- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄363774 > OPA4727 20MHz, High Precision CMOS Operational Amplifier PDF資料下載
參數(shù)資料
| 型號(hào)： | OPA4727 |
| 英文描述： | 20MHz, High Precision CMOS Operational Amplifier |
| 中文描述： | 為20MHz，高精度CMOS運(yùn)算放大器 |
| 文件頁數(shù)： | 12/20頁 |
| 文件大小： | 537K |
| 代理商： | OPA4727 |
"#"$
%"#"$
#"#"
"#&
SBOS314B SEPTEMBER 2004 REVISED DECEMBER 2004
www.ti.com
12
RAIL-TO-RAIL OUTPUT
A class AB output stage with common-source transistors
is used to achieve rail-to-rail output. This output stage is
capable of driving heavy loads connected to any point
between V+ and V. For light resistive loads ( > 100k
),
the output voltage can swing to 150mV from the supply rail,
while still maintaining excellent linearity (A
OL
> 110dB).
With 1k
resistive loads, the output is specified to swing
to within 250mV from the supply rails with excellent
linearity (see the Typical Characteristics curve,
Output
Voltage Swing vs Output Current
).
CAPACITIVE LOAD AND STABILITY
Capacitive load drive is dependent upon gain and the
overshoot requirements of the application. Increasing the
gain enhances the ability of the amplifier to drive greater
capacitive loads (see the Typical Characteristics curve,
Small-Signal Overshoot vs Capacitive Load
).
One method of improving capacitive load drive in the
unity-gain configuration is to insert a 10
to 20
resistor
inside the feedback loop, as shown in Figure 3. This
reduces ringing with large capacitive loads while
maintaining DC accuracy.
R
S
20
OPA727
C
L
R
L
V
IN
V
OUT
V+
Figure 3. Series Resistor in Unity-Gain Buffer
Configuration Improves Capacitive Load Drive
DRIVING FAST 16-BIT ADCs
The OPA727 series is optimized for driving fast 16-bit
ADCs such as the ADS8342. The OPA727 op amps buffer
the converter input capacitance and resulting charge
injection, while providing signal gain. Figure 4 shows the
OPA727 in a single-ended method of interfacing to the
ADS8342 16-bit, 250kSPS, 4-channel ADC with an input
range of
±
2.5V. The OPA727 has demonstrated excellent
settling time to the 16-bit level within the 600ns acquisition
time of the ADS8342. The RC filter, shown in Figure 4, has
been carefully tuned for best noise and settling
performance. It may need to be adjusted for different op
amp configurations. Please refer to the ADS8342 data
sheet (available for download at www.ti.com) for additional
information on this product.
75
OPA727
ADS8342
16Bit ADC
AIN
Common
330pF
V
IN
±
2.5V
+5V
5V
+5V
5V
Figure 4. OPA727 Driving an ADC
TRANSIMPEDANCE AMPLIFIER
Wide bandwidth, low input bias current, and low input
voltage and current noise make the OPA727 an ideal
wideband photodiode transimpedance amplifier. Low-
voltage noise is important because photodiode capaci-
tance causes the effective noise gain of the circuit to
increase at high frequency.
The key elements to a transimpedance design, as shown
in Figure 5, are the expected diode capacitance (C
D
),
which should include the parasitic input common-mode
and differential-mode input capacitance (4pF + 5pF for the
OPA727); the desired transimpedance gain (R
F
); and the
GBW for the OPA727 (20MHz). With these three variables
set, the feedback capacitor value (C
F
) can be set to control
the frequency response. C
F
includes the stray capacitance
of R
F
, which is 0.2pF for a typical surface-mount resistor.
OPA727
V
OUT
10M
+5V
5V
C
D
R
F
C
F(1)
< 1pF
λ
NOTE: (1) C
is optional to prevent gain peaking.
It includes the stray capacitance of R
F
.
Figure 5. Dual-Supply Transimpedance Amplifier
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| OPA727 | 20MHz, High Precision CMOS Operational Amplifier |
| OPA728 | 20MHz, High Precision CMOS Operational Amplifier |
| OPA2734 | CEC/I2C-bus translator, SOT360-1 (TSSOP20), Reel Dry Pack, SMD, 13" |
| OPA2734AIDGSRG4 | HDMI transmitter up to 150 MHz pixel rate with 3 x 8-bit video inputs and 4 x I2S-bus with S/PDIF, SOT315-1 (LQFP80), Tray Dry Pack, Bakeable, Multiple |
| OPA2734AIDGSTG4 | Single Audio Amplifier |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| OPA4727AIPW | 功能描述:運(yùn)算放大器 - 運(yùn)放 20MHz High Prec CMOS Op Amp RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補(bǔ)償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| OPA4727AIPWG4 | 功能描述:運(yùn)算放大器 - 運(yùn)放 20MHz High Prec CMOS Op Amp RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補(bǔ)償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| OPA4727AIPWR | 功能描述:運(yùn)算放大器 - 運(yùn)放 etrim 20MHz Hi Precisin CMOS Op Amp RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補(bǔ)償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| OPA4727AIPWRG4 | 功能描述:運(yùn)算放大器 - 運(yùn)放 e-trim(TM) 20MHz Hi Prec CMOS Op Amp RoHS:否 制造商:STMicroelectronics 通道數(shù)量:4 共模抑制比（最小值）:63 dB 輸入補(bǔ)償電壓:1 mV 輸入偏流（最大值）:10 pA 工作電源電壓:2.7 V to 5.5 V 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-16 轉(zhuǎn)換速度:0.89 V/us 關(guān)閉:No 輸出電流:55 mA 最大工作溫度:+ 125 C 封裝:Reel |
| OPA4743 | 制造商:BB 制造商全稱:BB 功能描述:12V, 7MHz, CMOS, Rail-to-Rail I/O OPERATIONAL AMPLIFIERS |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。