參數(shù)資料
型號(hào): OP90
廠商: Analog Devices, Inc.
英文描述: Precision Low-Voltage Micropower Operational Amplifier
中文描述: 精密低電壓微功率運(yùn)算放大器
文件頁數(shù): 9/12頁
文件大小: 653K
代理商: OP90
REV. A
OP90
–9–
Single Op Amp Full-Wave Rectifier
Figure 7 shows a full-wave rectifier circuit that provides the
absolute value of input signals up to
±
2.5 V even though operated
from a single 5 V supply. For negative inputs, the amplifier acts
as a unity-gain inverter. Positive signals force the op amp output
to ground. The 1N914 diode becomes reversed-biased and the
signal passes through R1 and R2 to the output. Since output
impedance is dependent on input polarity, load impedances
cause an asymmetric output. For constant load impedances, this
can be corrected by reducing R2. Varying or heavy loads can be
buffered by a second OP90. Figure 8 shows the output of the
full-wave rectifier with a 4 V
p-p
, 10 Hz input signal.
+5V
2
3
4
6
OP90FZ
7
R3
100k
HP5082-2800
V
IN
R1
10k
R2
10k
1N914
V
OUT
Figure 7. Single Op Amp Full-Wave Rectifier
Figure 8. Output of Full-Wave Rectifier with 4 V
p-p
,
10 Hz Input
2-WIRE 4 mA TO 20 mA CURRENT TRANSMITTER
The current transmitter of Figure 9 provides an output of 4 mA
to 20 mA that is linearly proportional to the input voltage.
Linearity of the transmitter exceeds 0.004% and line rejection is
0.0005%/volt.
Biasing for the current transmitter is provided by the REF-02EZ.
The OP90EZ regulates the output current to satisfy the current
summation at the noninverting node:
I
R
V
R
2
R
V R
R
OUT
IN
=
+
1
6
5
5
5
1
For the values shown in Figure 9,
I
V
mA
OUT
IN
=
+
16
100
4
giving a full-scale output of 20 mA with a 100 mV input.
Adjustment of R2 will provide an offset trim and adjustment of
R1 will provide a gain trim. These trims do not interact since
the noninverting input of the OP90 is at virtual ground. The
Schottky diode, D1, prevents input voltage spikes from pulling
the noninverting input more than 300 mV below the inverting
input. Without the diode, such spikes could cause phase reversal of
the OP90 and possible latch-up of the transmitter. Compliance of
this circuit is from 10 V to 40 V. The voltage reference output
can provide up to 2 mA for transducer excitation.
2
3
4
6
7
I
OUT
=16V
IN
100
+ 4mA
V
IN
R2
5k
6
4
2
R6
100
R3
4.7k
R4
100k
R1
1M
D1
HP
5082-
2800
R5
80k
+5V
REFERENCE
2mA MAX
+
I
OUT
R
L
2N1711
V+
(10V TO 40V)
OP90EZ
REF-02EZ
Figure 9. 2-Wire 4 mA to 20mA Transmitter
相關(guān)PDF資料
PDF描述
OP97FS Low-Power, High-Precision Operational Amplifier
OP97 Low-Power, High-Precision Operational Amplifier
OP97FP Low-Power, High-Precision Operational Amplifier
OP97FS-REEL Low-Power, High-Precision Operational Amplifier
OP97FS-REEL7 Low-Power, High-Precision Operational Amplifier
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
OP-90 制造商:AD 制造商全稱:Analog Devices 功能描述:PRECISION, LOW VOLTAGE MICROPOWER OPERATIONAL AMPLIFIER
OP900SL 功能描述:光電二極管 PN PHOTODIODE RoHS:否 制造商:Vishay Semiconductors 產(chǎn)品:Photodiodes 反向電壓:10 V 最大暗電流:30 nA 峰值波長(zhǎng):565 nm 上升時(shí)間:3.1 us 下降時(shí)間:3 us 半強(qiáng)度角度:50 deg 封裝 / 箱體:TO-5
OP905 功能描述:光電二極管 Photodiode RoHS:否 制造商:Vishay Semiconductors 產(chǎn)品:Photodiodes 反向電壓:10 V 最大暗電流:30 nA 峰值波長(zhǎng):565 nm 上升時(shí)間:3.1 us 下降時(shí)間:3 us 半強(qiáng)度角度:50 deg 封裝 / 箱體:TO-5
OP906 功能描述:光電二極管 Photodiode RoHS:否 制造商:Vishay Semiconductors 產(chǎn)品:Photodiodes 反向電壓:10 V 最大暗電流:30 nA 峰值波長(zhǎng):565 nm 上升時(shí)間:3.1 us 下降時(shí)間:3 us 半強(qiáng)度角度:50 deg 封裝 / 箱體:TO-5
OP90ARC/883 制造商:AD 制造商全稱:Analog Devices 功能描述:PRECISION, LOW VOLTAGE MICROPOWER OPERATIONAL AMPLIFIER