参数资料
型号: AD8510
厂商: Analog Devices, Inc.
英文描述: Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
中文描述: 精密,非常低噪声,低输入偏置电流,高带宽结型场效应管运算放大器
文件页数: 17/20页
文件大小: 497K
代理商: AD8510
AD8510/AD8512/AD8513
I-V CONVERSION APPLICATIONS
Photodiode Circuits
Common applications for I-V conversion include photodiode
circuits, where the amplifier is used to convert a current emitted
by a diode placed at the positive input terminal into an output
voltage.
Rev. E | Page 17 of 20
The AD8510/AD8512/AD8513’s low input bias current, wide
bandwidth, and low noise make them each an excellent choice
for various photodiode applications, including fax machines,
fiber optic controls, motion sensors, and bar code readers.
The circuit shown in Figure 53 uses a silicon diode with zero
bias voltage. This is known as a Photovoltaic Mode; this
configuration limits the overall noise and is suitable for
instrumentation applications.
4
7
3
6
2
AD8510
Cf
R2
Rd
Ct
V
EE
V
CC
0
Figure 53. Equivalent Preamplifier Photodiode Circuit
A larger signal bandwidth can be attained at the expense of
additional output noise. The total input capacitance (Ct)
consists of the sum of the diode capacitance (typically 3 pF to
4 pF) and the amplifier’s input capacitance (12 pF), which
includes external parasitic capacitance. Ct creates a pole in the
frequency response, which may lead to an unstable system. To
ensure stability and optimize the bandwidth of the signal, a
capacitor is placed in the feedback loop of the circuit shown in
Figure 53. It creates a zero and yields a bandwidth whose corner
frequency is 1/(2π(R2Cf)).
The value of
R
2 can be determined by the ratio V/I
D
, where V is
the desired output voltage of the op amp and I
D
is the diode
current. For example, if I
D
is 100 μA and a 10 V output voltage is
desired, R2 should be 100 k. Rd is a junction resistance that
drops typically by a factor of 2 for every 10°C increase in
temperature. A typical value for Rd is 1000 M. Since Rd >> R2,
the circuit behavior is not impacted by the effect of the junction
resistance. The maximum signal bandwidth is
Ct
2
R
ft
f
MAX
2
π
=
where f
t
is the unity gain frequency of the amplifier.
Using the parameters above,
Cf
≈ 1 pF, which yields a signal
bandwidth of about 2.6 MHz.
ft
R
Ct
Cf
2
2
π
=
where
ft
is the unity gain frequency of the op amp, achieves a
phase margin, Φ
m
, of approximately 45°.
A higher phase margin can be obtained by increasing the value
of
Cf
. Setting
Cf
to twice the previous value yields approximately
Φ
m
= 65° and a maximally flat frequency response, but reduces
the maximum signal bandwidth by 50%.
相关PDF资料
PDF描述
AD8510AR Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
AD8510AR-REEL Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
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AD8510ARM-REEL Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
相关代理商/技术参数
参数描述
AD8510_07 制造商:AD 制造商全称:Analog Devices 功能描述:Precision, Very Low Noise, Low Input Bias Current, Wide Bandwidth JFET Operational Amplifiers
AD8510AR 功能描述:IC OPAMP JFET 8MHZ PREC LN 8SOIC RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:1 系列:- 放大器类型:通用 电路数:4 输出类型:满摆幅 转换速率:0.6 V/µs 增益带宽积:1MHz -3db带宽:- 电流 - 输入偏压:2pA 电压 - 输入偏移:1000µV 电流 - 电源:85µA 电流 - 输出 / 通道:20mA 电压 - 电源,单路/双路(±):1.8 V ~ 6 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:14-SOIC(0.154",3.90mm 宽) 供应商设备封装:14-SOICN 包装:剪切带 (CT) 产品目录页面:680 (CN2011-ZH PDF) 其它名称:MCP6L04T-E/SLCT
AD8510ARM-R2 功能描述:IC OPAMP JFET 8MHZ PREC LN 8MSOP RoHS:否 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:2,500 系列:- 放大器类型:通用 电路数:1 输出类型:满摆幅 转换速率:0.11 V/µs 增益带宽积:350kHz -3db带宽:- 电流 - 输入偏压:4nA 电压 - 输入偏移:20µV 电流 - 电源:260µA 电流 - 输出 / 通道:20mA 电压 - 电源,单路/双路(±):2.7 V ~ 36 V,±1.35 V ~ 18 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-SOIC(0.154",3.90mm 宽) 供应商设备封装:8-SO 包装:带卷 (TR)
AD8510ARM-REEL 制造商:Analog Devices 功能描述:OP Amp Single GP 制造商:Analog Devices 功能描述:OP Amp Single GP ±15V 8-Pin MSOP T/R
AD8510ARMZ 功能描述:IC OPAMP JFET 8MHZ PREC LN 8MSOP RoHS:是 类别:集成电路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 标准包装:1,000 系列:- 放大器类型:电压反馈 电路数:4 输出类型:满摆幅 转换速率:33 V/µs 增益带宽积:20MHz -3db带宽:30MHz 电流 - 输入偏压:2nA 电压 - 输入偏移:3000µV 电流 - 电源:2.5mA 电流 - 输出 / 通道:30mA 电压 - 电源,单路/双路(±):4.5 V ~ 16.5 V,±2.25 V ~ 8.25 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-SOIC(0.154",3.90mm 宽) 供应商设备封装:14-SOIC 包装:带卷 (TR)