CN-0187 [ADI]

Crest Factor, Peak, and RMS RF Power Measurement Circuit Optimized for High Speed, Low Power, and Single 3.3 V Supply; 波峰因数,峰值和均方根RF功率测量电路优化的高速,低功耗和3.3 V单电源
CN-0187
型号: CN-0187
厂家: ADI    ADI
描述:

Crest Factor, Peak, and RMS RF Power Measurement Circuit Optimized for High Speed, Low Power, and Single 3.3 V Supply
波峰因数,峰值和均方根RF功率测量电路优化的高速,低功耗和3.3 V单电源

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Circuit Note  
CN-0187  
Devices Connected/Referenced  
ADL5502  
450 MHz to 6 GHz Crest Factor Detector  
Differential/Single-Ended Input, Dual,  
Simultaneous Sampling, 2 MSPS, 12-Bit,  
3-Channel SAR Analog-to-Digital Converter  
Circuits from the Lab™ reference circuits are engineered and  
tested for quick and easy system integration to help solve today’s  
analog, mixed-signal, and RF design challenges. For more  
information and/or support, visit www.analog.com/CN0187.  
AD7266  
Low Cost, Quad, CMOS, High Speed, Rail-to-  
Rail Amplifier  
ADA4891-4  
ADP121  
150 mA, Low Quiescent Current, CMOS Linear  
Regulator in 5-Lead TSOT or 4-Ball WLCSP  
Crest Factor, Peak, and RMS RF Power Measurement Circuit Optimized for  
High Speed, Low Power, and Single 3.3 V Supply  
EVALUATION AND DESIGN SUPPORT  
CIRCUIT FUNCTION AND BENEFITS  
Circuit Evaluation Boards  
The circuit shown in Figure 1 measures peak and rms power  
at any RF frequency from 450 MHz to 6 GHz over a range of  
approximately 45 dB. The measurement results are converted  
to differential signals in order to eliminate noise and are  
provided as digital codes at the output of a 12-bit SAR ADC  
with serial interface and integrated reference. A simple two-  
point calibration is performed in the digital domain.  
CN-0187 Circuit Evaluation Board (EVAL-CN0187-SDPZ)  
System Demonstration Platform (EVAL-SDP-CB1Z)  
Design and Integration Files  
Schematics, Layout Files, Bill of Materials  
+3.3V +3.3V  
+3.3V  
220Ω  
*SEE TEXT  
AVDD DVDD  
442Ω  
+3.3V  
8
U2-B  
U3-B  
27Ω  
*
*
1000pF 0.1µF  
U2-A  
VA1  
ENBL  
C
*
FLTR  
1
2
7
6
FLTR  
VRMS  
U6  
AD7266  
U1  
ADL5502  
0.01µF  
SDP  
BOARD  
AND  
220Ω  
220Ω  
U2-D  
VPOS  
PEAK  
*
*
VDRIVE  
0.01µF 0.01µF  
SUPPORT  
CIRCUITS  
27Ω  
+2.5V  
VA2  
D
3
5
RFIN  
RFIN  
CNTL  
CONTROL  
+1.25V  
COMM  
4
(HIGH RESET;  
LOW PEAK HOLD)  
75Ω  
A
10kΩ  
10kΩ  
CAP  
CS  
U2-C  
NOTE: U2 AND U3 ARE ADA4891-4  
0.47µF  
DOUTA  
SCLK  
0.47µF  
220Ω  
+3.3V  
442Ω  
27Ω  
+3.3V  
1µF  
+5.5V  
U3-A  
VB1  
VB2  
VIN  
VOUT  
U5  
ADP121  
EN  
1µF  
220Ω  
220Ω  
GND  
27Ω  
U3-D  
+1.25V  
+2.5V  
D
B
CAP  
AGND DGND  
0.47µF  
10kΩ  
10kΩ  
U3-C  
0.47µF  
Figure 1. High Speed, Low Power, Crest Factor, Peak, and RMS Power Measurement System (Simplified Schematic: All connections and Decoupling Not Shown)  
Rev.0  
Circuits from the Lab™ circuits from Analog Devices have been designed and built by Analog Devices  
engineers. Standard engineering practices have been employed in the design and construction of  
each circuit, andtheir function andperformance have been tested and verifiedin a lab environment at  
room temperature. However, you are solely responsible for testing the circuit and determining its  
suitability and applicability for your use and application. Accordingly, in noevent shall Analog Devices  
be liable for direct, indirect, special, incidental, consequential or punitive damages due to any cause  
whatsoever connectedtothe use ofanyCircuitsfromtheLabcircuits. (Continuedon last page)  
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.  
Tel: 781.329.4700  
Fax: 781.461.3113  
www.analog.com  
©2011 Analog Devices, Inc. All rights reserved.  
CN-0187  
Circuit Note  
The ADL5502 is a mean-responding (true rms) power detector  
in combination with an envelope detector to accurately  
determine the crest factor (CF) of a modulated signal. It can be  
used in high frequency receiver and transmitter signal chains  
