Agilent 423B, 8470B, 8472B, 8473B/C Low Barrier Schottky Diode Detectors Data Sheet • • • • • Agilent 423B Excellent broadband flatness Low broadband SWR High burnout protection Environmentally rugged Field replaceable diode elements I 50 µA/div Typical LBSD Typical Schottky Diode V 50 mV/div Agilent 8470B Figure 1. Diode V/I characteristics Agilent 8472B Agilent 8473B Agilent 8473C Agilent offers a complete family of high performance Low Barrier Schottky Diode Detectors which cover the 10 MHz to 26.5 GHz frequency range. These general purpose components are widely used for CW and pulsed power detection, leveling of sweepers, and frequencyresponse testing of other microwave components. These detectors do not require a dc bias and can be used with common oscilloscopes, thus their simplicity of operation and excellent broadband performance make them useful measurement accessories. These detectors use a Low-Barrier Schottky Diode (LBSD), specially fabricated with low origin resistance and low junction capacitance. This results in improved broadband flatness and SWR over point-contact diode detectors, thus yielding more accurate measurements. These detectors also offer very good ruggedness and burnout protection. As with all Agilent detectors, these models integrate the diode with the other circuit elements thus minimizing stray reactances and optimizing broadband performance. For economical field repair, replaceable detector modules are available. Field-replaceable detector elements In the event of diode burnout, field-replaceable detector elements are available for economical customer repair. The critical components are supplied (and tested) as an integrated unit, with the mount playing only a minor role in determining frequency response and SWR. The following table lists field-replaceable detector modules that have been tested to their respective specifications. +1.00 Frequency response (dB) +0.75 +0.50 LBSD specifications +0.25 Typical LBSD detector 0 Table 1. -0.25 -0.50 -0.75 -1.00 0.01 2 4 6 8 10 12 14 16 18 Frequency (GHz) Figure 2. Detector frequency response specifications 1.8 Agilent Model Agilent replacement part number 423B 00423-60003 8470B 08470-60012 8472B 08470-60012 8473B 08473-80001 Option 8473B–001 08473-80002 Option 8473B–003 08473-80003 8473C 08473-80004 Option 8473C–001 08473-80005 Option 8473C–003 08473-80006 Frequency response (dB) 1.7 423B 1.6 1.5 D L LBSD specifications 1.4 1.3 8470B 1.2 Typical LBSD detector D L 1.1 1.0 0.01 RF connector 2 4 6 8 10 12 14 16 8472B 8473B/C 18 Frequency (GHz) D L Figure 3. Detector SWR specifications Figure 5. Drawing dimensions given in specification table 1.0 500.0 50.0 Typical SWR for LBSD detector models 0.6 2.0 Source SWR Output voltage (mV) Maximum mismatch error (±dB) 0.8 1.5 Source SWR 0.4 0.2 LBSD 0.5 Square law loaded Without load 0.05 0 LBSD 5.0 0.005 1.0 1.2 1.4 1.6 1.8 2.0 -50 Detector SWR -40 -30 -20 Input power (dBm) Figure 4. Measurement uncertainty due to detector source mismatch Figure 6. Typical detector square-law response 2 -10 0 Specifications Specifications1 Agilent 423B Agilent 8473B Agilent 8473C Agilent 8470B Agilent 8472B Frequency range 0.01 to 12.4 GHz 0.01 to 18 GHz 0.01 to 26.5 GHz 0.01 to 18 GHz 0.00 to 18 GHz Frequency response Octave band flatness (over any octave 0 01 to 8 GHz) ±0.2 dB ±0.2 dB ±0.2 dB ±0.2 dB ±0.2 dB Broadband flatness 0.01 dB to 12.4 GHz: ±0.3 dB 0.01 to 12.4 GHz: ±0.3 dB 0.01 to 18 GHZ: ±0.6 dB 0.01 to 12.4 GHz: ±0.3 