FEATURES
Single-supply operation: 2.7 V to 5.5 V Low supply current: 45 μA/amplifier Wide bandwidth: 1 MHz No phase reversal
Low input currents: 4 pA Unity gain stable
Rail-to-rail input and output
APPLICATIONS
ASIC input or output amplifiers Sensor interfaces
Piezoelectric transducer amplifiers Medical instrumentations Mobile communications Audio outputs Portable systems
GENERAL DESCRIPTION
The AD8541/AD8542/AD8544 are single, dual, and quad rail-to-rail input and output single-supply amplifiers featuring very low supply current and 1 MHz bandwidth. All are guaranteed to operate from a 2.7 V single supply as well as a 5 V supply. These parts provide 1 MHz bandwidth at a low current consumption of 45 μA per amplifier.
Very low input bias currents enable the AD8541/AD8542/AD8544 to be used for integrators, photodiode amplifiers, piezoelectric sensors, and other applications with high source impedance. The supply current is only 45 μA per amplifier, ideal for battery operation.
Rail-to-rail inputs and outputs are useful to designers buffering ASICs in single-supply systems. The AD8541/AD8542/AD8544 are optimized to maintain high gains at lower supply voltages, making them useful for active filters and gain stages.
The AD8541/AD8542/AD8544 are specified over the extended industrial temperature range (–40°C to +125°C). The AD8541 is available in 8-lead SOIC, 5-lead SC70, and 5-lead SOT-23 packages. The AD8542 is available in 8-lead SOIC, 8-lead MSOP, and 8-lead TSSOP surface-mount packages. The AD8544 is available in 14-lead narrow SOIC and 14-lead TSSOP surface-mount packages. All MSOP, SC70, and SOT versions are available in tape and reel only.
Rev. E
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners.
General-Purpose CMOS Rail-to-Rail AmplifiersAD8541/AD8542/AD8544
PIN CONFIGURATIONS
OUT A1AD85415V+V–21+IN A034–IN A0-53900
Figure 1. 5-Lead SC70 and 5-Lead SOT-23
(KS and RJ Suffixes)
NC1AD85418NC–IN A27V++IN A36OUTAV–45NC200-53NC = NO CONNECT900
Figure 2. 8-Lead SOIC
(R Suffix)
OUT A1AD85428V+–IN A27OUT B+IN A36–IN B3V–450+IN B0-53900
Figure 3. 8-Lead SOIC, 8-Lead MSOP, and 8-Lead TSSOP
(R, RM, and RU Suffixes)
OUT A1142133124AD854411+IN B510–IN B694OUT B7800-53900
Figure 4. 14-Lead SOIC and 14-Lead TSSOP
(R and RU Suffixes)
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved.
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AD8541/AD8542/AD8544
Typical Performance Characteristics..............................................7 Theory of Operation......................................................................12 Notes on the AD854x Amplifiers.............................................12 Applications.....................................................................................13 Notch Filter.................................................................................13 Comparator Function................................................................13 Photodiode Application............................................................14 Outline Dimensions.......................................................................15 Ordering Guide..........................................................................17
TABLE OF CONTENTS
Features..............................................................................................1 Applications.......................................................................................1 General Description.........................................................................1 Pin Configurations...........................................................................1 Revision History...............................................................................2 Specifications.....................................................................................3 Electrical Characteristics.............................................................3 Absolute Maximum Ratings............................................................6 Thermal Resistance......................................................................6 ESD Caution..................................................................................6
REVISION HISTORY
1/07—Rev. D to Rev. E
Updated Format..................................................................Universal Changes to Photodiode Application Section..............................14 Changes to Ordering Guide..........................................................17 8/04—Rev. C to Rev. D
Changes to Ordering Guide............................................................5 Changes to Figure 3........................................................................10 Updated Outline Dimensions.......................................................12 1/03—Rev. B to Rev. C
Updated Format..................................................................Universal Changes to General Description....................................................1 Changes to Ordering Guide............................................................5 Changes to Outline Dimensions...................................................12
Rev. E | Page 2 of 20
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I
AD8541/AD8542/AD8544
I
SPECIFICATIONS
ELECTRICAL CHARACTERISTICS
VS = 2.7 V, VCM = 1.35 V, TA = 25°C, unless otherwise noted.