from 450 MHz to 6 GHz with envelope bandwidths over 10 MHz.  
The peak-hold function allows the capture of short peaks in the  
envelope with lower sampling rate ADCs. Total current  
consumption is only 3 mA @ 3 V.  
The internal filter capacitor of the ADL5502 provides averaging  
in the square domain but leaves some residual ac on the output.  
Signals with high peak-to-average ratios, such as W-CDMA or  
CDMA2000, can produce ac residual levels on the ADL5502  
VRMS dc output. To reduce the effects of these low frequency  
components in the waveforms, some additional filtering is  
required. The internal square-domain filter capacitance of the  
ADL5502 can be augmented by connecting a CFLTR capacitor  
between Pin 1 (FLTR) and Pin 2 (VPOS). The ac residual can be  
reduced further by adding capacitance to the VRMS output.  
The combination of the internal 100 Ω output resistance and  
the added output capacitance produces a low-pass filter to  
reduce output ripple of the VRMS output (see the Selecting the  
Square-Domain Filter and Output Low-Pass Filter section of the  
ADL5502 data sheet for more details).  
The ADA4891-4 is a high speed, quad, CMOS amplifier that  
offers high performance at a low cost. Current consumption is  
only 4.4 mA/amplifier at 3 V. The amplifier features true single-  
supply capability, with an input voltage range that extends 300 mV  
below the negative rail. The rail-to-rail output stage enables  
the output to swing to within 50 mV of each rail, ensuring  
maximum dynamic range. Low distortion and fast settling time  
makes it ideal for this application.  
To measure the peak of a waveform, the control line (CNTL)  
must be temporally set to a logic high (reset mode for >1 µs)  
and then set back to a logic low (peak-hold mode). This allows  
the ADL5502 to be initialized to a known state. When setting  
the device to measure peak, peak-hold mode should be toggled  
for a period in which the input rms power and crest factor (CF)  
is not likely to change.  
The AD7266is a dual, 12-bit, high speed, low power, successive  
approximation ADC that operates from a single 2.7 V to 5.25 V  
power supply and features sampling rates up to 2 MSPS. The  
device contains two ADCs, each preceded by a 3-channel  
multiplexer, and a low noise, wide bandwidth track-and-hold  
amplifier that can handle input frequencies in excess of 30 MHz.  
Current consumption is only 3 mA at 3 V. It also contains an  
internal 2.5 V reference.  
If the ADL5502 is in peak-hold mode and the CF changes from  
high to low or the input power changes from high to low, a  
faulty peak measurement is reported. The ADL5502 simply  
keeps reporting the highest peak that occurred when the peak-  
hold mode was activated and the input power or the CF was  
high. Unless CNTL is reset, the PEAK output does not reflect  
the new peak in the signal.  
The circuit operates on a single +3.3 V supply from the  
ADP121, a low quiescent current, low dropout, linear regulator  
that operates from 2.3 V to 5.5 V and provides up to 150 mA  
of output current. The low 135 mV dropout voltage at 150 mA  
load improves efficiency and allows operation over a wide input  
voltage range. The low 30 μA of quiescent current at full load  
makes the ADP121 ideal for battery-operated portable equipment.  
The ADL5502 is capable of sourcing a VRMS output current of  
approximately 3 mA. The output current is sourced through the  
on-chip, 100 Ω series resistor; therefore, any load resistor forms  
a voltage divider with this on-chip resistance. It is  
recommended that the ADL5502 VRMS output drive high  
resistive loads to preserve output swing. If an application  
requires driving a low resistance load (as well as in cases where  
increasing the nominal conversion gain is desired), a buffering  
circuit is necessary.  
The ADP121 is available in output voltages ranging from 1.2 V  
