AD831

AD831 (Rev. D)

Document overview

• Manufacturer or author: Analog Devices, Inc.
• PDF pages: 16

Technical content

FEATURES

+24 dBm Third Order Intercept (IP3) +10 dBm 1 dB Compression Point Low LO Drive Required: –10 dBm Bandwidth

500 MHz RF and LO Input Bandwidths

250 MHz Differential Current IF Output

DC to >200 MHz Single-Ended Voltage IF Output Single- or Dual-Supply Operation DC Coupled Using Dual Supplies All Ports May Be DC Coupled No Lower Frequency Limit—Operation to DC User-Programmable Power Consumption

APPLICATIONS

High Performance RF/IF Mixer Direct to Baseband Conversion Image-Reject Mixers I/Q Modulators and Demodulators PRODUCT DESCRIPTION The AD831 is a low distortion, wide dynamic range, monolithic mixer for use in such applications as RF to IF downconversion in HF and VHF receivers, the second mixer in DMR base sta- tions, direct-to-baseband conversion, quadrature modulation and demodulation, and doppler shift detection in ultrasound imaging applications. The mixer includes an LO driver and a low noise output amplifier and provides both user-programmable power consumption and third order intercept point. The AD831 provides a +24 dBm third order intercept point for –10 dBm LO power, thus improving system performance and reducing system cost compared to passive mixers, by eliminating the need for a high pow er LO driver and its attendant shielding and isolation problems. The RF, IF, and LO ports may be dc or ac coupled when the mixer is operating from ±5 V supplies or ac coupled when oper- ating from a single-supply of 9 V minimum. The mixer operates with RF and LO inputs as high as 500 MHz. The mixer’s IF output is available as either a differential current output or a single-ended voltage output. The differential output is from a pair of open collectors and may be ac coupled via a trans- former or capacitor to provide a 250 MHz output bandwidth. In downconversion applications, a single capacitor connected across these outputs implements a low-pass filter to reduce harmonics directly at the mixer core, simplifying output filtering. When building a quadrature-amplitude modulator or image reject mixer, the differential current outputs of two AD831s may be summed by connecting them together. An integral low noise amplifier provides a single-ended voltage output and can drive such low impedance loads as filters, 50  amplifier inputs, and A/D converters. Its small signal bandwidth exceeds 200 MHz. A single resistor connected between pins OUT and FB sets its gain. The amplifier’s low dc offset allows its use in such direct-coupled applications as direct-to-baseband conversion and quadrature-amplitude demodulation. The mixer’s SSB noise figure is 10.3 dB at 70 MHz using its output amplifier and optimum source impedance. Unlike passive mixers, the AD831 has no insertion loss and does not require an external diplexer or passive termination. A programmable-bias feature allows the user to reduce power consumption, with a reduction in the 1 dB compression point and third-order intercept. This permits a tradeoff between dynamic range and power consumption. For example, the AD831 may be used as a second mixer in cellular and two-way radio base stations at reduced power while still providing a substantial performance improvement over passive solutions. PRODUCT HIGHLIGHTS 1. –10 dBm LO Drive for a +24 dBm Output Referred Third Order Intercept Point 2. Single-Ended Voltage Output 3. High Port-to-Port Isolation 4. No Inser tion Loss 5. Single- or Dual-Supply Operation 6. 10.3 dB Noise Figure Rev. D Document Feedback 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. Tel: 781.329.4700 ©2018 Analog Devices, Inc. All rights reserved. Technical Support www.analog.com

–2– AD831–SPECIFICATIONS AD831 –3– Parameter Conditions Min T yp Max Unit RF INPUT Bandwidth –10 dBm Signal Level, IP3 ≥ +20 dBm 400 MHz

10.7 MHz IF and High Side Injection

1 dB Compression Point 10 dBm Common-Mode Range ±1 V Bias Current DC Coupled 160 500 µA DC Input Resistance Differential or Common Mode 1.3 k Capacitance 2 pF IF OUTPUT Bandwidth Single-Ended V oltage Output, –3 dB Level = 0 dBm, RL = 100  200 MHz Conv ersion Gain Terminals OUT and VFB Connected 0 dB Output Offset V oltage DC Measurement; LO Input Switched ±1 –40 +15 +40 mV Slew Rate 300 V/µs Output V oltage Swing RL = 100 , Unity Gain ±1.4 V Short Circuit Cur rent 75 mA LO INPUT Bandwidth –10 dBm Input Signal Level 400 MHz Maximum Input Level –1 +1 V Common-Mode Range –1 +1 V Minimum Switching Level Differential Input Signal 200 mV p-p Bias Current DC Coupled 17 50 µA Resistance Differential or Common Mode 500  Capacitance 2 pF ISOLATION BETWEEN POR TS LO-to-RF LO = 100 MHz, RS = 50 , 10.7 MHz IF 70 dB LO-to-IF LO = 100 MHz, RS = 50 , 10.7 MHz IF 30 dB RF-to-IF RF = 100 MHz, RS = 50 , 10.7 MHz IF 45 dB DISTOR TION AND NOISE LO = –10 dBm, f = 100 MHz, IF = 10.7 MHz Third Order Intercept Output Referred, ±100 mV LO Input 24 dBm Second Order Intercept Output Referred, ±100 mV LO Input 62 dBm 1 dB Compression Point RL = 100 , RBIAS =  10 dBm Noise Figure, SSB Ma tched Input, RF = 70 MHz, IF = 10.7 MHz 10.3 dB Matched Input, RF = 150 MHz, IF = 10.7 MHz 14 dB POWER SUPPLIES Recommended Supply Range Dual Supply ±4.5 ±5.5 V Single Supply 9 11 V Quiescent Current * For Best Third Order Intercept Point Performance 100 125 mA BIAS Pin Open Circuited *Quiescent current is programmable. Specifications subject to change without notice. (TA = +25C and VS = 5 V unless otherwise noted; all values in dBm assume 50  load.) REV. C REV. D