dB 0.01 to 20 GHz: ±6 dB 20 to 26.5 GHz: ±1.5 dB from a 3.3 dB linear slope 0.01 to 12.4 GHz: ±0.3 dB 0.01 to 15 GHz: ±0.5 dB 0.01 to 18 GHz: ±0.6 dB 0.01 to 12.4 GHz: ±0.3 dB 0.01 to 15 GHz: ±0.5 dB SWR3, maximum (50Ω characteristic impedance) 0.01 to 4 GHz: 1.15 4 to 12.4 G Hz: 1.30 0.01 to 4 GHz: 1.2 4 to 18 GHz: 1.5 0.01 to 4 GHz: 1.2 4 to 18 GHz: 1.5 18 to 26.5 GHz: 2.2 0.01 to 4 GHz: 1.15 4 to 15 GHz: 1.30 15 to 18 GHz: 1.70 0.01 to 4.5 GHz: 1.20 4.5 to 7 GHz: 1.35 Maximum operating input (Peak or average) 200 mW 200 mW 200 mW 200 mW 200 mW Short- term maximum Input (less than 1 min.) 1 watt (typical) 1 watt (typical) 1 watt (typical) 1 watt (typical) 1 watt (typical) Sensitivity4 > 0.5 mV/μW > 0.5 mV/μW 0.01 to 18 GHz: > 0.5 mV/μW 18 to 26.5 GHz: > 0.1 8 mV/μW > 0.5 mV/μW > 0.5 mV/μW Noise (μV peak-to-peak with CW power applied to produce 100 mV output) < 50 μV < 50 μV < 50 μV < 50 μV < 50 μV Environmental qualifications Operating temperature Vibration Shock 0 to 55 °C 20 G’s, 80 - 2000 Hz 100 G’s, 11 ms -20 °C to +85 °C 20 G’s, 80 - 2000 Hz 100 G’s, 11 ms -20 °C to +85 °C 20 G’s, 80 - 2000 Hz 100 G’s, 11 ms -20 °C to +85 °C 20 G’s, 80 - 2000 Hz 100 G’s, 11 ms -20 °C to +85 °C 20 G’s, 80 - 2000 Hz 100 G’s, 11 ms Output polarity Negative Negative Negative Negative Negative Input connector Type N Male 3.5 mm Male (SMA Compatible) 3.5 mm Male (SMA Compatible) APC-7 SMA Male 2 Output connector BNC Female BNC Female BNC Female BNC Female BNC Female Video impedance 1 kΩ to 2 kΩ 1.3 kΩ (typical) 1 kΩ to 2 kΩ 1.3 kΩ (typical) 1 kΩ to 2 kΩ 1.3 kΩ (typical) 1 kΩ to 2 kΩ 1.3 kΩ (typical) 1 kΩ to 2 kΩ 1.3 kΩ (typical) RF bypass capacitor 20 pF to 60 pF 30 pF (typical) 20 pF to 60 pF 30 pF (typical) 20 pF to 60 pF 30 pF (typical) 20 pF to 60 pF 30 pF (typical) 20 pF to 60 pF 30 pF (typical) Dimensions in mm (inches) Length Diameter 63 (2.47) 20 (038) 48 (1.89) 10 (0.39) 43 (1.89) 10 (0.39) 64 (2.50) 19 (0.75) 64 (2.50) 14 (0.56) Weight in grams (oz) Net Shipping 114 (4) 454 (16) 14 (0.5) 454 (16) 14 (0.5) 454 (16) 114 (4) 454 (16) 57 (2) 454 (16) Tracking: 0.01 to 12.4 GHz: ±0.2 dB Tracking: 0.01 to 12.4 GHz: ±0.2 dB 12.4 to 18 GHz: ±0.3 dB Tracking: 0.01 to 12.4 GHz: ±0.2 dB 12.4 to 18 GHz: ±0.3 dB 18 to 26.5 GHz: ±0.5 dB Tracking: 0.01 to 12.4 GHz: ±0.2 dB 12.4to 18 GHz: ±0.3 dB Tracking: 0.01 to 12.4 GHz: ±0.2 dB 12.4to 18 GHz: ±0.3 dB xxxx-002 Optimum square-law load Optimum square -law load Optimum square -law load Optimum square -law load Optimum square -law load Optimum square -law load xxxx-003 Positive polarity out Positive polarity Output Positive polarity Output Positive polarity Output Positive polarity Output Positive polarity Output Options xxxx-001 Matched response Provides a pair of detectors with matched frequency response 1. Specifications given for +25 °C unless otherwise noted. Specifications describe the instrument’s warranted performance. Supplemental characteristics (in italics) are intended to provide information useful in applying the instrument by giving typical, but not warranted, performance parameters. 2. RF may leak through video connector especially below 1 GHz; if objectionable, this may be eliminated with low-pass filter. 