to 3.3 V. The parts are optimized for stable operation with small  
1 μF ceramic output capacitors. The ADP121 delivers good  
transient performance with minimal board area.  
Short-circuit protection and thermal overload protection  
circuits prevent damage in adverse conditions. The ADP121 is  
available in tiny 5-lead TSOT and 4-ball, 0.4 mm pitch halide-  
free WLCSP packages and utilizes the smallest footprint  
solution to meet a variety of portable applications.  
The PEAK output is designed to drive 2 pF loads. It is  
recommended that the ADL5502 PEAK output drive low  
capacitive loads to achieve a full output response time. The  
effects of larger capacitive loads are particularly visible when  
tracking envelopes during the falling transitions. When the  
envelope is in a fall transition, the load capacitor discharges  
through the on-chip load resistance of 1.9 kΩ. If the larger  
capacitive load is unavoidable, the additional capacitance can be  
counteracted by putting a shunt resistor to ground on the PEAK  
output to allow for fast discharge. Such a shunt resistor also  
makes the ADL5502 run higher current, and it should not be  
lower than 500 Ω.  
CIRCUIT DESCRIPTION  
The RF signal being measured is applied to the ADL5502.  
A single 75 Ω termination resistor at the RF input in parallel  
with the input impedance of the ADL5502 provides a  
broadband match of 50 Ω. More precise resistive or reactive  
matches can be applied for narrow frequency band use (see  
the RF Input Interfacing section of the ADL5502 data sheet).  
Rev. 0| Page 2 of 7  
Circuit Note  
CN-0187  
Typical measured performance characteristics of the circuit are  
presented in Figure 2 through Figure 5.  
2.0  
1.8  
1.6  
1.4  
1.2  
1.0  
0.8  
0.6  
0.4  
0.2  
0
10  
1
450MHz  
900MHz  
450MHz  
900MHz  
1900MHz  
2350MHz  
2600MHz  
1900MHz  
2350MHz  
2600MHz  
0.1  
0
0.2  
0.4  
0.6  
0.8  
1.0  
INPUT (V rms)  
0.01  
–25  
–20  
–15  
–10  
–5  
0
5
10  
15  
Figure 5. Measured PEAK Output vs. Input Level (Linear Scale), 450 MHz,  
900 MHz, 1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
INPUT (dBm)  
Figure 2. Measured VRMS Output vs. Input Level (Log Scale), 450 MHz,  
900 MHz, 1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
The turn-on time and pulse response is strongly influenced by  
the size of the square-domain filter (CFLTR) and output shunt  
capacitor connected to the VRMS output. Figure 6 (taken from  
the ADL5502 data sheet) shows a plot of the output response to  
an RF pulse on the RFIN pin, with a 0.1 μF output filter  
capacitor and no square-domain filter capacitor (CFLTR). The  
falling edge is particularly dependent on the output shunt  
capacitance.  
2.0  
1.8  
1.6  
1.4  
1.2  
1.0  
450MHz  
0.8  
0.6  
0.4  
0.2  
0
900MHz  
1900MHz  
2350MHz  
2600MHz  
PULSED RFIN  
400mV rms RF INPUT  
250mV rms  
160mV rms  
0
0.2  
0.4  
0.6  
0.8  
1.0  
INPUT (V rms)  
Figure 3. Measured VRMS Output vs. Input Level (Linear Scale), 450 MHz,  
900 MHz, 1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
70mV rms  
10  
VRMS  
1ms/DIV  
Figure 6. Output Response to Various RF Input Pulse Levels, Supply3 V,  
900 MHz Frequency, Square-Domain Filter Open, Output Filter 0.1 μF  
1
To improve the falling edge of the enable and pulse responses,  
a resistor can be placed in parallel with the output shunt  
capacitor. The added resistance helps to discharge the output  
filter capacitor. Although this method reduces the power-off  
time, the added load resistor also attenuates the output (see the  
Output Drive Capability and Buffering section of the ADL5502  
data sheet). Figure 7 (taken from the ADL5502 data sheet)  
shows the improvement obtained by adding a parallel 1 kΩ  
resistor.  
450MHz  
900MHz  
1900MHz  
2350MHz  
2600MHz  
0.1  
0.01  
–25  
–20  
–15  
–10  
–5  
0
5
10  
15  
INPUT (dBm)  
Figure 4. Measured PEAK Output vs. Input Level (Log Scale), 450 MHz,  
