- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384440 > HS-1120RH (Intersil Corporation) Radiation Hardened, Ultra High Speed Current Feedback Amplifier with Offset Adjust(抗輻射超高速電流反饋放大器（可調(diào)節(jié)漂移）) PDF資料下載
參數(shù)資料
| 型號： | HS-1120RH |
| 廠商： | Intersil Corporation |
| 英文描述： | Radiation Hardened, Ultra High Speed Current Feedback Amplifier with Offset Adjust(抗輻射超高速電流反饋放大器（可調(diào)節(jié)漂移）) |
| 中文描述： | 輻射加固，超高速電流反饋放大器的偏移調(diào)整（抗輻射超高速電流反饋放大器（可調(diào)節(jié)漂移）） |
| 文件頁數(shù)： | 2/11頁 |
| 文件大小： | 119K |
| 代理商： | HS-1120RH |
2
Application Information
Optimum Feedback Resistor
The enclosed plots of inverting and non-inverting frequency
response illustrate the performance of the HS-1120RH in
various gains. Although the bandwidth dependency on
closed loop gain isn’t as severe as that of a voltage feedback
amplifier, there can be an appreciable decrease in
bandwidth at higher gains. This decrease may be minimized
by taking advantage of the current feedback amplifier’s
unique relationship between bandwidth and R
F
. All current
feedback amplifiers require a feedback resistor, even for
unity gain applications, and R
F
, in conjunction with the
internal compensation capacitor, sets the dominant pole of
the frequency response. Thus, the amplifier’s bandwidth is
inversely proportional to R
F
. The HS-1120RH design is
optimized for a 510
R
F
at a gain of +1. Decreasing R
F
in a
unity gain application decreases stability, resulting in
excessive peaking and overshoot. At higher gains the
amplifier is more stable, so R
F
can be decreased in a trade-
off of stability for bandwidth.
The table below lists recommended R
F
values for various
gains, and the expected bandwidth.
PC Board Layout
The frequency response of this amplifier depends greatly on
the amount of care taken in designing the PC board.
The
use of low inductance components such as chip resis-
tors and chip capacitors is strongly recommended,
while a solid ground plane is a must!
Attention should be given to decoupling the power supplies.
A large value (10
μ
F) tantalum in parallel with a small value
(0.1
μ
F) chip capacitor works well in most cases.
Terminated microstrip signal lines are recommended at the
input and output of the device. Capacitance directly on the
output must be minimized, or isolated as discussed in the
next section.
Care must also be taken to minimize the capacitance to
ground seen by the amplifier’s inverting input (-IN). The
larger this capacitance, the worse the gain peaking, resulting
in pulse overshoot and possible instability. To this end, it is
recommended that the ground plane be removed under
traces connected to -IN, and connections to -IN should be
kept as short as possible.
An example of a good high frequency layout is the Evalua-
tion Board shown in Figure 2.
Driving Capacitive Loads
Capacitive loads, such as an A/D input, or an improperly
terminated transmission line will degrade the amplifier’s
phase margin resulting in frequency response peaking and
possible oscillations. In most cases, the oscillation can be
avoided by placing a resistor (R
S
) in series with the output
prior to the capacitance.
Figure 1 details starting points for the selection of this resis-
tor. The points on the curve indicate the R
S
and C
L
combina-
tions for the optimum bandwidth, stability, and settling time,
but experimental fine tuning is recommended. Picking a
point above or to the right of the curve yields an overdamped
response, while points below or left of the curve indicate
areas of underdamped performance.
R
S
and C
L
form a low pass network at the output, thus
limiting system bandwidth well below the amplifier band-
width of 850MHz. By decreasing R
S
as C
L
increases (as
illustrated in the curves), the maximum bandwidth is
obtained without sacrificing stability. Even so, bandwidth
does decrease as you move to the right along the curve.
For example, at A
V
= +1, R
S
= 50
, C
L
= 30pF, the overall
bandwidth is limited to 300MHz, and bandwidth drops to
100MHz at A
V
= +1, R
S
= 5
, C
L
= 340pF.
Evaluation Board
The performance of the HS-1120RH may be evaluated using
the HFA11XXEVAL Evaluation Board.
The layout and schematic of the board are shown in
Figure 2. To order evaluation boards, please contact your
local sales office.
Offset Adjustment
The output offset voltage of the HS-1120RH may be nulled via
connections to the BAL pins. Unlike a voltage feedback
amplifier, offset adjustment is accomplished by varying the sign
and/or magnitude of the inverting input bias current (-I
BIAS
).
With voltage feedback amplifiers, bias currents are matched
and bias current induced offset errors are nulled by matching
the impedances seen at the positive and negative inputs. Bias
GAIN
(A
CL
)
R
F
(
)
BANDWIDTH
(MHz)
-1
430
580
+1
510
850
+2
360
670
+5
150
520
+10
180
240
+19
270
125
R
S
)
LOAD CAPACITANCE (pF)
50
45
40
35
30
25
20
15
10
5
0
0
40
80
120
160
200
240
280
320
360
400
A
V
= +1
A
V
= +2
FIGURE 1. RECOMMENDED SERIES OUTPUT RESISTOR vs
LOAD CAPACITANCE
HS-1120RH
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| HS-1145RH | Radiation Hardened, High Speed, Low Power, Current Feedback Video Operational Amplifier with Output Disable(抗輻射超高速電流反饋視頻運算放大器（帶輸出禁止）) |
| HS7-1145RH-Q | CONNECTOR ACCESSORY |
| HS7B-1145RH-Q | Radiation Hardened, High Speed, Low Power, Current Feedback Video Operational Amplifier with Output Disable |
| HS-117RH | Adjustable Positive Voltage Regulator(可調(diào)正輸出穩(wěn)壓器) |
| HS-1410RH | Radiation Hardened, High Speed, Low Power, Current Feedback Op Amp with Output Disable(抗輻射高速、低功耗電流反饋放大器（輸出禁止）) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| HS-1120RH-Q | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Current-Feedback Operational Amplifier |
| HS11240-50 | 制造商:GROOV-PIN 功能描述: |
| HS1-1245RH-Q | 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Radiation Hardened, Dual, High Speed, Low Power Video Operational Amplifier with Output Disable |
| HS-113 | 制造商:Hozan Tool Industrial Co Ltd 功能描述: |
| HS-1135RH | 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Radiation Hardened, High Speed, Low Power Current Feedback Amplifier with Programmable Output Limiting |
發(fā)布緊急采購，3分鐘左右您將得到回復。