3. SWR measured at 2 dBm. 4. Sensitivity decreases with increasing temperature typically 0.5 dB from 20 °C to +25 °C, 0.5 dB from +25 °C to +40v C. 1 dB from +40 °C to +55 °C, 1.25 dB from +55 °C to +75 °C, 1 dB from +75 °C to +85 °C. 3 Applications www.agilent.com These detectors can be used in a wide variety of applications ranging from lab and production measurements to systems components. Because of their flatness and match, these detectors can be used for accurately measuring transmission and reflection characteristics in CW or swept-frequency measurements. For these applications in which both flat-frequency response and square-law characteristics are important, Option 423B, 847xB/C–001 provides a matched pair of detectors that track each other within a few tenths of a dB, and Option 423B, 847xB/C–002 (external square-law load) extends the square-law region up to at least 0.1 mW (10 dBm). Other common applications include use with a coupler or power splitter to externally level a source, and to display pulsed-RF and AM-modulated signals. For more information on Agilent Technologies’ products, applications or services, please contact your local Agilent office. The complete list is available at: For OEM and systems applications, the broadband flatness and ruggedness of these detectors make them particularly well suited for use in closed-loop leveling circuits in microwave instrumentation. Square-law response For many reflection and transmission measurements it is desirable to use the detector in its square-law region where its output voltage is proportional to the input RF power. As shown in figure 5, the LBSD typically operate within 0.5 dB of square-law from the tangential signal sensitivity (TSS) level up to 18 dBm. By specifying Option 423B, 847xB/C–002, a specially selected loading resistor is provided which extends this square-law region to approximately 8 dBm with an associated decrease in sensitivity as shown in figure 5. Pulse response The LBSD detectors have extremely good pulse detection characteristics when working into low-capacitance, low-resistance loads. When loaded externally with 50 Ω the LBSD detector can typically display 8 to 12 ns rise times. Figure 6 illustrates the equivalent circuit for the detector, as well as typical values for the diode impedance and the RF bypass capacitor. Diode impedance RF in 50 V RF bypass capacitor Video out www.agilent.com/find/contactus Americas Canada Latin America United States (877) 894-4414 305 269 7500 (800) 829-4444 Asia Pacific Australia China Hong Kong India Japan Korea Malaysia Singapore Taiwan Thailand 1 800 629 485 800 810 0189 800 938 693 1 800 112 929 0120 (421) 345 080 769 0800 1 800 888 848 1 800 375 8100 0800 047 866 1 800 226 008 Europe & Middle East Austria 01 36027 71571 Belgium 32 (0) 2 404 93 40 Denmark 45 70 13 15 15 Finland 358 (0) 10 855 2100 France 0825 010 700* *0.125 €/minute Germany 07031 464 6333 Ireland 1890 924 204 Israel 972-3-9288-504/544 Italy 39 02 92 60 8484 Netherlands 31 (0) 20 547 2111 Spain 34 (91) 631 3300 Sweden 0200-88 22 55 Switzerland 0800 80 53 53 United Kingdom 44 (0) 118 9276201 Other European Countries: www.agilent.com/find/contactus Revised: October 6, 2008 Figure 7. Detector equivalent circuit Ordering Information To add options to a product, use the following ordering scheme: Model: 847xB/C (x= 0, 2 or 3) Example options: 8472B–001, 8473C–001 423B–001 847xB/C–001 Matched pair of detectors 423B–002 847xB/C–002 External square-law load www.agilent.com/find/emailupdates Get the latest information on the products and applications you select. Product specifications and descriptions in this document subject to change without notice. © Agilent Technologies, Inc. 2009 Printed in USA, May 25, 2009 5952-8299