IParameter Symbol NPUT CHARACTERSTCS
Table 1.
Conditions
Min Typ Max Unit 1 4 0.1 45 500 4 100 2000 25 2.65 35 15 ±20 50
6 7 60 100 1000 30 50 500 2.7 100 125
mV mV pA pA pA pA pA pA V dB dB V/mV V/mV V/mV μV/°C fA/°C fA/°C fA/°C V V mV mV mA mA Ω
I
Offset Voltage VOS –40°C ≤ TA ≤ +125°C
II
Input Bias Current IB –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Input Offset Current IOS –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Input Voltage Range 0 Common-Mode Rejection Ratio CMRR VCM = 0 V to 2.7 V 40 –40°C ≤ TA ≤ +125°C 38 Large Signal Voltage Gain AVO RL = 100 kΩ , VO = 0.5 V to 2.2 V 100 –40°C ≤ TA ≤ +85°C 50 –40°C ≤ TA ≤ +125°C 2 Offset Voltage Drift ΔVOS/ΔT –40°C ≤ TA ≤ +125°C
II
Bias Current Drift ΔIB/ΔT –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Offset Current Drift ΔIOS/ΔT –40°C ≤ TA ≤ +125°C OUTPUT CHARACTERSTCS
Output Voltage High VOH IL = 1 mA 2.575 –40°C ≤ TA ≤ +125°C 2.550 Output Voltage Low VOL IL = 1 mA –40°C ≤ TA ≤ +125°C Output Current IOUT VOUT = VS – 1 V ±SC Closed-Loop Output Impedance ZOUT f = 200 kHz, AV = 1
POWER SUPPLY Power Supply Rejection Ratio PSRR VS = 2.5 V to 6 V 65 76 dB –40°C ≤ TA ≤ +125°C 60 dB Supply Current/Amplifier ISY VO = 0 V 38 55 μA –40°C ≤ TA ≤ +125°C 75 μA DYNAMC PERFORMANCE Slew Rate SR RL = 100 kΩ 0.4 0.75 V/μs Settling Time tS To 0.1% (1 V step) 5 μs Gain Bandwidth Product GBP 980 kHz Phase Margin Φo 63 Degrees NOSE PERFORMANCE Voltage Noise Density
Current Noise Density
en en in
f = 1 kHz f = 10 kHz
40 38 <0.1
nV/√Hz nV/√Hz pA/√Hz
Rev. E | Page 3 of 20
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AD8541/AD8542/AD8544
IVS = 3.0 V, VCM = 1.5 V, TA = 25°C, unless otherwise noted.
Table 2.
Parameter Symbol Conditions Min Typ Max Unit
INPUT CHARACTERSTCS Offset Voltage VOS 1 6 mV –40°C ≤ TA ≤ +125°C 7 mV Input Bias Current IB 4 60 pA –40°C ≤ TA ≤ +85°C 100 pA I –40°C ≤ TA ≤ +125°C 1000 pA Input Offset Current IOS 0.1 30 pA –40°C ≤ TA ≤ +85°C 50 pA –40°C ≤ TA ≤ +125°C 500 pA IIInput Voltage Range 0 3 V Common-Mode Rejection Ratio CMRR VCM = 0 V to 3 V 40 45 dB –40°C ≤ TA ≤ +125°C 38 dB Large Signal Voltage Gain AVO RL = 100 kΩ , VO = 0.5 V to 2.2 V 100 500 V/mV –40°C ≤ TA ≤ +85°C 50 V/mV –40°C ≤ TA ≤ +125°C 2 V/mV Offset Voltage Drift ΔVOS/ΔT –40°C ≤ TA ≤ +125°C 4 μV/°C Bias Current Drift ΔIB/ΔT –40°C ≤ TA ≤ +85°C 100 fA/°C –40°C ≤ TA ≤ +125°C 2000 fA/°C Offset Current Drift ΔIOS/ΔT –40°C ≤ TA ≤ +125°C 25 fA/°C OUTPUT CHARACTERSTCS Output Voltage High VOH IL = 1 mA 2.875 2.955 V
I II–40°C ≤ TA ≤ +125°C 2.850 V
Output Voltage Low VOL IL = 1 mA 32 100 mV –40°C ≤ TA ≤ +125°C 125 mV Output Current IOUT VOUT = VS – 1 V 18 mA ±SC ±25 mA Closed-Loop Output Impedance ZOUT f = 200 kHz, AV = 1 50 Ω POWER SUPPLY Power Supply Rejection Ratio PSRR VS = 2.5 V to 6 V 65 76 dB –40°C ≤ TA ≤ +125°C 60 dB Supply Current/Amplifier ISY VO = 0 V 40 60 μA –40°C ≤ TA ≤ +125°C 75 μA DYNAMC PERFORMANCE Slew Rate SR RL = 100 kΩ 0.4 0.8 V/μs Settling Time tS To 0.01% (1 V step) 5 μs Gain Bandwidth Product GBP 980 kHz Phase Margin Φo 64 Degrees NOSE PERFORMANCE Voltage Noise Density en f = 1 kHz 42 nV/√Hz en f = 10 kHz 38 nV/√Hz Current Noise Density in <0.1 pA/√Hz
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AD8541/AD8542/AD8544
VS = 5.0 V, VCM = 2.5 V, TA = 25°C, unless otherwise noted. Table 3.