900 MHz, 1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
Rev. 0| Page 3 of 7  
CN-0187  
Circuit Note  
PULSED RFIN  
Figure 8 and Figure 9 show plots of the VRMS and PEAK error  
at 25°C, the temperature at which the ADL5502 is calibrated.  
Note that the error is not zero; this is because the ADL5502  
does not perfectly follow the ideal linear equation, even within  
its operating region. The error at the calibration points is,  
however, equal to zero by definition.  
400mV rms RF INPUT  
250mV rms  
160mV rms  
70mV rms  
3
2
1
VRMS  
1ms/DIV  
Figure 7. Output Response to Various RF Input Pulse Levels, Supply 3 V,  
900 MHz Frequency, Square-Domain Filter Open, Output Filter 0.1 μF  
with Parallel 1 kΩ  
0
450MHz  
900MHz  
1900MHz  
2350MHz  
2600MHz  
–1  
–2  
–3  
The RMS and PEAK outputs of the ADL5502 pass through  
unity gain buffers that drive cross-coupled stages for converting  
the single-ended outputs to differential signals. The internal  
+2.5 V reference of the AD7266 (via the DCAPA and DCAPB pins)  
passes through another unity gain buffer and a voltage divider.  
This sets the common-mode voltage of the network to +1.25 V.  
–25  
–20  
–15  
–10  
–5  
0
5
10  
15  
INPUT (dBm)  
Figure 8. Measured VRMS Linearity Error vs. Input Level, 450 MHz, 900 MHz,  
1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
The AD7266 achieves simultaneous samples of the RMS and  
PEAK outputs and transfers the data within a 1 µs response  
time. The data is provided on a single serial data line. Because  
slope and intercept vary from device to device, board-level  
calibration must be performed to achieve high accuracy. In  
general, calibration is performed by applying two input power  
levels to the ADL5502 and measuring the corresponding output  
voltages. The calibration points are generally chosen to be  
within the linear operating range of the device. The best-fit line  
is characterized by calculating the conversion gain (or slope)  
and intercept using the following equations:  
3
2
1
0
450MHz  
900MHz  
1900MHz  
2350MHz  
2600MHz  
–1  
–2  
–3  
Gain = (VVRMS2 VVRMS1)/(VIN2 VIN1  
Intercept = VVRMS1 − (Gain × VIN1  
where:  
)
(1)  
(2)  
)
–25  
–20  
–15  
–10  
–5  
0
5
10  
15  
INPUT (dBm)  
V
IN is the rms input voltage to RFIN.  
VRMS is the voltage output at VRMS.  
Figure 9. Measured PEAK Linearity Error vs. Input Level, 450 MHz, 900 MHz,  
1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
V
Once gain and intercept are calculated, an equation can be  
written that allows calculation of an (unknown) input power  
based on the measured output voltage.  
When the characteristics (slope and intercept) of the VRMS and  
PEAK outputs are known, the calibration for the CF calculation  
is complete. A three-stage process must be taken to measure  
and calculate the crest factor of any waveform. First, the  
unknown signal must be applied to the RF input, and the  
corresponding VRMS level is measured. This level is indicated  
in Figure 10 as VVRMS-UNKNOWN. The RF input, VIN, is calculated  
using VVRMS-UNKNOWN and Equation 3.  
VIN = (VVRMS Intercept)/Gain  
(3)  
For an ideal (known) input power, the law conformance error of  
the measured data can be calculated as  
V
VRMS, MEASURED Intercept  
ERROR (dB) = 20× log  
(4)  
Gain×VIN, IDEAL  
Rev. 0| Page 4 of 7  
Circuit Note  
CN-0187  
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0
PEAK OF  
UNKNOWN WAVEFORM  
VRMS OF  
UNKNOWN WAVEFORM  
(RESULT INDEPENDENT  
OF WAVEFORM)  
3
V
V
PEAK-UNKNOWN  
450MHz  
900MHz  
1900MHz  
2350MHz  
2600MHz  
VRMS-UNKNOWN  
PEAK OF  
CW, CF = 0dB  
2
V
PEAK-CW  
1
0
V
INPUT (V rms)  
IN  
–0.5  
–1.0  
Figure 10. Procedure for Crest Factor Calculation  
–25  
–15  
–5  
5
15  
INPUT (dBm)  
Next, the CW reference level of PEAK, VPEAK-CW, is calculated  
using VIN (that is, the output voltage that would be seen if the  
incoming waveform was a CW signal).  