–2– AD831–SPECIFICATIONS AD831 –3– PIN DESCRIPTION Pin No. Mnemonic Description

1 VP Positive Supply Input

2 IFN Mixer Current Output

3 AN Amplifier Negative Input

4 GND Ground

5 VN Negative Supply Input

6 RFP RF Input

7 RFN RF Input

8 VN Negative Supply Input

9 VP Positive Supply Input

10 LON Local Oscillator Input

11 LOP Local Oscillator Input

12 VP Positive Supply Input

13 GND Ground

14 BIAS Bias Input

15 VN Negative Supply Input

16 OUT Amplifier Output

17 VFB Amplifier Feedback Input

18 COM Amplifier Output Common

19 AP Amplifier Positive Input

20 IFP Mixer Current Output

Operating Temperature Range PIN CONFIGURATION 20-Lead PLCC CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD831 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. NOTES

1 Stresses above those listed under Absolute Maximum Ratings may cause permanent

damage to the device. This is a stress rating only and 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.

2 Thermal Characteristics:

20-Lead PLCC Package: JA = 110°C/W; JC = 20°C/W . Note that the JA = 110°C/W value is for the package measured while suspended in still air; mounted on a PC board, the typical value is JA = 90°C/W due to the conduction provided by the AD831’s package being in contact with the board, which serves as a heat sink. REV. C REV. D

–4– AD831–Typical Performance Characteristics AD831 –5– 10 1000100 FREQUENCY (MHz) SECOND ORDER INTERCEPT (dBm) TPC 4. Second Order Intercept vs. Frequency 10 1000100 FREQUENCY (MHz) ISOLATION (dB) TPC 5. LO-to-RF Isolation vs. Frequency 10 1000100 3 x RF – IF 2 x RF – IF RF – IF 3 x RF – IF 2 x RF – IF RF – IF FREQUENCY (MHz) FREQUENCY (dB) TPC 6. RF-to-IF Isolation vs. Frequency TPC 1. Third Order Intercept vs. Frequency, IF Held Constant at 10.7 MHz 10 1000100 FREQUENCY (MHz) ISOLATION (dB) TPC 2. IF-to-RF Isolation vs. Frequency 10 1000100 LO FREQUENCY (MHz) ISOLATION (dB) 3 x LO – IF 2 x LO – IF TPC 3. LO-to-IF Isolation vs. Frequency REV. C REV. D

–4– AD831–Typical Performance Characteristics AD831 –5– 10 1000100 FREQUENCY (MHz) 1dB COMPRESSION POINT (dBm) TPC 7 . 1 dB Compression Point vs. Frequency, Gain = 1 10 1000100 FREQUENCY (MHz) 1dB COMPRESSION POINT (dBm) TPC 8. 1 dB Compression Point vs. RF Input, Gain = 2 TPC 9. Third Order Intercept vs. Frequency, LO Held Constant at 241 MHz 1.00 0.50 –1.00 0.00 –0.25 –0.75 0.75 0.25 –0.50 10 1000100 FREQUENCY (MHz) THIRD ORDER INTERCEPT (dBm) TPC 10. Gain Error vs. Frequency, Gain = 1 10 1000100 FREQUENCY (MHz) THIRD ORDER INTERCEPT (dBm) TPC 1 1. 1 dB Compression Point vs. Frequency, Gain = 4 0 600100 200 300 400 500 LO LEVEL = –10dBm IF = 10.7MHz VS = 8V VS = 9V FREQUENCY (MHz) THIRD ORDER INTERCEPT (dBm) TPC 12. Input 1 dB Compression Point vs. Frequency, Gain = 1, 9 V Single Supply REV. C REV. D