Parameter
INPUT CHARACTERISTICS
Symbol
Conditions
Min
Typ 1 4 0.1 48 40 4 100 2000 25 4.965 25 30 ±60 45
Max 6 7 60 100 1000 30 50 500 5 100 125
Unit mV mV pA pA pA pA pA pA V dB dB V/mV V/mV V/mV μV/°C fA/°C fA/°C fA/°C V V mV mV mA mA Ω
Offset Voltage VOS –40°C ≤ TA ≤ +125°C Input Bias Current IB I –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Input Offset Current IOS –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Input Voltage Range 0 Common-Mode Rejection Ratio CMRR VCM = 0 V to 5 V 40 –40°C ≤ TA ≤ +125°C 38 Large Signal Voltage Gain AVO RL = 100 kΩ , VO = 0.5 V to 2.2 V 20 –40°C ≤ TA ≤ +85°C 10 –40°C ≤ TA ≤ +125°C 2 Offset Voltage Drift ΔVOS/ΔT –40°C ≤ TA ≤ +125°C Bias Current Drift ΔIB/ΔT –40°C ≤ TA ≤ +85°C –40°C ≤ TA ≤ +125°C Offset Current Drift ΔIOS/ΔT –40°C ≤ TA ≤ +125°C OUTPUT CHARACTERISTICS
Output Voltage High VOH IL = 1 mA 4.9 –40°C ≤ TA ≤ +125°C 4.875 Output Voltage Low VOL IL = 1 mA –40°C ≤ TA ≤ +125°C Output Current IOUT VOUT = VS – 1 V ±SC Closed-Loop Output Impedance ZOUT f = 200 kHz, AV = 1
POWER SUPPLY Power Supply Rejection Ratio PSRR VS = 2.5 V to 6 V 65 76 dB –40°C ≤ TA ≤ +125°C 60 dB Supply Current/Amplifier ISY VO = 0 V 45 65 μA –40°C ≤ TA ≤ +125°C 85 μA DYNAMIC PERFORMANCE Slew Rate
Full-Power Bandwidth Settling Time
Gain Bandwidth Product Phase Margin NOISE PERFORMANCE Voltage Noise Density
Current Noise Density
SR BWP tS GBP Φo en en in
RL = 100 kΩ, CL = 200 pF 1% distortion To 0.1% (1 V step)
f = 1 kHz f = 10 kHz
0.45
0.92 70 6 1000 67 42 38 <0.1
V/μs kHz μs kHz Degrees
nV/√Hz nV/√Hz pA/√Hz
Rev. E | Page 5 of 20
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AD8541/AD8542/AD8544
THERMAL RESISTANCE
ABSOLUTE MAXIMUM RATINGS
Table 4.
θJA is specified for the worst-case conditions, that is, a device Parameter Rating soldered in a circuit board for surface-mount packages. Supply Voltage (VS) 6 V
Input Voltage GND to VS
Table 5. 1
Differential Input Voltage ±6 V Package Type θJA θJC Unit
Storage Temperature Range −65°C to +150°C
5-Lead SC70 (KS) 376 126 °C/W
Operating Temperature Range −40°C to +125°C
5-Lead SOT-23 (RJ) 230 146 °C/W
Junction Temperature Range −65°C to +150°C
8-Lead SOIC (R) 158 43 °C/W
Lead Temperature (Soldering, 60 sec) 300°C
8-Lead MSOP (RM) 210 45 °C/W
18-Lead TSSOP (RU) 240 43 °C/W For supplies less than 6 V, the differential input voltage is equal to ±VS.