Figure 12. Measured Crest Factor of CW Signals vs. Input Level, 450 MHz,  
900 MHz, 1900 MHz, 2350 MHz, 2600 MHz, Supply +3.3 V  
V
PEAK-CW = (VIN GainPEAK) + InterceptPEAK (5)  
The performance of this or any high speed circuit is highly  
dependent on proper PCB layout. This includes, but is not  
limited to, power supply bypassing, controlled impedance lines  
(where required), component placement, signal routing, and  
power and ground planes. (See MT-031 Tutorial, MT-101 Tutorial,  
and article, A Practical Guide to High-Speed Printed-Circuit-  
Board Layout, for more detailed information regarding PCB  
layout.)  
Finally, the actual level of PEAK, VPEAK-UNKNOWN, is measured and  
the CF can be calculated as  
CF = 20 log10 (VPEAK-UNKNOWN /VPEAK-CW  
where VPEAK-CW is used as a reference point to compare  
PEAK-UNKNOWN. If both VPEAK values are equal, then the CF is 0 dB,  
as shown in Figure 11 with the CW signal (taken from the  
ADL5502 data sheet). Across the dynamic range, the calculated  
CF hovers about the 0 dB line. Likewise, for complex waveforms  
of 3 dB, 6 dB, and 9 dB CFs, the calculations accurately hover  
about the corresponding CF levels.  
)
(6)  
V
A complete design support package for this circuit note can be  
found at http://www.analog.com/CN0187-DesignSupport.  
COMMON VARIATIONS  
10  
For applications that require less RF detection range, the  
AD8363 rms detector can be used. The AD8363 has a detection  
range of 50 dB and operates at frequencies up to 6 GHz. For  
non-rms detection applications, the AD8317/AD8318/AD8319  
or ADL5513 can be used. These devices offer varying detection  
ranges and have varying input frequency ranges up to 10 GHz  
(see CN-0150 for more details).  
8-TONE WAVEFORM, 9dB CF  
9
8
7
4-TONE WAVEFORM, 6dB CF  
6
5
4
2-TONE WAVEFORM, 3dB CF  
3
2
1
CIRCUIT EVALUATION AND TEST  
This circuit uses the EVAL-CN0187-SDPZ circuit board and the  
EVAL-SDP-CB1Z System Demonstration Platform (SDP)  
evaluation board. The two boards have 120-pin mating  
connectors, allowing for the quick setup and evaluation of the  
circuit’s performance. The EVAL-CN0187-SDPZ board contains  
the circuit to be evaluated, as described in this note, and the  
SDP evaluation board is used with the CN0187 evaluation  
software to capture the data from the EVAL-CN0187-SDPZ  
circuit board.  
CW, 0dB CF  
0
–1  
–25  
–20  
–15  
–10  
–5  
0
5
10  
15  
INPUT (dBm)  
Figure 11. Reported Crest Factor of Various Waveforms  
Rev. 0| Page 5 of 7  
CN-0187  
Circuit Note  
The data in this circuit note were generated using a Rohde &  
Schwarz SMT-03 RF signal source and an Agilent E3631A  
power supply. The signal source was set to the frequencies  
indicated in the graphs, and the input power was stepped and  
data recorded in 1 dB increments.  
Equipment Needed  
PC with a USB port and Windows® XP or Windows Vista®  
(32-bit), or Windows® 7 (32-bit)  
EVAL-CN0187-SDPZ circuit evaluation board  
EVAL-SDP-CB1Z SDP evaluation board  
CN0187 evaluation software  
Information and details regarding how to use the evaluation  
software for data capture can be found in the CN0187  
Evaluation Software Readme file.  
Power supply: +6 V, or +6 V “wall wart”  
RF signal source  
Information regarding the SDP board can be found in the  
SDP User Guide.  
Coaxial RF cable with SMA connectors  
LEARN MORE  
Getting Started  
CN0187 Design Support Package:  
Load the evaluation software by placing the CN0187 Evaluation  
Software disc in the CD drive of the PC. Using "My Computer,"  
locate the drive that contains the evaluation software disc and  
open the Readme file. Follow the instructions contained in the  
Readme file for installing and using the evaluation software.  
http://www.analog.com/CN0187-DesignSupport  
SDP User Guide  
Ardizzoni, John. A Practical Guide to High-Speed Printed-Circuit-  
Board Layout, Analog Dialogue 39-09, September 2005.  
