參數(shù)資料
型號: THS4502CDGKG4
廠商: Texas Instruments, Inc.
元件分類: 運(yùn)動控制電子
英文描述: WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
中文描述: 寬帶,低失真全差動放大器
文件頁數(shù): 22/40頁
文件大?。?/td> 609K
代理商: THS4502CDGKG4
THS4502
THS4503
SLOS352D
APRIL 2002
REVISED JANUARY 2004
www.ti.com
22
CHOOSING THE PROPER VALUE FOR THE
FEEDBACK AND GAIN RESISTORS
The selection of feedback and gain resistors impacts
circuit performance in a number of ways. The values in this
section provide the optimum high frequency performance
(lowest distortion, flat frequency response). Since the
THS4500 family of amplifiers is developed with a voltage
feedback architecture, the choice of resistor values does
not have a dominant effect on bandwidth, unlike a current
feedback amplifier. However, resistor choices do have
second-order effects. For optimal performance, the
following feedback resistor values are recommended. In
higher gain configurations (gain greater than two), the
feedback resistor values have much less effect on the high
frequency performance. Example feedback and gain
resistor values are given in the section on basic design
considerations (Table 3).
Amplifier loading, noise, and the flatness of the frequency
response are three design parameters that should be
considered when selecting feedback resistors. Larger
resistor values contribute more noise and can induce
peaking in the ac response in low gain configurations, and
smaller resistor values can load the amplifier more heavily,
resulting in a reduction in distortion performance. In
addition, feedback resistor values, coupled with gain
requirements, determine the value of the gain resistors,
directly impacting the input impedance of the entire circuit.
While there are no strict rules about resistor selection,
these trends can provide qualitative design guidance.
APPLICATION CIRCUITS USING FULLY
DIFFERENTIAL AMPLIFIERS
Fully differential amplifiers provide designers with a great
deal of flexibility in a wide variety of applications. This
section provides an overview of some common circuit
configurations and gives some design guidelines.
Designing the interface to an ADC, driving lines
differentially, and filtering with fully differential amplifiers
are a few of the circuits that are covered.
BASIC DESIGN CONSIDERATIONS
The circuits in Figures 96 through 100 are used to highlight
basic design considerations for fully differential amplifier
circuit designs.
Table 3. Resistor Values for Balanced Operation
in Various Gain Configurations
Gain
V
OD
V
IN
1
R2 & R4 (
)
R1 (
)
R3 (
)
R
T
(
)
392
412
383
54.9
1
499
523
487
53.6
2
392
215
187
60.4
2
1.3k
665
634
52.3
5
1.3k
274
249
56.2
5
3.32k
681
649
52.3
10
1.3k
147
118
64.9
10
6.81k
698
681
52.3
NOTE
:
Values in the table above assume a 50
source impedance.
V
OCM
V
n
V
S
R
S
R1
R
T
R2
R4
+
+
V
out+
V
out
R3
V
P
Figure 96
Equations for calculating fully differential amplifier resistor
values in order to obtain balanced operation in the
presence of a 50-
source impedance are given in
equations 6 through 9.
R
T
1
1
R
S
1
K
2(1
R3
K)
K
R2
R1
R2
R4
R3
R1
R
s
|| R
T
(6)
β
1
R1
R1
R2
β
2
R3
R
T
|| R
S
R
T
|| R
S
R3
R4
V
OD
V
S
2
1
β
2
β
1
β
2
R
T
R
T
R
S
V
OD
V
IN
2
1
β
2
β
1
β
2
(7)
(8)
(9)
For more detailed information about balance in fully
differential amplifiers, see
Fully Differential Amplifiers
,
referenced at the end of this data sheet.
相關(guān)PDF資料
PDF描述
THS4502CDGKR WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
THS4502CDGKRG4 WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
THS4502CDGKT WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
THS4502CDGNT WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
THS4502CDR WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
THS4502CDGKR 功能描述:特殊用途放大器 Hi-Sp Fully-Diff Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量:Single 共模抑制比(最小值): 輸入補(bǔ)償電壓: 工作電源電壓:3 V to 5.5 V 電源電流:5 mA 最大功率耗散: 最大工作溫度:+ 70 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-20 封裝:Reel
THS4502CDGKRG4 功能描述:特殊用途放大器 Hi-Sp Fully-Diff Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量:Single 共模抑制比(最小值): 輸入補(bǔ)償電壓: 工作電源電壓:3 V to 5.5 V 電源電流:5 mA 最大功率耗散: 最大工作溫度:+ 70 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-20 封裝:Reel
THS4502CDGKT 制造商:TI 制造商全稱:Texas Instruments 功能描述:WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS
THS4502CDGN 功能描述:特殊用途放大器 HS Full Diff RoHS:否 制造商:Texas Instruments 通道數(shù)量:Single 共模抑制比(最小值): 輸入補(bǔ)償電壓: 工作電源電壓:3 V to 5.5 V 電源電流:5 mA 最大功率耗散: 最大工作溫度:+ 70 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-20 封裝:Reel
THS4502CDGNDT 制造商:TI 制造商全稱:Texas Instruments 功能描述:WIDEBAND, LOW-DISTORTION FULLY DIFFERENTIAL AMPLIFIERS