14-Lead SOIC (R) 120 36 °C/W
Stresses above those listed under Absolute Maximum Ratings
14-Lead TSSOP (RU) 240 43 °C/W may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ESD CAUTION
Rev. E | Page 6 of 20
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AD8541/AD8542/AD8544
TYPICAL PERFORMANCE CHARACTERISTICS
1801601401201008060402000935-005400VS=5VVCM=2.5VTA=25°CINPUT BIAS CURRENT (pA)35030025020015010050VS = 2.7V AND 5VVCM = VS/2NUMBER OF AMPLIFIERS–3.5–2.5–1.5–0.50.51.52.5INPUT OFFSETVOLTAGE(mV)3.54.5–200
20406080TEMPERATURE (°C)10012014000935-0080–4.50–40
Figure 5. Input Offset Voltage Distribution
1.00.5INPUT OFFSET VOLTAGE (mV)7Figure 8. Input Bias Current vs. Temperature
VS = 2.7V AND 5VVCM = VS/26VS = 2.7V AND 5VVCM = VS/2INPUT OFFSET CURRENT (pA)00935-0060–0.5–1.0–1.5–2.0–2.5–3.0–3.5–4.0–55–35–155
25456585TEMPERATURE (°C)
105
125
54321000935-009145–1–55–35–155
25456585TEMPERATURE (°C)105125145
Figure 6. Input Offset Voltage vs. Temperature Figure 9. Input Offset Current vs. Temperature
98INPUT BIAS CURRENT (pA)VS = 2.7V AND 5VVCM = VS/2POWER SUPPLY REJECTION (dB)1601401201008060
+PSRR40200–20
00935-007VS = 2.7VTA = 25°C76543210–0.5–PSRR0.51.52.53.5COMMON-MODE VOLTAGE (V)4.55.51k
10k100kFREQUENCY (Hz)
1M10M00935-010–40100
Figure 7. Input Bias Current vs. Common-Mode Voltage
Figure 10. Power Supply Rejection Ratio vs. Frequency
Rev. E | Page 7 of 20
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AD8541/AD8542/AD8544
10kVS = 2.7VTA = 25°CSMALL SIGNAL OVERSHOOT (%)5060VS = 2.7VRL = 10kΩTA = 25°C+OS
1kΔ OUTPUT VOLTAGE (mV)100SOURCE10SINK4030–OS1200.1100.010.11LOAD CURRENT (mA)1010010
1001kCAPACITANCE (pF)10k00935-01400935-01500935-01600935-0110.010.0010
Figure 11. Output Voltage to Supply Rail vs. Load Current
3.0Figure 14. Small Signal Overshoot vs. Load Capacitance
60VS = 2.7VRL = 2kΩTA = 25°CSMALL SIGNAL OVERSHOOT (%)2.5VS = 2.7VVIN = 2.5V p-pRL = 2kΩTA = 25°C50OUTPUT SWING (V p-p)2.040+OS1.530–OS1.0200.5101k10k100kFREQUENCY (Hz)1M10M00935-0120010
1001kCAPACITANCE (pF)10k
Figure 12. Closed-Loop Output Voltage Swing vs. Frequency
60VS = 2.7VRL =∞TA = 25°C+OSFigure 15. Small Signal Overshoot vs. Load Capacitance
SMALL SIGNAL OVERSHOOT (%)50VS = 2.7VRL = 100kΩCL = 300pFAV = 1TA = 25°C4030–OS1.35V201050mV10µs101001kCAPACITANCE (pF)10k00935-0130
Figure 16. Small Signal Transient Response
Figure 13. Small Signal Overshoot vs. Load Capacitance
Rev. E | Page 8 of 20
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VS = 2.7VRL = 2kΩAV = 1TA = 25°CAD8541/AD8542/AD8544
9080COMMON-MODE REJECTION (dB)VS = 5VTA = 25°C7060504030201001k10k100kFREQUENCY (Hz)1M10M00935-0201.35V500mV10µs00935-017
–10
Figure 17. Large Signal Transient Response
10kFigure 20. Common-Mode Rejection Ratio vs. Frequency
VS = 2.7VRL = NO LOADTA = 25°CPHASE SHIFT (Degrees)8045901351801kΔ OUTPUT VOLTAGE (mV)VS = 5VTA = 25°C100SOURCESINKGAIN (dB)60402001010.100935-0181k10k100kFREQUENCY (Hz)1M10M