–6– AD831 –7– TPC 13. Input Third Order Intercept, 9 V Single Supply TPC 14. Input Second Order Intercept, 9 V Single Supply 1200 1000 50 250100 150 200 800 600 400 200 4.0 3.5 3.0 2.5 2.0 INPUT CAPACITANCE INPUT RESISTANCE INPUT CAPACITANCE FREQUENCY (MHz) INPUT RESISTANCE () TPC 15. Input Impedance vs. Frequency, ZIN = R C FREQUENCY (MHz) NOISE FIGURE (dB) 50 250100 150 200 TPC 16. Noise Figure vs. Frequency, Matched Input REV. C REV. D

noise output amplifier, and a bias circuit (Figure 1). is driven fully positive or negative. Figure 1. Simplified Schematic Diagram

70 MHz IF, a –3 dB frequency of 140 MHz might be chosen,

Figure 4. Low-Pass Filtering Using External Capacitors collector outputs of the mixer’s core and OUT connects to VFB. Figure 5. Output Amplifier Connected for Unity (1:1 turns ratio) to pins IFN and IFP as shown in Figure 2. Figure 2. Connections for Transformer Coupling to Figure 3. Programming the Quiescent Current

–12– AD831 –13– Connections Quadrature Demodulation Two AD831 mixers may have their RF inputs connected in parallel and have their LO inputs driven in phase quadrature (Figure 11) to provide demodulated in-phase (I) and quadrature (Q) outputs. The mixers’ inputs may be connected in parallel and a single termination resistor used if the mixers are located in close prox- imity on the PC board. Figure 1 1. Connections for Quadrature Demodulation REV. C REV. D

–12– AD831 –13– Table I. AD831 Mixer Table, 4.5 V Supplies, LO = –9 dBm LO Level –9.0 dBm, LO Frequency 130.7 MHz, Data File imdTB10771 RF Level 0.0 dBm, RF Frequency 120 MHz Temperature Ambient Dut Supply ±4.50 V VPOS Current 90 mA VNEG Current 91 mA Intermodulation table RF harmonics (rows)  LO harmonics (columns). First row absolute value of nRF – mLO, and second row is the sum. 1 2 3 4 5 6 7 –31.6 Table II. AD831 Mixer Table, 5 V Supplies, LO = –9 dBm LO Level –9.0 dBm, LO Frequency 130.7 MHz, Data File imdTB13882 RF Level 0.0 dBm, RF Frequency 120 MHz Temperature Ambient Dut Supply ±5.00 V VPOS Current 102 mA VNEG Current 102 mA Intermodulation table RF harmonics (rows)  LO harmonics (columns). First row absolute value of nRF – mLO, and second row is the sum. 0 1 2 3 4 5 6 7 REV. C REV. D

–14– AD831 –15– Table III. AD831 Mixer Table, 3.5 V Supplies, LO = –20 dBm LO Level –20.0 dBm, LO Frequency 130.7 MHz, Data File G1T1K 0771 RF Level 0.0 dBm, RF Frequency 120 MHz Temperature Ambient Dut Supply ±3.50 V VPOS Current 55 mA VNEG Current 57 mA Intermodulation table RF harmonics (rows)  LO harmonics (columns). First row absolute value of nRF – mLO, and second row is the sum. 1 2 3 4 5 6 7 1 –30.3 Table IV . AD831 Mixer Table, 5 V Supplies, 1 k Bias Resistor, LO = –20 dBm LO Level –20.0 dBm, LO Frequency 130.7 MHz, Data File G1T1K 3881 RF Level 0.0 dBm, RF Frequency 120 MHz Temperature Ambient Dut Supply ±3.50 V VPOS Current 59 mA VNEG Current 61 mA Intermodulation table RF harmonics (rows)  LO harmonics (columns). First row absolute value of nRF – mLO, and second row is the sum. 0 1 2 3 4 5 6 7 REV. C REV. D

Rev. D | Page 16 of 16 OUTLINE DIMENSIONS COMPLIANT TO JEDEC STANDARDS MO-047-AA CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. 0.020 (0.50) R BOTTOM VIEW (PINS UP) 0.021 (0.53) 0.013 (0.33) 0.330 (8.38) 0.290 (7.37) 0.032 (0.81) 0.026 (0.66) 0.056 (1.42) 0.042 (1.07) 0.20 (0.51) MIN 0.120 (3.04) 0.090 (2.29) TOP VIEW (PINS DOWN) 0.395 (10.03) 0.385 (9.78)SQ 0.356 (9.04) 0.350 (8.89) SQ 0.048 (1.22 ) 0.042 (1.07) 0.048 (1.22) 0.042 (1.07) 0.020 (0.51) R 0.050 (1.27) BSC 0.180 (4.57) 0.165 (4.19) 0.045 (1.14) 0.025 (0.64) R PIN 1 IDENTIFIER Figure 14. 20-Lead Plastic Leaded Chip Carrier [PLCC]

REVISION HISTORY

10/2018—Rev. C to Rev. D 6/2003—Rev. B to Rev. C ©2018 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the prop erty of their respective owners. D00882-0-10/18(D)