- 您現(xiàn)在的位置：買(mǎi)賣(mài)IC網(wǎng) > PDF目錄363781 > OPA689P Wideband, High Gain VOLTAGE LIMITING AMPLIFIER PDF資料下載
參數(shù)資料
| 型號(hào)： | OPA689P |
| 元件分類(lèi)： | 運(yùn)動(dòng)控制電子 |
| 英文描述： | Wideband, High Gain VOLTAGE LIMITING AMPLIFIER |
| 中文描述： | 寬帶，高增益電壓限幅放大器 |
| 文件頁(yè)數(shù)： | 14/16頁(yè) |
| 文件大?。?/td> | 175K |
| 代理商： | OPA689P |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)當(dāng)前第14頁(yè)第15頁(yè)第16頁(yè)
14
OPA689
ESD PROTECTION
ESD damage is known to damage MOSFET devices, but any
semiconductor device is vulnerable to ESD damage. This is
particularly true for very high speed, fine geometry processes.
ESD damage can cause subtle changes in amplifier input
characteristics without necessarily destroying the device. In
precision operational amplifiers, this may cause a noticeable
degradation of offset voltage and drift. Therefore, ESD
handling precautions are required when handling the OPA689.
OUTPUT LIMITERS
The output voltage is linearly dependent on the input(s)
when it is between the limiter voltages V
H
(pin 8) and V
L
(pin 5). When the output tries to exceed V
H
or V
L
, the
corresponding limiter buffer takes control of the output
voltage and holds it at V
H
or V
L
.
Because the limiters act on the output, their accuracy does
not change with gain. The transition from the linear region
of operation to output limiting is sharp—the desired output
signal can safely come to within 30mV of V
H
or V
L
.
Distortion performance is also good over the same range.
The limiter voltages can be set to within 0.7V of the supplies
(V
L
≥
–V
S
+ 0.7V, V
H
≤
+V
S
– 0.7V). They must also be at
least 200mV apart (V
H
– V
L
≥
0.2V).
When pins 5 and 8 are left open, V
H
and V
L
go to the Default
Voltage Limit; the minimum values are in the spec table.
Looking at Figure 7 for the zero bias current case will show
the expected range of (V
S
– default limit voltages) = head-
room).
When the limiter voltages are more than 2.1V from the
supplies (V
L
≥
–V
S
+ 2.1V or V
H
≤
+V
S
– 2.1V), you can
use simple resistor dividers to set V
H
and V
L
(see Figure 1).
Make sure you include the Limiter Input Bias Currents
(Figure 7) in the calculations (i.e., I
VL
≈
–50
μ
A out of pin
5, and I
VH
≈
+50
μ
A out of pin 8). For good limiter voltage
accuracy, run at least 1mA quiescent bias current through
these resistors.
When the limiter voltages need to be within 2.1V of the
supplies (V
L
≤
–V
S
+ 2.1V or V
H
≥
+V
S
– 2.1V), use low
impedance voltage sources to set V
H
and V
L
to minimize
errors due to bias current uncertainty. This will typically be
the case for single supply operation (V
S
= +5V). Figure 2
runs 2.5mA through the resistive divider that sets V
H
and
V
L
. This keeps errors due to I
VH
and I
VL
<
±
1% of the target
limit voltages.
The limiters’ DC accuracy depends on attention to detail.
The two dominant error sources can be improved as follows:
Power supplies, when used to drive resistive dividers that
set V
H
and V
L
, can contribute large errors (e.g., (5%).
Using a more accurate source, or bypassing pins 5 and 8
with good capacitors, will improve limiter PSRR.
The resistor tolerances in the resistive divider can also
dominate. Use 1% resistors.
Other error sources also contribute, but should have little
impact on the limiters’ DC accuracy:
Reduce offsets caused by the Limiter Input Bias Currents.
Select the resistors in the resistive divider(s) as described
above.
Consider the signal path DC errors as contributing to the
uncertainty in the useable output range.
The Limiter Offset Voltage only slightly degrades the
limiter accuracy.
Figure 8 shows how the limiters affect distortion perfor-
mance. Virtually no degradation in linearity is observed for
output voltages swinging right up to the limiter voltages.
FIGURE 8. Linearity Guardband.
FIGURE 7. Limiter Bias Current vs Limiter Voltage.
HARMONIC DISTORTION NEAR LIMIT VOLTAGES
–40
–45
–50
–55
–60
–65
–70
–75
–80
–85
–90
± Limit Voltage (V)
0.9
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2
V
O
= 0V
±1Vp
f
1
= 5MHz
R
L
= 500
HD2
HD3
100
75
50
25
0
–25
–50
–75
–100
LIMITER INPUT BIAS CURRENT vs BIAS VOLTAGE
Limiter Headroom (V)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
L
μ
A
Maximum Over Temperature
Minimum Over Temperature
Limiter Headroom = +V
S
– V
H
Current = I
VH
or –I
VL
= V
L
– (–V
S
)
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| OPA689 | Wideband, High Gain VOLTAGE LIMITING AMPLIFIER |
| OPA693ID | Ultra-Wideband, Fixed Gain Video BUFFER AMPLIFIER with Disable |
| OPA693IDR | Ultra-Wideband, Fixed Gain Video BUFFER AMPLIFIER with Disable |
| OPA693 | Ultra-Wideband, Fixed Gain Video BUFFER AMPLIFIER with Disable |
| OPA693IDBVR | Ultra-Wideband, Fixed Gain Video BUFFER AMPLIFIER with Disable |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| OPA689U | 制造商:BB 制造商全稱(chēng):BB 功能描述:EVALUATION FIXTURE |
| OPA689U/2K5 | 制造商:Rochester Electronics LLC 功能描述:OP AMP WIDEBAND VOLT LIMITING - Bulk 制造商:Texas Instruments 功能描述: |
| OPA690 | 制造商:BB 制造商全稱(chēng):BB 功能描述:Low-Power, Single-Supply, Wideband Operational Amplifier |
| OPA690ID | 功能描述:高速運(yùn)算放大器 Wideband Voltage Feeback RoHS:否 制造商:Texas Instruments 通道數(shù)量:1 電壓增益 dB:116 dB 輸入補(bǔ)償電壓:0.5 mV 轉(zhuǎn)換速度:55 V/us 工作電源電壓:36 V 電源電流:7.5 mA 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube |
| OPA690ID | 制造商:Texas Instruments 功能描述:IC SM OP-AMP WIDEBAND VFB |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。