0.010.11LOAD CURRENT (mA)1010000935-02100935-0220.010.001
Figure 18. Open-Loop Gain and Phase vs. Frequency
160POWER SUPPLY REJECTION RATIO (dB)Figure 21. Output Voltage to Supply Rail vs. Frequency
5.0140120VS = 5VTA = 25°C4.54.0VS = 5VVIN = 4.9V p-pRL = NO LOADTA = 25°COUTPUT SWING (V p-p)10k100kFREQUENCY (Hz)1M10M00935-019100806040200–20–401001k–PSRR+PSRR3.53.02.52.01.51.00.501k10k100kFREQUENCY (Hz)1M10M
Figure 19. Power Supply Rejection Ratio vs. Frequency Figure 22. Closed-Loop Output Voltage Swing vs. Frequency
Rev. E | Page 9 of 20
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AD8541/AD8542/AD8544
5.04.54.0
60VS = 5VVIN = 4.9V p-pRL = 2kΩTA = 25°C3.53.02.52.01.51.00.500935-023SMALL SIGNAL OVERSHOOT (%)50VS = 5VRL =∞TA = 25°COUTPUT SWING (V p-p)40+OS30–OS20101k10k100kFREQUENCY (Hz)1M10M
1001kCAPACITANCE (pF)10k00935-02600935-02700935-0280010
Figure 23. Closed-Loop Output Voltage Swing vs. Frequency Figure 26. Small Signal Overshoot vs. Load Capacitance
60VS = 5VRL = 10kΩTA = 25°CSMALL SIGNAL OVERSHOOT (%)50VS = 5VRL = 100kΩCL = 300pFAV = 1TA = 25°C40+OS30–OS202.5V1050mV101001kCAPACITANCE (pF)10k00935-02410µs0
Figure 27. Small Signal Transient Response
Figure 24. Small Signal Overshoot vs. Load Capacitance
60VS = 5VRL = 2kΩTA = 25°CSMALL SIGNAL OVERSHOOT (%)50VS = 5VRL = 2kΩAV = 1TA = 25°C40+OS30–OS202.5V101V10µs101001kCAPACITANCE (pF)10k00935-0250
Figure 28. Large Signal Transient Response
Figure 25. Small Signal Overshoot vs. Load Capacitance
Rev. E | Page 10 of 20
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VS = 5VRL = NO LOADTA = 25°CPHASE SHIFT (Degrees)5550AD8541/AD8542/AD8544
SUPPLY CURRENT/AMPLIFIER (µA)VS = 5V454080GAIN (dB)45901351806040200VS = 2.7V35302520–5500935-0291k10k100kFREQUENCY (Hz)1M10M
–35–15525456585TEMPERATURE (°C)
10512514500935-032
Figure 29. Open-Loop Gain and Phase vs. Frequency Figure 32. Supply Current per Amplifier vs. Temperature
1000900800700VS=2.7VAND5VAV=1TA=25°CVINVOUTVS = 5VRL = 10kΩAV = 1TA = 25°CIMPEDANCE (Ω)00935-0306005004003002002.5V1V20µs100
10k100k1MFREQUENCY(Hz)10M100M00935-03301k
Figure 30. No Phase Reversal
60TA = 25°CFigure 33. Closed-Loop Output Impedance vs. Frequency
SUPPLY CURRENT/AMPLIFIER (µA)50VS=5VMARKERSET@10kHzMARKERREADING:37.6nV/HzTA=25°C4030201015nV/DIV00935-031001234SUPPLY VOLTAGE (V)5605
1015FREQUENCY(kHz)
202500935-034
Figure 31. Supply Current per Amplifier vs. Supply Voltage Figure 34. Voltage Noise
Rev. E | Page 11 of 20
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AD8541/AD8542/AD8544
Sourcing and sinking are strong at lower voltages, with 15 mA available at 2.7 V and 18 mA at 3.0 V. For even higher output currents, see the Analog Devices, Inc. AD8531/AD8532/AD8534 parts, with output currents to 250 mA. Information on these parts is available from your Analog Devices representative, and data sheets are available at www.analog.com.
