LT5560 0.01MHz to 4GHz Low Power Active Mixer U DESCRIPTIO FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ The LT®5560 is a low power, high performance broadband active mixer. This double-balanced mixer can be driven by a single-ended LO source and requires only –2dBm of LO power. The balanced design results in low LO leakage to the output, while the integrated input amplifier provides excellent LO to IN isolation. The signal ports can be impedance matched to a broad range of frequencies, which allows the LT5560 to be used as an up- or down-conversion mixer in a wide variety of applications. Up or Downconverting Applications Noise Figure: 9.3dB Typical at 900MHz Output Conversion Gain: 2.4dB Typical IIP3: 9dBm Typical at ICC = 10mA Adjustable Supply Current: 4mA to 13.4mA Low LO Drive Level: –2dBm Single-Ended or Differential LO High Port-to-Port Isolation Enable Control with Low Off-State Leakage Current Single 2.7V to 5V Supply Small 3mm × 3mm DFN Package The LT5560 is characterized with a supply current of 10mA; however, the DC current is adjustable, which allows the performance to be optimized for each application with a single resistor. For example, when biased at its maximum supply current (13.4mA), the typical upconverting mixer IIP3 is +10.8dBm for a 900MHz output. U APPLICATIO S ■ ■ ■ ■ ■ ■ ■ Portable Wireless CATV/DBS Receivers WiMAX Radios PHS Basestations RF Instrumentation Microwave Data Links VHF/UHF 2-Way Radios , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. U TYPICAL APPLICATIO Low Cost 900MHz Downconverting Mixer 2.7V TO 5.3V LOIN 1µF 760MHz IFOUT and IM3 Levels vs RF Input Power 10 0 100pF 15nH 1 4.7pF EN 2 3 RFIN 900MHz 100pF 6.8nH LO+ EN VCC IN+ U1 LT5560 8 7 6.8nH IN– PGND 9 270nH 4.7pF OUT+ 6 OUT – 5 4.7pF 4 15nH LO– 270nH IFOUT 33pF 140MHz POWER LEVEL (dBm/Tone) 1nF 100pF IFOUT –10 –20 –30 –40 –50 –60 –70 IM3 TA = 25°C VCC = 3V ICC = 13.3mA fLO = 760MHz fIF = 140MHz –80 –20 –18 –16 –14 –12 –10 –8 –6 –4 –2 RF INPUT POWER (dBm) 270nH 4.7pF 0 5560 TA02 5560 TA01 5560f 1 LT5560 U W U PACKAGE/ORDER I FOR ATIO U W W W ABSOLUTE AXI U RATI GS (Note 1) TOP VIEW Supply Voltage .........................................................5.5V Enable Voltage ................................ –0.3V to VCC + 0.3V LO Input Power (Differential) .............................+10dBm Input Signal Power (Differential) ........................+10dBm IN+, IN – DC Currents ..............................................10mA OUT+, OUT – DC Current .........................................10mA TJMAX .................................................................... 125°C Operating Temperature Range .................–40°C to 85°C Storage Temperature Range...................