APPLICATIONS INFOR
參數資料
型號: LTC1414IGN#TR
廠商: Linear Technology
文件頁數: 2/20頁
文件大?。?/td> 0K
描述: IC ADC 14BIT 2.2MSPS SMPL 28SSOP
標準包裝: 2,500
位數: 14
采樣率(每秒): 2.2M
數據接口: 并聯
轉換器數目: 1
功率耗散(最大): 230mW
電壓電源: 雙 ±
工作溫度: -40°C ~ 85°C
安裝類型: 表面貼裝
封裝/外殼: 28-SSOP(0.154",3.90mm 寬)
供應商設備封裝: 28-SSOP
包裝: 帶卷 (TR)
輸入數目和類型: 2 個單端,雙極;1 個差分,雙極
10
LTC1414
APPLICATIONS INFORMATION
WU
U
Choosing an Input Amplifier
Choosing an input amplifier is easy if a few requirements
are taken into consideration. First, to limit the magnitude
of the voltage spike seen by the amplifier from charging
the sampling capacitor, choose an amplifier that has a low
output impedance (<100
) at the closed-loop bandwidth
frequency. For example, if an amplifier is used in a gain of
1 and has a unity-gain bandwidth of 50MHz, then the
output impedance at 50MHz must be less than 100
. The
second requirement is that the closed-loop bandwidth
must be greater than 40MHz to ensure adequate small-
signal settling for full throughput rate. If slower op amps
are used, more settling time can be provided by increasing
the time between conversions.
The best choice for an op amp to drive the LTC1414 will
depend on the application. Generally applications fall into
two categories: AC applications where dynamic specifica-
tions are most critical and time domain applications where
DC accuracy and settling time are most critical. The
following list is a summary of the op amps that are suitable
for driving the LTC1414. More detailed information is
available in the Linear Technology Databooks and on the
LinearView
TM CD-ROM.
LT
1223: 100MHz Video Current Feedback Amplifier.
6mA supply current.
±5V to ±15V supplies. Low noise.
Good for AC applications.
LT1227: 140MHz Video Current Feedback Amplifier. 10mA
supply current.
±5V to ±15V supplies. Low noise. Best for
AC applications.
LT1229/LT1230: Dual and Quad 100MHz Current Feed-
back Amplifiers.
±2V to ±15V supplies. Low noise. Good
AC specifications, 6mA supply current each amplifier.
LT1360: 50MHz Voltage Feedback Amplifier. 3.8mA sup-
ply current. Good AC and DC specs.
±5Vto±15Vsupplies.
70ns settling to 0.5LSB.
LT1363: 70MHz, 1000V/
s Op Amps. 6.3mA supply cur-
rent. Good AC and DC specifications. 60ns settling to
0.5LSB.
LT1364/LT1365: Dual and Quad 70MHz, 1000V/
s Op
Amps. 6.3mA supply current per amplifier. 60ns settling
to 0.5LSB.
LinearView is a trademark of Linear Technology Corporation.
AC Coupled Inputs
In applications where only the AC component of the analog
input is important, it may be desirable to AC couple the
input. This is easily accomplished by DC biasing the
LTC1414 analog input with a resistor to ground and using
a coupling capacitor to the input. Figure 7 shows a simple
AC coupled input circuit for the LTC1414 using only two
additional components. C1 is a 10
F ceramic capacitor
and R1 is a 1000
resistor to ground. R1 and C1 form a
highpass filter with a lower cut off frequency of 1/2
π(C1)R1
or 15.9Hz.
Differential Drive
In some applications the ADC drive circuitry is differential.
The differential drive can be applied directly to the LTC1414
without any special translation circuitry. Differential drive
can be advantageous at high frequencies (>1MHz) since it
provides improved THD and SFDR. Transformers can be
used to provide AC coupling, input scaling and single
ended to differential conversion as shown in Figure 8. The
resistor RS across the secondary will determine the input
impedance on the primary. The input impedance of the
primary RP will be related to the secondary load resistor RS
by the equation
RP = RS/n2
For example, if a Minicircuits T4-6T transformer is used,
the turns ratio is 2; if RS is 200 then RP is equal to 50.
The center tap of the secondary will set the common
mode voltage and should be grounded for optimal AC
performance.
LTC1414
AIN
+
ANALOG INPUT
AIN
VREF
REFCOMP
AGND
LTC1414 F07
1
2
3
4
5
R1
1k
C1
10
F
10
F
1
F
Figure 7. AC Coupled Input
相關PDF資料
PDF描述
LTC1411CG#TR IC A/D CONV 14BIT 2.5MSPS 36SSOP
AD1674ARZ-REEL IC ADC SINGLE 12BIT 28SOIC
LTC2859IDD#TRPBF IC TXRX RS485 20MBPS 10-DFN
IDT7201LA50J8 IC MEM FIFO 512X9 50NS 32-PLCC
AD8394ACPZ-R7 IC OPAMP ADSL/ADSL2 DL 24LFCSP
相關代理商/技術參數
參數描述
LTC1415CG 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:12 采樣率(每秒):300k 數據接口:并聯 轉換器數目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應商設備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數目和類型:1 個單端,單極;1 個單端,雙極
LTC1415CG#PBF 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 其它有關文件:TSA1204 View All Specifications 標準包裝:1 系列:- 位數:12 采樣率(每秒):20M 數據接口:并聯 轉換器數目:2 功率耗散(最大):155mW 電壓電源:模擬和數字 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-TQFP 供應商設備封裝:48-TQFP(7x7) 包裝:Digi-Reel® 輸入數目和類型:4 個單端,單極;2 個差分,單極 產品目錄頁面:1156 (CN2011-ZH PDF) 其它名稱:497-5435-6
LTC1415CG#TR 功能描述:IC ADC 12BIT 1.25MSPS SMP 28SSOP RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:12 采樣率(每秒):300k 數據接口:并聯 轉換器數目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應商設備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數目和類型:1 個單端,單極;1 個單端,雙極
LTC1415CG#TRPBF 功能描述:IC A/D CONV 12BIT SAMPLNG 28SSOP RoHS:是 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 產品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,500 系列:- 位數:12 采樣率(每秒):3M 數據接口:- 轉換器數目:- 功率耗散(最大):- 電壓電源:- 工作溫度:- 安裝類型:表面貼裝 封裝/外殼:SOT-23-6 供應商設備封裝:SOT-23-6 包裝:帶卷 (TR) 輸入數目和類型:-
LTC1415CSW 功能描述:IC A/D CONV 12BIT SAMPLNG 28SOIC RoHS:否 類別:集成電路 (IC) >> 數據采集 - 模數轉換器 系列:- 標準包裝:1,000 系列:- 位數:12 采樣率(每秒):300k 數據接口:并聯 轉換器數目:1 功率耗散(最大):75mW 電壓電源:單電源 工作溫度:0°C ~ 70°C 安裝類型:表面貼裝 封裝/外殼:24-SOIC(0.295",7.50mm 寬) 供應商設備封裝:24-SOIC 包裝:帶卷 (TR) 輸入數目和類型:1 個單端,單極;1 個單端,雙極