THEORY OF OPERATION
NOTES ON THE AD854x AMPLIFIERS
The AD8541/AD8542/AD8544 amplifiers are improved performance, general-purpose operational amplifiers.
Performance has been improved over previous amplifiers in several ways.
Lower Supply Current for 1 MHz Gain Bandwidth
The AD854x series typically uses 45 μA of current per amplifier. This is much less than the 200 μA to 700 μA used in earlier generation parts with similar performance. This makes the
AD854x series a good choice for upgrading portable designs for longer battery life. Alternatively, additional functions and performance can be added at the same current drain.
Better Performance at Lower Voltages
The AD854x family of parts was designed to provide better ac performance at 3.0 V and 2.7 V than previously available parts. Typical gain-bandwidth product is close to 1 MHz at 2.7 V. Voltage gain at 2.7 V and 3.0 V is typically 500,000. Phase margin is typically over 60°C, making the part easy to use.
Higher Output Current
At 5 V single supply, the short-circuit current is typically 60 μA. Even 1 V from the supply rail, the AD854x amplifiers can provide a 30 mA output current, sourcing or sinking.
Rev. E | Page 12 of 20
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AD8541/AD8542/AD8544
Figure 37 is an example of the AD8544 in a notch filter circuit. The frequency dependent negative resistance (FNDR) notch filter has fewer critical matching requirements than the twin-T notch and for the FNDR Q is directly proportional to a single resistor R1. While matching component values is still important, it is also much easier and/or less expensive to
accomplish in the FNDR circuit. For example, the twin-T notch uses three capacitors with two unique values, whereas the FNDR circuit uses only two capacitors, which may be of the same value. U3 is simply a buffer that is added to lower the output impedance of the circuit.
R1Q ADJUST200ΩC11µF2.5VREFR2.61kΩC21µFR2.61kΩR2.61kΩR2.61kΩ2.5VREF1312 3 4 2U111 910APPLICATIONS
NOTCH FILTER
The AD854x have very high open-loop gain (especially with a supply voltage below 4 V), which makes it useful for active
filters of all types. For example, Figure 35 illustrates the AD8542 in the classic twin-T notch filter design. The twin-T notch is desired for simplicity, low output impedance, and minimal use of op amps. In fact, this notch filter can be designed with only one op amp if Q adjustment is not required. Simply remove U2 as illustrated in Figure 36. However, a major drawback to this circuit topology is ensuring that all the Rs and Cs closely match. The components must closely match or notch frequency offset and drift causes the circuit to no longer attenuate at the ideal notch frequency. To achieve desired performance, 1% or better component tolerances or special component screens are usually required. One method to desensitize the circuit-to-component mismatch is to increase R2 with respect to R1, which lowers Q. A lower Q increases attenuation over a wider frequency range but reduces attenuation at the peak notch frequency.
5.0VR100kΩC253.6µF2.5VREFR/250kΩC26.7nFC26.7nFR22.5kΩR100kΩ 32 8U1 41/4 AD8544U3 8VOUT1/4 AD8544 11/4 AD85447U26 51/2 AD8542 1VOUT1f =2π LC1L = R2C21/4 AD8544U414NC00935-0371/2 AD8542 7U2f0 =f0 =12πRC14 1 –R1R1 + R2 5 6R197.5kΩ00935-0352.5VREF
Figure 37. FNDR 60 Hz Notch Filter with Output Buffer
2.5VREFCOMPARATOR FUNCTION
A comparator function is a common application for a spare op amp in a quad package. Figure 38 illustrates ¼ of the AD8544 as a comparator in a standard overload detection application. Unlike many op amps, the AD854x family can double as comparators because this op amp family has a rail-to-rail differential input range, rail-to-rail output, and a great speed vs. power ratio. R2 is used to introduce hysteresis. The AD854x, when used as comparators, have 5 μs propagation delay at 5 V and 5 μs overload recovery time.
