參數(shù)資料
型號(hào): AD8625AR-REEL
廠商: Analog Devices Inc
文件頁(yè)數(shù): 7/20頁(yè)
文件大?。?/td> 0K
描述: IC OPAMP JFET 5MHZ QUAD 14SOIC
產(chǎn)品變化通告: Product Discontinuance 27/Oct/2011
標(biāo)準(zhǔn)包裝: 2,500
放大器類(lèi)型: J-FET
電路數(shù): 4
輸出類(lèi)型: 滿擺幅
轉(zhuǎn)換速率: 5 V/µs
增益帶寬積: 5MHz
電流 - 輸入偏壓: 0.25pA
電壓 - 輸入偏移: 350µV
電流 - 電源: 710µA
電流 - 輸出 / 通道: 15mA
電壓 - 電源,單路/雙路(±): 5 V ~ 26 V,±2.5 V ~ 13 V
工作溫度: -40°C ~ 85°C
安裝類(lèi)型: 表面貼裝
封裝/外殼: 14-SOIC(0.154",3.90mm 寬)
供應(yīng)商設(shè)備封裝: 14-SOIC
包裝: 帶卷 (TR)
Data Sheet
AD8625/AD8626/AD8627
Rev. F | Page 15 of 20
MINIMIZING INPUT CURRENT
The AD862x is guaranteed to 1 pA maximum input current
with a ±13 V supply voltage at room temperature. Careful
attention to how the amplifier is used maintains or possibly
betters this performance. The amplifier’s operating temperature
should be kept as low as possible. Like other JFET input ampli-
fiers, the AD862x’s input current doubles for every 10°C rise in
junction temperature, as illustrated in Figure 8. On-chip power
dissipation raises the device operating temperature, causing an
increase in input current. Reducing supply voltage to cut power
dissipation reduces the AD862x’s input current. Heavy output
loads can also increase chip temperature; maintaining a
minimum load resistance of 1 k is recommended.
The AD862x is designed for mounting on PC boards. Main-
taining picoampere resolution in those environments requires
a lot of care. Both the board and the amplifier’s package have
finite resistance. Voltage differences between the input pins and
other pins, as well as PC board metal traces may cause parasitic
currents larger than the AD862x’s input current, unless special
precautions are taken. To ensure the best result, refer to the ADI
website for proper board layout seminar materials. Two
common methods of minimizing parasitic leakages that should
be used are guarding of the input lines and maintaining
adequate insulation resistance.
Contaminants, such as solder flux on the board’s surface and
the amplifier’s package, can greatly reduce the insulation
resistance between the input pin and traces with supply or
signal voltages. Both the package and the board must be kept
clean and dry.
PHOTODIODE PREAMPLIFIER APPLICATION
The low input current and offset voltage levels of the AD862x,
together with its low voltage noise, make this amplifier an
excellent choice for preamplifiers used in sensitive photodiode
applications. In a typical photovoltaic preamp circuit, shown in
Figure 45, the output of the amplifier is equal to
f
p
f
OUT
(P)R
R
)
ID(R
V
=
=
where:
ID = photodiode signal current (A).
Rp = photodiode sensitivity (A/W).
Rf = value of the feedback resistor, in .
P = light power incident to photodiode surface, in W.
The amplifier’s input current, IB, contributes an output voltage
error proportional to the value of the feedback resistor. The
offset voltage error, VOS, causes a small current error due to the
photodiode’s finite shunt resistance, RD.
The resulting output voltage error, VE, is equal to
)
(I
R
V
R
V
B
f
OS
D
f
E
+
+
= 1
A shunt resistance on the order of 100 M is typical for a small
photodiode. Resistance RD is a junction resistance that typically
drops by a factor of two for every 10°C rise in temperature. In
the AD862x, both the offset voltage and drift are low, which
helps minimize these errors. With IB values of 1 pA and VOS of
50 mV, VE for Figure 45 is very negligible. Also, the circuit in
Figure 45 results in an SNR value of 95 dB for a signal bandwidth
of 30 kHz.
03023-044
RD
100M
C4
15pF
IB
VOS
CF
5pF
RF
1.5M
OUTPUT
AD8627
PHOTODIODE
Figure 45. A Photodiode Model Showing DC Error
相關(guān)PDF資料
PDF描述
0034.1515 FUSE 800MA 250V 5X20 FAST GLASS
0034.1517 FUSE 1.25A 250V 5X20 FAST GLASS
SD12T1 TVS ZENER 350W 12V ESD SOD323
3412.0123.26 FUSE 4A 32V 0603 FAST
3412.0122.26 FUSE 3.5A 32V 0603 FAST
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AD8625AR-REEL7 功能描述:IC OPAMP JFET 5MHZ QUAD 14SOIC RoHS:否 類(lèi)別:集成電路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 放大器類(lèi)型:通用 電路數(shù):1 輸出類(lèi)型:滿擺幅 轉(zhuǎn)換速率:0.11 V/µs 增益帶寬積:350kHz -3db帶寬:- 電流 - 輸入偏壓:4nA 電壓 - 輸入偏移:20µV 電流 - 電源:260µA 電流 - 輸出 / 通道:20mA 電壓 - 電源,單路/雙路(±):2.7 V ~ 36 V,±1.35 V ~ 18 V 工作溫度:-40°C ~ 85°C 安裝類(lèi)型:表面貼裝 封裝/外殼:8-SOIC(0.154",3.90mm 寬) 供應(yīng)商設(shè)備封裝:8-SO 包裝:帶卷 (TR)
AD8625ARU 制造商:Analog Devices 功能描述:OP Amp Quad GP R-R O/P 制造商:Analog Devices 功能描述:OP Amp Quad GP R-R O/P ±13V/26V 14-Pin TSSOP
AD8625ARU-REEL 制造商:Analog Devices 功能描述:OP Amp Quad GP R-R O/P 制造商:Analog Devices 功能描述:OP Amp Quad GP R-R O/P ±13V/26V 14-Pin TSSOP T/R 制造商:Rochester Electronics LLC 功能描述:QUAD PRECISION SINGLE SUPPLY DI-JFET AMP - Tape and Reel
AD8625ARUZ 功能描述:IC OPAMP JFET 5MHZ QUAD 14TSSOP RoHS:是 類(lèi)別:集成電路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 放大器類(lèi)型:通用 電路數(shù):4 輸出類(lèi)型:- 轉(zhuǎn)換速率:0.6 V/µs 增益帶寬積:1MHz -3db帶寬:- 電流 - 輸入偏壓:45nA 電壓 - 輸入偏移:2000µV 電流 - 電源:1.4mA 電流 - 輸出 / 通道:40mA 電壓 - 電源,單路/雙路(±):3 V ~ 32 V,±1.5 V ~ 16 V 工作溫度:0°C ~ 70°C 安裝類(lèi)型:表面貼裝 封裝/外殼:14-TSSOP(0.173",4.40mm 寬) 供應(yīng)商設(shè)備封裝:14-TSSOP 包裝:帶卷 (TR) 其它名稱(chēng):LM324ADTBR2G-NDLM324ADTBR2GOSTR
AD8625ARUZ 制造商:Analog Devices 功能描述:OP-AMP, PRECISION, 5MHZ, 5V/us, TSSOP-14