–65°C to 125°C LO– 1 EN 2 IN+ 3 IN– 9 4 8 LO+ 7 VCC 6 OUT+ 5 OUT – DD PACKAGE 8-LEAD (3mm × 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 43°C/W EXPOSED PAD (PIN 9) IS GND MUST BE SOLDERED TO PCB ORDER PART NUMBER DD PART MARKING LT5560EDD LCBX Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/ Consult LTC Marketing for parts specified with wider operating temperature ranges. DC ELECTRICAL CHARACTERISTICS VCC = 3V, EN = 3V, TA = 25°C, unless otherwise noted. Test circuit shown in Figure 1. (Note 3) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.7 3 5.3 V Power Supply Requirements (VCC) Supply Voltage Supply Current VCC = 3V, R1 = 3Ω 10 12 mA Shutdown Current EN = 0.3V, VCC = 3V 0.1 10 µA Enable (EN) Low = Off, High = On EN Input High Voltage (On) 2 V EN Input Low Voltage (Off) Enable Pin Input Current 0.3 EN = 3V EN = 0.3V V 25 0.1 µA µA Turn On Time 2 µs Turn Off Time 5 µs AC ELECTRICAL CHARACTERISTICS (Notes 2 and 3) PARAMETER CONDITIONS MIN TYP MAX UNITS Signal Input Frequency Range (Note 4) Requires External Matching < 4000 MHz LO Input Frequency Range (Note 4) Requires External Matching < 4000 MHz Signal Output Frequency Range (Note 4) Requires External Matching < 4000 MHz 5560f 2 LT5560 AC ELECTRICAL CHARACTERISTICS VCC = 3V, EN = 3V, TA = 25°C, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), PLO = –2dBm, unless otherwise noted. Test circuits are shown in Figures 1, 2 and 3. (Notes 2 and 3) PARAMETER CONDITIONS MIN Signal Input Return Loss Z = 50Ω, External Match 15 dB LO Input Return Loss Z = 50Ω, External Match 15 dB Signal Output Return Loss Z = 50Ω, External Match 15 dB LO Input Power TYP MAX –6 to 1 UNITS dBm Upconverting Mixer Configuration: VCC = 3V, EN = 3V, TA = 25°C, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), PLO = –2dBm, unless otherwise noted. High side LO for 450MHz tests, low side LO for 900MHz and 1900MHz tests. Test circuits are shown in Figures 1 and 3. (Notes 2, 3 and 5) PARAMETER CONDITIONS Conversion Gain fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz Conversion Gain vs Temperature TA = –40°C to 85°C, fOUT = 900MHz Input 3rd Order Intercept MIN TYP MAX UNITS 2.7 2.4 1.2 dB dB dB – 0.015 dB/°C fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz 9.6 9.0 8.0 dBm dBm dBm Input 2nd Order Intercept fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz 46 47 30 dBm dBm dBm Single Sideband Noise Figure fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz 8.8 9.3 10.3 dB dB dB IN to LO Isolation (with LO Applied) fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz 69 64 64 dB dB dB LO to IN Leakage fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz –63 –54 –36 dBm dBm dBm LO to OUT Leakage fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz –44 –41 –36 dBm dBm dBm Input 1dB Compression Point fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz 0.4 –2.8 –0.8 dBm dBm dBm Downconverting Mixer Configuration: VCC = 3V, EN = 3V, TA = 25°C, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), PLO = –2dBm, unless otherwise noted. High side LO for 450MHz tests, low side LO for 900MHz and 1900MHz tests. Test circuits