R11kΩFigure 35. 60 Hz Twin-T Notch Filter, Q = 10
5.0VRR 322C 7AD8541 4 6VIN2.5VREFVOUTR/200935-036CCFigure 36. 60 Hz Twin-T Notch Filter, Q = ∞ (Ideal)
R21MΩVIN2.5VREF2.5VDCVOUT00935-0381/4 AD8541
Figure 38. AD854x Comparator Application—Overload Detector
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AD8541/AD8542/AD8544
C100pFR10MΩV+OR23D476PHOTODIODE APPLICATION
The AD854x family has very high impedance with an input bias current typically around 4 pA. This characteristic allows the AD854x op amps to be used in photodiode applications and other applications that require high input impedance. Note that the AD854x has significant voltage offset that can be removed by capacitive coupling or software calibration.
Figure 39 illustrates a photodiode or current measurement application. The feedback resistor is limited to 10 MΩ to avoid excessive output offset. Also, note that a resistor is not needed on the noninverting input to cancel bias current offset because the bias current-related output offset is not significant when compared to the voltage offset contribution. For best performance, follow the standard high impedance layout techniques, which include: • • • •
Shielding the circuit. Cleaning the circuit board.
Putting a trace connected to the noninverting input around the inverting input.
Using separate analog and digital power supplies.
VOUT
AD854100935-039
Figure 39. High Input Impedance Application—Photodiode Amplifier
2.5VREF2.5VREF
Rev. E | Page 14 of 20
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AD8541/AD8542/AD8544
5.105.004.904OUTLINE DIMENSIONS
2.90 BSC51.60 BSC1232.80 BSC4.504.404.30148PIN 10.95 BSC1.301.150.901.90BSC6.40BSC17PIN 11.051.000.800.65BSC1.20MAX0.150.050.300.191.45 MAX0.220.0810°5°0°0.600.450.300.200.090.15 MAX0.500.30SEATINGPLANESEATINGCOPLANARITYPLANE0.108°0°0.750.600.45COMPLIANT TO JEDEC STANDARDS MO-153-AB-1COMPLIANT TO JEDEC STANDARDS MO-178-AA
Figure 40. 5-Lead Small Outline Transistor Package [SOT-23]
(RJ-5)
Dimensions shown in millimeters Figure 41. 14-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-14)
Dimensions shown in millimeters
2.202.001.801.351.251.15PIN11.000.900.70512438.75 (0.3445)8.55 (0.3366)141872.402.101.804.00 (0.1575)3.80 (0.1496)6.20 (0.2441)5.80 (0.2283)0.65 BSC1.100.800.400.100.460.360.261.27 (0.0500)BSC0.25 (0.0098)0.10 (0.0039)COPLANARITY0.100.51 (0.0201)0.31 (0.0122)1.75 (0.0689)1.35 (0.0531)SEATINGPLANE0.50 (0.0197)0.25 (0.0098)8°0°0.25 (0.0098)0.17 (0.0067)1.27 (0.0500)0.40 (0.0157)45°0.10 MAX0.300.15SEATINGPLANE0.220.08 0.10 COPLANARITYCOMPLIANT TO JEDEC STANDARDS MO-203-AAFigure 42. 5-Lead Thin Shrink Small Outline Transistor Package [SC70]
(KS-5)
Dimensions shown in millimeters
Figure 43. 14-Lead Standard Small Outline Package [SOIC_N]
Narrow Body (R-14)
Dimensions shown in millimeters and (inches)
Rev. E | Page 15 of 20
060606-A
COMPLIANTTO JEDEC STANDARDS MS-012-ABCONTROLLING DIMENSIONSARE IN MILLIMETERS; INCH DIMENSIONS(INPARENTHESES)ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FORREFERENCE ONLYANDARE NOTAPPROPRIATE FOR USE IN DESIGN.元器件交易网www.cecb2b.com