CN-0150 Circuit Note, Software-Calibrated, 1 MHz to 8 GHz,  
70 dB RF Power Measurement System Using the AD8318  
Logarithmic Detector, Analog Devices.  
Functional Block Diagram  
See Figure 1 of this circuit note for the circuit block diagram,  
and the “EVAL-CN0187-SDPZ-SCH” pdf file for the circuit  
schematics. This file is contained in the CN0187 Design  
Support Package.  
MT-031 Tutorial, Grounding Data Converters and Solving the  
Mystery of AGND” and “DGND”, Analog Devices.  
MT-073 Tutorial, High Speed Variable Gain Amplifiers (VGAs),  
Setup  
Analog Devices.  
Connect the 120-pin connector on the EVAL-CN0187-SDPZ  
circuit board to the connector marked “CON Aon the  
EVAL-SDP-CB1Z evaluation (SDP) board. Nylon hardware  
should be used to firmly secure the two boards, using the holes  
provided at the ends of the 120-pin connectors. Using an  
appropriate RF cable, connect the RF signal source to the  
EVAL-CN0187-SDPZ board via the SMA RF input connector.  
With power to the supply off, connect a +6 V power supply to  
the pins marked “+6 V” and “GND” on the board. If available, a  
+6 V "wall wart" can be connected to the barrel jack connector  
on the board and used in place of the +6 V power supply.  
Connect the USB cable supplied with the SDP board to the USB  
port on the PC. Note: Do not connect the USB cable to the mini  
USB connector on the SDP board at this time.  
MT-077 Tutorial, Log Amp Basics, Analog Devices.  
MT-078 Tutorial, High Speed Log Amps, Analog Devices.  
MT-081 Tutorial, RMS-to-DC Converters, Analog Devices.  
MT-101 Tutorial, Decoupling Techniques, Analog Devices.  
Whitlow, Dana. Design and Operation of Automatic Gain  
Control Loops for Receivers in Modern Communications  
Systems. Chapter 8. Analog Devices Wireless Seminar. 2006.  
Data Sheets and Evaluation Boards  
CN-0187 Circuit Evaluation Board (EVAL-CN0187-SDPZ)  
System Demonstration Platform (EVAL-SDP-CB1Z)  
ADL5502 Data Sheet  
Test  
ADL5502 Evaluation Board  
Apply power to the +6 V supply (or “wall wart”) connected to  
EVAL-CN0187-SDPZ circuit board. Launch the evaluation  
software and connect the USB cable from the PC to the USB  
mini-connector on the SDP board. The software will be able to  
communicate to the SDP board if the Analog Devices System  
Development Platform driver is listed in the Device Manager.  
AD7266 Data Sheet  
AD7266 Evaluation Board  
ADA4891 Data Sheet  
Once USB communications are established, the SDP board can  
now be used to send, receive, and capture serial data from the  
EVAL-CN0187-SDPZ board.  
Rev. 0| Page 6 of 7  
Circuit Note  
CN-0187  
REVISION HISTORY  
4/11—Revision 0: Initial Version  
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©2011 Analog Devices, Inc. All rights reserved. Trademarks and  
registered trademarks are the property of their respective owners.  
CN09569-0-4/11(0)  
Rev. 0| Page 7 of 7  

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ADI

CN-0221

USB-Based Temperature Monitor Using the ADuCM360 Precision Analog Microcontroller
ADI

CN-0227

High Performance, 16-Bit, 250 MSPS Wideband Receiver with Antialiasing Filter
ADI

CN-0232

Minimizing Spurious Outputs Using a Synthesizer with an Integrated VCO and an External PLL Circuit
ADI

CN-0243

High Dynamic Range RF Transmitter Signal Chain Using Single External Frequency Reference for DAC Sample Clock and IQ Modulator LO Generation
ADI

CN-0245

Wideband LO PLL Synthesizer with Simple Interface to Quadrature Demodulators
ADI

CN-0248

An IQ Demodulator-Based IF-to-Baseband Receiver with IF and Baseband Variable Gain and Programmable Baseband Filtering
ADI

CN-0255

Low Power, Low Noise and Distortion ail-to-Rail Output Amplifiers
ADI

CN-0259

High Performance 65 MHz Bandwidth Quad IF Receiver with Antialiasing Filter and 184.32 MSPS Sampling Rate
ADI

CN-0267

Complete 4 mA to 20 mA Loop Powered Field Instrument with HART Interface
ADI