are shown in Figures 2 and 3. (Notes 2, 3 and 5) PARAMETER CONDITIONS Conversion Gain fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz Conversion Gain vs Temperature TA = – 40°C to 85°C, fIN = 900MHz Input 3rd Order Intercept Single Sideband Noise Figure MIN TYP 2.7 2.6 2.3 MAX UNITS dB dB dB – 0.015 dB/°C fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz 10.1 9.7 5.6 dBm dBm dBm fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz 10.5 10.1 10.8 dB dB dB 5560f 3 LT5560 AC ELECTRICAL CHARACTERISTICS Downconverting Mixer Configuration: VCC = 3V, EN = 3V, TA = 25°C, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), PLO = –2dBm, unless otherwise noted. High side LO for 450MHz tests, low side LO for 900MHz and 1900MHz tests. Test circuits are shown in Figures 2 and 3. (Notes 2, 3 and 5) PARAMETER CONDITIONS MIN IN to LO Isolation (with LO Applied) fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz 52 52 25 dB dB dB LO to IN Leakage fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz –52 –57 –37 dBm dBm dBm LO to OUT Leakage fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz –47 –63 –24 dBm dBm dBm 2RF – 2LO Output Spurious (Half IF) Product (fIN = fLO + fOUT/2) 450MHz: fIN = 485MHz, fOUT = 70MHz 900MHz: fIN = 830MHz, fOUT = 140MHz 1900MHz: fIN = 1830MHz, fOUT = 140MHz –68 –69 –47 dBc dBc dBc 3RF – 3LO Output Spurious (1/3 IF) Product (fIN = fLO + fOUT/3) 450MHz: fIN = 496.7MHz, fOUT = 69.9MHz 900MHz: fIN = 806.7MHz, fOUT = 140.1MHz 1900MHz: fIN = 1806.7MHz, fOUT = 140.1MHz –79 –76 –62 dBc dBc dBc Input 1dB Compression Point fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz –0.8 0 –2.2 dBm dBm dBm Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Each set of frequency conditions requires an appropriate test board. Note 3: Specifications over the –40°C to +85°C temperature range are assured by design, characterization and correlation with statistical process controls. U W Supply Current vs Supply Voltage UNITS (Test Circuit Shown in Figure 1) Shutdown Current vs Supply Voltage 1.0 25°C 85°C –40°C 25°C 85°C –40°C 0.8 CURRENT (µA) 11 CURRENT (mA) MAX Note 4: Operation over a wider frequency range is possible with reduced performance. Consult the factory for information and assistance. Note 5: SSB Noise Figure measurements are performed with a smallsignal noise source and bandpass filter on the RF input (downmixer) or output (upmixer), and no other RF input signal applied. TYPICAL DC PERFOR A CE CHARACTERISTICS 12 TYP 10 0.6 0.4 9 0.2 8 0.0 2.5 3 3.5 4 4.5 VOLTAGE (V) 5 5.5 5560 G01 2.5 3 3.5 4 4.5 VOLTAGE (V) 5 5.5 5560 G02 5560f 4 LT5560 U W TYPICAL AC PERFOR A CE CHARACTERISTICS 900MHz Upconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 140MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 760MHz, PLO = –2dBm, output measured at 900MHz, unless otherwise noted. (Test circuit shown in Figure 1) Conversion Gain, IIP3 and SSB NF vs RF Output