- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄363771 > OPA2379AIDRG4 1.8V, 2.9uA, 90kHz, Rail-to-Rail I/O OPERATIONAL AMPLIFIERS PDF資料下載
參數(shù)資料
| 型號： | OPA2379AIDRG4 |
| 英文描述： | 1.8V, 2.9uA, 90kHz, Rail-to-Rail I/O OPERATIONAL AMPLIFIERS |
| 中文描述： | 1.8，2.9uA，90kHz，軌對軌輸入/輸出運(yùn)算放大器 |
| 文件頁數(shù)： | 8/12頁 |
| 文件大?。?/td> | 238K |
| 代理商： | OPA2379AIDRG4 |
"#$
%"#$
&"#$
SBOS347A NOVEMBER 2005 REVISED DECEMBER 2005
www.ti.com
8
In unity-gain inverter configuration, phase margin can be
reduced by the reaction between the capacitance at the op
amp input and the gain setting resistors, thus degrading
capacitive load drive. Best performance is achieved by
using smaller valued resistors. However, when large
valued resistors cannot be avoided, a small (4pF to 6pF)
capacitor, C
FB
, can be inserted in the feedback, as shown
in Figure 3. This configuration significantly reduces
overshoot by compensating the effect of capacitance, C
IN
,
which includes the amplifier input capacitance and PC
board parasitic capacitance.
R
I
OPA379
V
IN
V
OUT
R
F
C
FB
C
IN
C
L
Figure 3. Improving Capacitive Load Drive
BATTERY MONITORING
The low operating voltage and quiescent current of the
OPA379 series make it an excellent choice for battery
monitoring applications, as shown in Figure 4. In this
circuit, V
STATUS
will be high as long as the battery voltage
remains above 2V. A low-power reference is used to set
the trip point. Resistor values are selected as follows:
1.
Selecting R
F
: Select R
F
such that the current through R
F
is approximately 1000x larger than the maximum bias
current over temperature:
R
F
V
REF
1000 I
BMAX
1.2V
1000
(
100pA
)
12M
10M
2.
Choose the hysteresis voltage, V
HYST
. For battery-
monitoring applications, 50mV is adequate.
3.
Calculate R
1
as follows:
R
1
R
F
V
HYST
V
BATT
10M
50mV
2.4V
210k
4.
Select a threshold voltage for V
IN
rising (V
THRS
) = 2.0V
5.
Calculate R
2
as follows:
R
2
1
VTHRS
VREF
R1
1
R1
1
RF
1
2V
1.2V
210k
1
210k
1
10M
325k
6.
Calculate R
BIAS
: The minimum supply voltage for this
circuit will be 1.8V. The REF1112 has a current
requirement of 1.2
μ
A (max). Providing it 2
μ
A of supply
current assures proper operation. Therefore:
R
BIAS
V
BATTMIN
I
BIAS
1.8V
2 A
0.9M
REF1112
OPA379
+IN
OUT
IN
V
STATUS
V
BATT
V
REF
R
1
R
2
R
BIAS
I
BIAS
R
F
+
Figure 4. Battery Monitor
(1)
(2)
(3)
(4)
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| OPA237NA250E4 | SINGLE-SUPPLY OPERATIONAL AMPLIFIERS MicroAmplifier⑩ Series |
| OPA2237 | SINGLE-SUPPLY OPERATIONAL AMPLIFIERS MicroAmplifier⑩ Series |
| OPA2237EA250 | SINGLE-SUPPLY OPERATIONAL AMPLIFIERS MicroAmplifier⑩ Series |
| OPA2237EA250G4 | SINGLE-SUPPLY OPERATIONAL AMPLIFIERS MicroAmplifier⑩ Series |
| OPA2237EA2K5 | SINGLE-SUPPLY OPERATIONAL AMPLIFIERS MicroAmplifier⑩ Series |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| OPA237NA | 制造商:Texas Instruments 功能描述:OP AMP SINGLESUPPLY SMD SOT235 |
| OPA237NA/250 | 功能描述:運(yùn)算放大器 - 運(yùn)放 Sgl-Supply Op Amp MicroAmp Series 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(bǔ)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(fēng)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 |
| OPA237NA/250 | 制造商:Texas Instruments 功能描述:IC SM OP-AMP SINGLE-SUPPLY |
| OPA237NA/250E4 | 功能描述:運(yùn)算放大器 - 運(yùn)放 Single MicroAmp 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(bǔ)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(fēng)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 |
| OPA237NA/3K | 功能描述:運(yùn)算放大器 - 運(yùn)放 Sgl-Sply Op Amp MicroAmp(TM) Series 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(bǔ)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(fēng)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 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。