AD8541/AD8542/AD8544
3.203.002.803.103.002.90
3.203.002.808515.154.904.658544.504.404.30146.40 BSCPIN 10.65 BSC0.950.850.750.150.000.380.22SEATINGPLANE1.10 MAX8°0°0.800.600.40PIN 10.65 BSC0.150.05COPLANARITY0.100.300.191.20MAXSEATING0.20PLANE0.090.230.088°0°COPLANARITY0.100.750.600.45COMPLIANT TO JEDEC STANDARDS MO-153-AA
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 45. 8-Lead Thin Shrink Small Outline Package [TSSOP]
(RU-8)
Dimensions shown in millimeters
Figure 44. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
5.00(0.1968)4.80(0.1890)4.00 (0.1574)3.80 (0.1497)81546.20 (0.2440)5.80 (0.2284)1.27 (0.0500)BSC0.25 (0.0098)0.10 (0.0040)COPLANARITY0.10SEATINGPLANE1.75 (0.0688)1.35 (0.0532)0.50 (0.0196)0.25 (0.0099)8°0°0.25 (0.0098)0.17 (0.0067)1.27 (0.0500)0.40 (0.0157)45°0.51 (0.0201)0.31 (0.0122)COMPLIANTTO JEDEC STANDARDS MS-012-AACONTROLLING DIMENSIONSARE IN MILLIMETERS; INCH DIMENSIONS(INPARENTHESES)ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FORREFERENCE ONLYANDARE NOTAPPROPRIATE FOR USE IN DESIGN.060506-A
Figure 46. 8-Lead Standard Small Outline Package [SOIC_N]
Narrow Body
(R-8)
Dimensions shown in millimeters and (inches)
Rev. E | Page 16 of 20
元器件交易网www.cecb2b.com
AD8541/AD8542/AD8544
Temperature Range –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C –40°C to +125°C
Package Description 5-Lead SC70 5-Lead SC70 5-Lead SC70 5-Lead SC70 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead SOIC_N 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead TSSOP 8-Lead TSSOP 8-Lead TSSOP 8-Lead TSSOP 14-Lead SOIC_N 14-Lead SOIC_N 14-Lead SOIC_N 14-Lead SOIC_N 14-Lead SOIC_N 14-Lead SOIC_N 14-Lead TSSOP 14-Lead TSSOP 14-Lead TSSOP 14-Lead TSSOP
Package Option KS-5 KS-5 KS-5 KS-5 R-8 R-8 R-8 R-8 R-8 R-8 RJ-5 RJ-5 RJ-5 RJ-5 RJ-5 RJ-5 R-8 R-8 R-8 R-8 R-8 R-8 RM-8 RM-8 RM-8 RM-8 RU-8 RU-8 RU-8 RU-8 R-14 R-14 R-14 R-14 R-14 R-14 RU-14 RU-14 RU-14 RU-14
Branding A4B A4B A12 A12 A4A A4A A4A A4A# A4A# A4A# AVA AVA AVA# AVA#
ORDERING GUIDE
Model
AD8541AKS-R2 AD8541AKS-REEL7 AD8541AKSZ-R21 AD8541AKSZ-REEL71 AD8541AR
AD8541AR-REEL AD8541AR-REEL7 AD8541ARZ1
AD8541ARZ-REEL1 AD8541ARZ-REEL71 AD8541ART-R2 AD8541ART-REEL AD8541ART-REEL7 AD8541ARTZ-R21 AD8541ARTZ-REEL1 AD8541ARTZ-REEL71 AD8542AR
AD8542AR-REEL AD8542AR-REEL7 AD8542ARZ1
AD8542ARZ-REEL1 AD8542ARZ-REEL71 AD8542ARM-R2 AD8542ARM-REEL AD8542ARMZ-R21 AD8542ARMZ-REEL1 AD8542ARU
AD8542ARU-REEL AD8542ARUZ1
AD8542ARUZ-REEL1 AD8544AR
AD8544AR-REEL AD8544AR-REEL7 AD8544ARZ1
AD8544ARZ-REEL1 AD8544ARZ-REEL71 AD8544ARU
AD8544ARU-REEL AD8544ARUZ1
AD8544ARUZ-REEL1
1
Z = Pb-free part; # denotes lead-free product, may be top or bottom marked.
Rev. E | Page 17 of 20
元器件交易网www.cecb2b.com
AD8541/AD8542/AD8544
NOTES
Rev. E | Page 18 of 20
元器件交易网www.cecb2b.com
AD8541/AD8542/AD8544
NOTES
Rev. E | Page 19 of 20
元器件交易网www.cecb2b.com
AD8541/AD8542/AD8544
NOTES
©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C00935-0-1/07(E)
Rev. E | Page 20 of 20
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