Frequency 15 10 14 IIP3 10 8 11 6 10 SSB NF 9 5 4 8 GAIN 3 7 2 6 1 5 0 850 870 890 910 930 RF OUTPUT FREQUENCY (MHz) GAIN (dB), IIP3 (dBm) 12 NOISE FIGURE (dB) 7 17 IIP3 15 25°C 85°C –40°C 6 4 GAIN 2 4 950 –2 –10 –8 0 –6 –4 –2 LO INPUT POWER (dBm) 7 –10 2 GAIN (dB), IIP3 (dBm) 10 LO-OUT LO-IN 0 25°C 85°C –40°C IIP3 OUTPUT POWER (dBm/Tone) –10 –30 –6 –4 –2 LO INPUT POWER (dBm) 0 9 8 7 6 5 4 GAIN 3 2 –60 2 RFOUT, IM3 and IM2 vs IF Input Power (Two Input Tones) 12 –20 –8 5560 G05 Conversion Gain and IIP3 vs Supply Voltage 11 LEAKAGE (dBm) 11 10 5560 G04 0 RFOUT –20 IM3 25°C 85°C –40°C –40 IM2 –60 –80 1 0 2.5 –70 700 720 740 760 780 800 820 840 860 LO FREQUENCY (MHz) 3 4.5 4 3.5 VOLTAGE (V) 5 –100 –20 5.5 –10 –15 –5 IF INPUT POWER (dBm) 0 5560 G07 5560 G06 Gain Distribution at 900MHz 5560 G08 SSB Noise Figure Distribution at 900MHz IIP3 Distribution at 900MHz 60 50 13 12 8 LO-IN and LO-OUT Leakage vs LO Frequency –50 14 9 0 5560 G03 –40 25°C 85°C –40°C 16 13 25°C 85°C –40°C 8 SSB Noise Figure vs LO Input Power NOISE FIGURE (dB) 11 9 GAIN (dB), IIP3 (dBm) Conversion Gain and IIP3 vs LO Input Power 45 –45°C +25°C +90°C 60 –45°C +25°C +90°C 40 –45°C +25°C +90°C 50 40 30 20 DISTRIBUTION (%) DISTRIBUTION (%) DISTRIBUTION (%) 35 30 25 20 15 40 30 20 10 10 10 5 0 1.7 1.9 2.1 2.3 2.5 2.7 2.9 3.1 3.3 3.5 GAIN (dB) 5560 G09 0 0 7.8 8.2 8.6 9.0 9.4 IIP3 (dBm) 9.8 10.2 5560 G10 7.6 8.0 8.4 8.8 9.2 9.5 SSB NOISE FIGURE (dB) 10.0 10.4 5560 G11 5560f 5 LT5560 U W TYPICAL AC PERFOR A CE CHARACTERISTICS 450MHz Upconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 70MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 520MHz, PLO = –2dBm, output measured at 450MHz, unless otherwise noted. (Test circuit shown in Figure 3) Conversion Gain and IIP3 vs RF Output Frequency 14 IIP3 10 12 25°C 85°C –40°C 8 7 NOISE FIGURE (dB) 6 5 GAIN 4 3 RFOUT –10 11 10 9 8 7 –20 IM3 25°C 85°C –40°C –30 –40 IM2 –50 –60 –70 2 6 1 5 –80 0 350 4 350 –90 –20 400 450 500 RF OUTPUT FREQUENCY (MHz) 550 5560 G12 Conversion Gain and IIP3 vs LO Input Power 10 25°C 85°C –40°C 16 15 IIP3 14 8 6 4 550 GAIN 0 5560 G14 LO-IN and LO-OUT Leakage vs LO Frequency 0 25°C 85°C –40°C –10 –20 13 12 11 10 9 –30 –40 LO-OUT –50 8 2 –60 7 0 –10 –10 –15 –5 IF INPUT POWER (dBm) 5560 G13 SSB Noise Figure vs LO Input Power NOISE FIGURE (dB) 12 400 450 500 RF OUTPUT FREQUENCY (MHz) LEAKAGE (dBm) GAIN (dB), IIP3 (dBm) 9 0 25°C 85°C –40°C 13 OUTPUT POWER (dBm/Tone) 11 GAIN (dB), IIP3 (dBm) RFOUT, IM3 and IM2 vs IF Input Power (Two Input Tones) SSB Noise Figure vs RF Output Frequency –8 –6 –4 –2 LO INPUT POWER (dBm) 0 6 –10 2 5560 G15 –8 –2 –4 –6 LO INPUT POWER (dBm) 0 –70 350 2 5560 G16 LO-IN 400 450 500 550 LO FREQUENCY (MHz) 600 650 5560 G17 1900MHz Upconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 140MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 1760MHz, PLO = –2dBm, output measured at 1900MHz, unless otherwise noted. (Test circuit shown