EB 制造商:AD 制造商全稱:Analog Devices 功能描述:Complete 14-Bit, 3.0 MSPS Monolithic A/D Converter
AD9243-EB 制造商:Analog Devices 功能描述:Evaluation Board For AD9243 制造商:Analog Devices 功能描述:DEV TOOLS, EVAL BD FOR AD9243 - Bulk
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*