Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.COM

X  

OPA3680 Datasheet(PDF) 11 Page - Texas Instruments

Part # OPA3680
Description  Triple, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER
Download  22 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  TI1 [Texas Instruments]
Direct Link  http://www.ti.com
Logo TI1 - Texas Instruments

OPA3680 Datasheet(HTML) 11 Page - Texas Instruments

Back Button OPA3680 Datasheet HTML 7Page - Texas Instruments OPA3680 Datasheet HTML 8Page - Texas Instruments OPA3680 Datasheet HTML 9Page - Texas Instruments OPA3680 Datasheet HTML 10Page - Texas Instruments OPA3680 Datasheet HTML 11Page - Texas Instruments OPA3680 Datasheet HTML 12Page - Texas Instruments OPA3680 Datasheet HTML 13Page - Texas Instruments OPA3680 Datasheet HTML 14Page - Texas Instruments OPA3680 Datasheet HTML 15Page - Texas Instruments Next Button
Zoom Inzoom in Zoom Outzoom out
 11 / 22 page
background image
11
®
OPA3680
APPLICATIONS INFORMATION
WIDEBAND VOLTAGE FEEDBACK OPERATION
The OPA3680 provides an exceptional combination of high
output power capability with a wideband, unity gain stable
voltage feedback op amp using a new high slew rate input
stage. Typical differential input stages used for voltage
feedback op amps are designed to steer a fixed-bias current
to the compensation capacitor, setting a limit to the achiev-
able slew rate. The OPA3680 uses a new input stage which
places the transconductance element between two input
buffers, using their output currents as the forward signal. As
the error voltage increases across the two inputs, an increas-
ing current is delivered to the compensation capacitor. This
provides very high slew rate (1800V/
µs) while consuming
relatively low quiescent current (6.4mA). This exceptional
full power performance comes at the price of a slightly
higher input noise voltage than alternative architectures. The
4.8nV/
√Hz input voltage noise for the OPA3680 is excep-
tionally low for this type of input stage.
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
Ω with a resistor to
ground and the output impedance is set to 50
Ω with a series
output resistor. Voltage swings reported in the specifications
are taken directly at the input and output pins, while output
powers (dBm) are at the matched 50
Ω load. For the circuit of
Figure 1, the total effective load will be 100
Ω || 498Ω. The
disable control line is typically left open to guarantee normal
amplifier operation. Two optional components are included
in Figure 1. An additional resistor (100
Ω) is included in
series with the non-inverting input. Combined with the 25
DC source resistance looking back towards the signal genera-
tor, this gives an input bias current cancelling resistance that
matches the 125
Ω source resistance seen at the inverting
input (see the DC Accuracy and Offset Control section). In
addition to the usual power supply decoupling capacitors to
ground, a 0.1
µF capacitor is included between the two power
supply pins. In practical PC board layouts, this optional-
added capacitor will typically improve the 2nd harmonic
distortion performance by 3dB to 6dB.
Figure 2 shows the AC-coupled, gain of +2, single supply
circuit configuration which is the basis of the +5V Specifi-
cations and Typical Performance Curves. Though not a “rail-
to-rail” design, the OPA3680 requires minimal input and
output voltage headroom compared to other very wideband
voltage feedback op amps. It will deliver a 3Vp-p output
swing on a single +5V supply with >150MHz bandwidth.
The key requirement of broadband single-supply operation is
to maintain input and output signal swings within the useable
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 402
Ω resistors).
The input signal is then AC-coupled into the 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 (68
Ω) used for testing is adjusted to give a 50Ω input
load when the parallel combination of the biasing divider
network is included. Again, an additional resistor (50
Ω in
this case) is included directly in series with the non-inverting
input. This minimum recommended value provides part of
the DC source resistance matching for the non-inverting
input bias current. It is also used to form a simple parasitic
pole to roll off the frequency response at very high frequen-
cies (>500MHz) using the input parasitic capacitance to
form a bandlimiting pole. The gain resistor (RG) is AC-
coupled, giving the circuit a DC gain of +1, which puts the
input DC bias voltage (2.5V) at the output as well. The
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
OPA3680
+5V
+
DIS
–5V
50
Ω Load
50
50
100
V
O
+V
S
–V
S
V
I
50
Ω Source
R
G
249
R
F
249
+
6.8
µF
0.1
µF
6.8
µF
0.1
µF
0.1
µF
1/3
OPA3680
+5V
+V
S
DIS
V
S/2
402
50
68
100
V
O
V
I
402
R
G
249
R
F
249
0.1
µF
0.1
µF
+
6.8
µF
0.1
µF


Similar Part No. - OPA3680

ManufacturerPart #DatasheetDescription
logo
Burr-Brown (TI)
OPA3680 BURR-BROWN-OPA3680 Datasheet
225Kb / 21P
   Triple, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER With Disable
logo
Texas Instruments
OPA3680 TI1-OPA3680 Datasheet
195Kb / 20P
[Old version datasheet]   Dual, Wideband, Fixed Gain BUFFER AMPLIFIER With Disable
OPA3680 TI1-OPA3680 Datasheet
833Kb / 23P
[Old version datasheet]   Dual, 700MHz, Voltage-Feedback OPERATIONAL AMPLIFIER
OPA3680 TI1-OPA3680 Datasheet
217Kb / 22P
[Old version datasheet]   Dual Wideband, Voltage Feedback OPERATIONAL AMPLIFIER With Disable
OPA3680 TI1-OPA3680 Datasheet
377Kb / 22P
[Old version datasheet]   Dual Wideband, Current Feedback OPERATIONAL AMPLIFIER
More results

Similar Description - OPA3680

ManufacturerPart #DatasheetDescription
logo
Texas Instruments
OPA3690 TI1-OPA3690_14 Datasheet
1Mb / 39P
[Old version datasheet]   Triple, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER
logo
Burr-Brown (TI)
OPA3680 BURR-BROWN-OPA3680 Datasheet
225Kb / 21P
   Triple, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER With Disable
logo
Texas Instruments
OPA3681 TI1-OPA3681 Datasheet
401Kb / 22P
[Old version datasheet]   Triple Wideband, Current-Feedback OPERATIONAL AMPLIFIER
OPA3691 TI1-OPA3691 Datasheet
1Mb / 32P
[Old version datasheet]   Triple Wideband, Current-Feedback OPERATIONAL AMPLIFIER
OPA3690ID TI-OPA3690ID Datasheet
1Mb / 39P
[Old version datasheet]   Triple, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER with Disable
logo
Burr-Brown (TI)
OPA640 BURR-BROWN-OPA640 Datasheet
190Kb / 13P
   Wideband Voltage Feedback OPERATIONAL AMPLIFIER
OPA641 BURR-BROWN-OPA641 Datasheet
106Kb / 13P
   Wideband Voltage Feedback OPERATIONAL AMPLIFIER
logo
Texas Instruments
OPA640 TI1-OPA640 Datasheet
139Kb / 14P
[Old version datasheet]   Wideband Voltage Feedback OPERATIONAL AMPLIFIER
OPA680 TI1-OPA680 Datasheet
248Kb / 22P
[Old version datasheet]   Wideband, Voltage Feedback OPERATIONAL AMPLIFIER
logo
Burr-Brown (TI)
OPA3681 BURR-BROWN-OPA3681 Datasheet
234Kb / 21P
   Triple Wideband, Current-Feedback OPERATIONAL AMPLIFIER With Disable
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com