in Figure 1) Conversion Gain and IIP3 SSB Noise Figure RFOUT, IM3 and IM2 vs IF Input Power (Two Input Tones) vs RF Output Frequency vs RF Output Frequency 14 10 13 IIP3 12 8 NOISE FIGURE (dB) GAIN (dB), IIP3 (dBm) 9 7 6 5 4 3 25°C 85°C –40°C GAIN 2 RFOUT –10 11 10 9 8 7 6 1 1950 1900 1850 RF OUTPUT FREQUENCY (MHz) 2000 5560 018 4 1800 –20 –30 25°C 85°C –40°C IM3 –40 –50 IM2 –60 –70 5 0 –1 1800 0 25°C 85°C –40°C OUTPUT POWER (dBm/Tone) 11 1850 1900 1950 RF OUTPUT FREQUENCY (MHz) 2000 5560 G19 –80 –20 –10 –15 –5 IF INPUT POWER (dBm) 0 5560 G20 5560f 6 LT5560 U W TYPICAL AC PERFOR A CE CHARACTERISTICS 1900MHz Upconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 140MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 1760MHz, PLO = –2dBm, output measured at 1900MHz, unless otherwise noted. (Test circuit shown in Figure 1) Conversion Gain and IIP3 vs LO Input Power SSB Noise Figure vs LO Input Power 10 19 4 GAIN 2 0 –10 15 LEAKAGE (dBm) 25°C 85°C –40°C NOISE FIGURE (dB) GAIN (dB), IIP3 (dBm) 17 6 0 25°C 85°C –40°C IIP3 8 LO-IN and LO-OUT Leakage vs LO Frequency 13 11 –20 LO-OUT –30 LO-IN –40 9 –2 –4 –10 –8 –2 –4 –6 LO INPUT POWER (dBm) 0 7 –10 2 –8 5560 G21 –6 –4 –2 LO INPUT POWER (dBm) 0 –50 1660 2 5560 G22 1760 1710 1810 LO FREQUENCY (MHz) 1860 5560 G23 900MHz Downconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 900MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 760MHz, PLO = –2dBm, output measured at 140MHz, unless otherwise noted. (Test circuit shown in Figure 2) Conversion Gain, IIP3 and SSB NF vs RF Input Frequency IIP3 25°C 85°C –40°C 9 GAIN 3 7 1 5 –1 700 900 1000 1100 800 RF INPUT FREQUENCY (MHz) 8 2 3 1200 –2 –10 5560 G24 –8 –2 –4 –6 LO INPUT POWER (dBm) –10 –10 OUTPUT POWER (dBm) –20 –30 –40 LO-IN –60 600 700 900 1000 800 LO FREQUENCY (MHz) 1100 5560 G27 2 5560 G26 TA = 25°C fLO = 760MHz –60 fIF = 140MHz 3RF – 3LO fRF = 806.7MHz –40 –50 –60 2RF – 2LO –70 fRF = 830MHz –100 –20 0 –50 –20 –90 –6 –4 –2 LO INPUT POWER (dBm) 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) IFOUT fRF = 900MHz –30 –80 LO-OUT –8 5560 G25 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) 0 –70 11 7 – 10 2 0 10 –50 13 9 0 0 LEAKAGE (dBm) GAIN 4 LO-IN and LO-OUT Leakage vs LO Frequency –80 500 25°C 85°C –40°C 6 OUTPUT POWER (dBm) 5 11 15 GAIN (dB), IIP3 (dBm) SSB NF 25°C 85°C –40°C IIP3 10 13 7 17 12 NOISE FIGURE (dB) GAIN (dB), IIP3 (dBm) 9 15 SSB Noise Figure vs LO Input Power NOISE FIGURE (dB) 11 Conversion Gain and IIP3 vs LO Input Power TA = 25°C fLO = 760MHz fIF = 140MHz –15 –10 –5 RF INPUT POWER (dBm) –70 –80 –90 –100 0 5560 G28 2RF – 2LO fRF = 830MHz 3RF – 3LO fRF = 806.7MHz –110 –10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G29 5560f 7 LT5560 U W TYPICAL AC PERFOR A CE CHARACTERISTICS 900MHz Downconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 900MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 760MHz, PLO = –2dBm, output measured at 140MHz, unless