參數(shù)資料
型號(hào)： OPA3681U
英文描述： Triple Wideband, Current-Feedback OPERATIONAL AMPLIFIER With Disable
中文描述： 三寬帶，電流反饋運(yùn)算放大器，禁用
文件頁(yè)數(shù)： 11/21頁(yè)
文件大?。?/td> 234K
代理商： OPA3681U
11
OPA3681
APPLICATIONS INFORMATION
WIDEBAND CURRENT-FEEDBACK OPERATION
The OPA3681 gives the exceptional AC performance of a
wideband current-feedback op amp with a highly linear,
high power output stage. Requiring only 6mA/ch quiescent
current, the OPA3681 will swing to within 1V of either
supply rail and deliver in excess of 135mA guaranteed at
room temperature. This low output headroom requirement,
along with supply voltage independent biasing, gives re-
markable single (+5V) supply operation. The OPA3681 will
deliver greater than 200MHz bandwidth driving a 2Vp-p
output into 100
on a single +5V supply. Previous boosted
output stage amplifiers have typically suffered from very
poor crossover distortion as the output current goes through
zero. The OPA3681 achieves a comparable power gain with
much better linearity. The primary advantage of a current-
feedback op amp over a voltage-feedback op amp is that AC
performance (bandwidth and distortion) is relatively inde-
pendent of signal gain.
Figure 1 shows the DC-coupled, gain of +2, dual power
supply circuit configuration used as the basis of the
±
5V
Specifications and Typical Performance Curves. For test
purposes, the input impedance is set to 50
with a resistor
to ground and the output impedance is set to 50
with a
series output resistor. Voltage swings reported in the speci-
fications are taken directly at the input and output pins while
load powers (dBm) are defined at a matched 50
load. For
the circuit of Figure 1, the total effective load will be 100
|| 998
. The disable control line (DIS) is typically left open
to guarantee normal amplifier operation. One optional com-
ponent is included in Figure 1. In addition to the usual power
supply de-coupling capacitors to ground, a 0.1
μ
F capacitor
is included between the two power supply pins. In practical
PC board layouts, this optionally added capacitor will typi-
cally improve the 2nd harmonic distortion performance by
3dB to 6dB.
Figure 2 shows the AC-coupled, gain of +2, single-supply
circuit configuration used as the basis of the +5V Specifica-
tions and Typical Performance Curves. Though not a “rail-
to-rail” design, the OPA3681 requires minimal input and
output voltage headroom compared to other very wideband
current-feedback op amps. It will deliver a 3Vp-p output
swing on a single +5V supply with greater than 150MHz
bandwidth. The key requirement of broadband single-supply
operation is to maintain input and output signal swings
within the usable voltage ranges at both the input and the
output. The circuit of Figure 2 establishes an input midpoint
bias using a simple resistive divider from the +5V supply
(two 806
resistors). The input signal is then AC-coupled
into this midpoint voltage bias. The input voltage can swing
to within 1.5V of either supply pin, giving a 2Vp-p input
signal range centered between the supply pins. The input
impedance matching resistor (57.6
) used for testing is
adjusted to give a 50
input match when the parallel
combination of the biasing divider network is included. The
gain resistor (R
G
) is AC-coupled, giving the circuit a DC
gain of +1, which puts the input DC bias voltage (2.5V) on
the output as well. Again, on a single +5V supply, the output
voltage can swing to within 1V of either supply pin while
delivering more than 75mA output current. A demanding
100
load to a midpoint bias is used in this characterization
circuit. The new output stage used in the OPA3681 can
deliver large bipolar output currents into this midpoint load
with minimal crossover distortion, as shown by the +5V
supply, 3rd harmonic distortion plots.
1/3
OPA3681
+5V
+
DIS
–5V
50
Load
50
50
V
O
V
I
50
Source
R
G
499
R
F
499
+
6.8
μ
F
0.1
μ
F
6.8
μ
F
0.1
μ
F
0.1
μ
F
+V
S
–V
S
FIGURE 1. DC-Coupled, G = +2, Bipolar Supply, Specifi-
cation and Test Circuit.
FIGURE 2. AC-Coupled, G = +2, Single Supply, Specifica-
tion and Test Circuit.
1/3
OPA3681
+5V
+V
S
DIS
V
S
/2
806
100
V
O
V
I
57.6
806
R
F
499
R
G
499
0.1
μ
F
0.1
μ
F
6.8
μ
F
+
0.1
μ
F
相關(guān)PDF資料
PDF描述
OPA3682 Triple, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA3682E Triple, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA3682U Triple, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA404KU 256K, 32K X 8, 2.5V HI-SPEED SER EE, -40C to +85C, 8-PDIP, TUBE
OPA4650 Wideband, Low Power, Quad Voltage Feedback OPERATIONAL AMPLIFIER
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
OPA3681U/2K5 制造商:Rochester Electronics LLC 功能描述:- Bulk
OPA3682 制造商:BB 制造商全稱:BB 功能描述:Triple, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA3682E 制造商:BB 制造商全稱:BB 功能描述:Triple, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA3682E/250 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog Buffer/Voltage Follower
OPA3682E/2K5 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog Buffer/Voltage Follower
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

*
*
*