- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄358885 > LMV721M7 (NATIONAL SEMICONDUCTOR CORP) 10MHz, Low Noise, Low Voltage, and Low Power Operational Amplifier PDF資料下載
參數(shù)資料
| 型號： | LMV721M7 |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 運動控制電子 |
| 英文描述： | 10MHz, Low Noise, Low Voltage, and Low Power Operational Amplifier |
| 中文描述： | OP-AMP, 3000 uV OFFSET-MAX, 10 MHz BAND WIDTH, PDSO5 |
| 封裝： | 2 X 2 MM, 1 MM HEIGHT, SC-70, 5 PIN |
| 文件頁數(shù)： | 9/15頁 |
| 文件大?。?/td> | 459K |
| 代理商： | LMV721M7 |
Application Notes
(Continued)
loop. Increased capacitive drive is possible by increasing the
value of C
F
. This in turn will slow down the pulse response.
3.0 Input Bias Current Cancellation
The LMV721/722 family has a bipolar input stage. The typi-
cal input bias current of LMV721/722 is 260nA with 5V sup-
ply. Thus a 100k
input resistor will cause 26mV of error
voltage. By balancing the resistor values at both inverting
and non-inverting inputs, the error caused by the amplifier’s
input bias current will be reduced. The circuit in Figure 4
shows how to cancel the error caused by input bias current.
4.0 Typical Single-Supply Application Circuits
4.1 Difference amplifier
The difference amplifier allows the subtraction of two volt-
ages or, as a special case, the cancellation of a signal com-
mon to two inputs. It is useful as a computational amplifier, in
making a differential to single-ended conversion or in reject-
ing a common mode signal.
4.2 Instrumentation Circuits
The input impendance of the previous difference amplifier is
set by the resistor R
, R
, R
and R
. To eliminate the prob-
lems of low input impendance, one way is to use a voltage
follower ahead of each input as shown in the following two
instrumentation amplifiers.
4.2.1 Three-op-amp Instrumentation Amplifier
The LMV721/722 can be used to build a three-op-amp in-
strumentation amplifier as shown in Figure 6
The first stage of this instrumentation amplifier is a
differential-input, differential-output amplifier, with two volt-
age followers. These two voltage followers assure that the
input impedance is over 100M
. The gain of this instrumen-
tation amplifier is set by the ratio of R
/R
1
. R
should equal
R
and R
equal R
. Matching of R
to R
and R
to R
af-
fects the CMRR. For good CMRR over temperature, low drift
resistors should be used. Making R
slightly smaller than R
2
and adding a trim pot equal to twice the difference between
R
2
and R
4
will allow the CMRR to be adjusted for optimum.
4.2.2 Two-op-amp Instrumentation Amplifier
A two-op-amp instrumentation amplifier can also be used to
make a high-input impedance DC differential amplifier (Fig-
ure 7). As in the two-op-amp circuit, this instrumentation am-
plifier requires precise resistor matching for good CMRR. R
4
should equal to R
1
and R
3
should equal R
2
.
DS100922-19
FIGURE 3. Indirectly Driving A Capacitive Load with
DC Accuracy
DS100922-20
FIGURE 4. Cancelling the Error Caused by Input Bias
Current
DS100922-21
FIGURE 5. Difference Application
DS100922-30
FIGURE 6. Three-op-amp Instrumentation Amplifier
www.national.com
9
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LMV721M5X | 10MHz, Low Noise, Low Voltage, and Low Power Operational Amplifier |
| LMV721M5 | 10MHz, Low Noise, Low Voltage, and Low Power Operational Amplifier |
| LMV7239 | 45ns, Ultra Low Power, Low Voltage, Rail-to-Rail Input Comparator with Open-Drain/Push-Pull Output |
| LMV7239M5 | DIODE ZENER SINGLE 200mW 11Vz 20mA-Izt 0.05 2uA-Ir 8.4 SOT-323 3K/REEL |
| LMV7239M5X | 45ns, Ultra Low Power, Low Voltage, Rail-to-Rail Input Comparator with Open-Drain/Push-Pull Output |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LMV721M7 | 制造商:Texas Instruments 功能描述:OP AMP ULTRA LOW NOISE POWERWISE |
| LMV721M7/NOPB | 功能描述:運算放大器 - 運放 Ultra Low Noise Sgl Op Amp RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| LMV721M7X | 功能描述:運算放大器 - 運放 RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| LMV721M7X/NOPB | 功能描述:運算放大器 - 運放 RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| LMV721-N | 制造商:TI 制造商全稱:Texas Instruments 功能描述:LMV721-N/LMV722 10MHz, Low Noise, Low Voltage, and Low Power Operational Amplifier |
發(fā)布緊急采購，3分鐘左右您將得到回復。