otherwise noted. (Test circuit shown in Figure 2) Conversion Gain and IIP3 vs Supply Voltage IFOUT and IM3 vs RF Input Power (Two Input Tones) 12 10 11 IIP3 OUTPUT POWER (dBm/Tone) GAIN (dB), IIP3 (dBm) 9 8 7 6 25°C 85°C –40°C 5 GAIN 4 3 2 –10 IFOUT –20 –30 IM3 –40 –50 –60 –70 –80 1 0 2.5 25°C 85°C –40°C 0 10 3 4.5 4 3.5 VOLTAGE (V) 5 –90 –20 –18 –16 –14 –12 –10 –8 –6 –4 –2 0 RF INPUT POWER (dBm) 5560 G31 5.5 5560 G30 450MHz Downconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 450MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 520MHz, PLO = –2dBm, output measured at 70MHz, unless otherwise noted. (Test circuit shown in Figure 3) Conversion Gain and IIP3 SSB Noise Figure Conversion Gain, IIP3 and SSB NF vs LO Input Power vs LO Input Power vs RF Input Frequency 17 13 12 17 11 25°C 85°C –40°C IIP3 IIP3 15 10 13 8 9 GAIN 3 7 1 5 –1 350 400 450 500 RF INPUT FREQUENCY (MHz) GAIN 4 2 –2 –10 3 550 5560 G32 –8 –2 –4 –6 LO INPUT POWER (dBm) OUTPUT POWER (dBm) –10 –20 –30 –50 LO-IN 470 520 570 LO FREQUENCY (MHz) 620 5560 G35 –110 –20 0 2 5560 G34 –50 TA = 25°C fLO = 520MHz –60 fIF = 70MHz 3RF – 3LO fRF = 496.7MHz –50 –90 –60 –6 –4 –2 LO INPUT POWER (dBm) 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) IFOUT fRF = 450MHz –30 –70 –8 5560 G33 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) –10 LO-OUT 11 7 – 10 2 0 10 –40 13 9 0 0 LEAKAGE (dBm) 25°C 85°C –40°C 6 LO-IN and LO-OUT Leakage vs LO Frequency –70 420 NOISE FIGURE (dB) 5 11 OUTPUT POWER (dBm) GAIN (dB), IIP3 (dBm) SSB NF NOISE FIGURE (dB) 7 GAIN (dB), IIP3 (dBm) 15 25°C 85°C –40°C 9 2RF – 2LO fRF = 485MHz TA = 25°C fLO = 520MHz fIF = 70MHz –15 –10 –5 RF INPUT POWER (dBm) –70 –80 –90 2RF – 2LO fRF = 485MHz 3RF – 3LO fRF = 496.7MHz –100 0 5560 G36 –110 –10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G37 5560f 8 LT5560 U W TYPICAL AC PERFOR A CE CHARACTERISTICS 1900MHz Downconverting Mixer Application: VCC = 3V, ICC = 10mA, EN = 3V, TA = 25°C, fIN = 1900MHz, PIN = –20dBm (–20dBm/tone for 2-tone IIP3 tests, Δf = 1MHz), fLO = 1760MHz, PLO = –2dBm, output measured at 140MHz, unless otherwise noted. (Test circuit shown in Figure 2) Conversion Gain, IIP3 and SSB NF vs RF Input Frequency Conversion Gain and IIP3 vs LO Input Power 12 10 8 GAIN (dB) 6 GAIN 2 0 1700 1750 1800 1850 1900 1950 INPUT FREQUENCY (MHz) 4 0 0 –2 –8 5560 G38 –6 –4 –2 LO INPUT POWER (dBm) 0 2 –4 5560 G39 LO-IN and LO-OUT Leakage vs LO Frequency 17 0 15 –10 LEAKAGE (dBm) NOISE FIGURE (dB) 2 GAIN –2 –10 2000 4 2 SSB Noise Figure vs LO Input Power 13 11 –20 LO-OUT –30 LO-IN 9 7 – 10 –40 25°C 85°C –40°C –8 –6 –4 –2 LO INPUT POWER (dBm) 0 –50 1560 2 TA = 25°C fLO = 1760MHz –50 fIF = 140MHz OUTPUT POWER (dBm) 2RF – 2LO fRF = 1830MHz –70 3RF – 3LO fRF = 1806.7MHz –90 –20 1860 5560 G41 –40 IFOUT fRF = 1900MHz –30 –50 1660 1710 1760 1810 LO FREQUENCY (MHz) 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) 10 –10 1610 5560 G40 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) OUTPUT POWER (dBm) 25°C 85°C –40°C 6 IIP3 4 6 8 25°C 85°C –40°C IIP3 (dBm) GAIN, NF (dB), IIP3 (dBm) 10 8 IIP3 SSB NF TA = 25°C fLO = 1760MHz fIF = 140MHz –15 –10 –5 RF INPUT POWER (dBm) 2RF – 2LO fRF = 1830MHz –60 –70 3RF – 3LO fRF = 1806.7MHz –80 –90 0 5560 G42 –100 –10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G43 5560f 9 LT5560 U U U PI FU CTIO S LO –, LO+ (Pins 1, 8): Differential Inputs for the Local Oscillator Signal. The LO input impedance is approximately 180Ω, thus external impedance matching is required. The LO pins are internally biased to approximately 1V below VCC; therefore, DC blocking capacitors are required. The LT5560 is characterized and production tested with a single-ended LO drive, though a differential LO drive can be used. Each pin requires a DC current path to ground. Resistance to ground will cause a decrease in the mixer current. With 0Ω resistance, approximately 6mA of DC current flows out of each pin. For lowest LO leakage to the output, the DC resistance from each pin to ground should be equal. An impedance transformation is required to match the differential input to the desired source impedance. EN (Pin 2): Enable Pin. An applied voltage above 2V will activate the IC. For VEN below 0.3V, the IC will be shut down. If the enable function is not required, then this pin should be connected to VCC. The typical enable pin input current is 25µA for EN = 3V. The enable pin should not be allowed to float because the mixer may not turn on reliably. Note that at no time should the EN pin voltage be allowed to exceed VCC by more than 0.3V. VCC (Pin 7): Power Supply Pin for the Bias Circuits. Typical current consumption is 1.5mA. This pin should be externally bypassed with a 1nF chip capacitor. IN+, IN– (Pins 3, 4): Differential Inputs. These pins should be driven with a differential signal for optimum performance. OUT –, OUT+ (Pins 5, 6): Differential Outputs. An impedance transformation may be required to match the outputs. These pins require a DC current path to VCC . Exposed Pad (Pin 9): PGND. Circuit Ground Return for the Entire IC. This must be soldered to the printed circuit board ground plane. 5560f 10 LT5560 W BLOCK DIAGRA LO– 1 PGND 9 LO+ 8 INPUT BUFFER AMPLIFIER IN+ 3 6 OUT + IN– 4 5 OUT – DOUBLEBALANCED MIXER BIAS 2 7 EN VCC 5560 BD 5560f 11 LT5560 TEST CIRCUITS LOIN C3 C7 L5 C4 C5 VCC C9 1 EN IN T1 6 L1 1 2 4 3 L2 LO+ VCC EN 8 7 LT5560 3 2 C1 LO– 4 IN+ IN– OUT + OUT – PGND C8 C6 6 5 L4 OUT T2 L3 3 1 2 4 5 C10 R1 5560 F01 Component Values for fOUT = 900MHz, fIN = 140MHz and fLO = 760MHz REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER C1 22pF 0402 AVX 04025A220JAT L1, L2 18nH 1005 Toko LL1005-FH18NJ C3, C5 100pF 0402 AVX 04025A101JAT L3, L4 27nH 1005 Toko LL1005-FH27NJ C4 1pF 0402 AVX 04025A1R0BAT L5 12nH 1005 Toko LL1005-FH12NJ C6, C9 1nF 0402 AVX 04023C102JAT R1 3Ω 0402 C8 1µF 0603 Taiyo Yuden LMK107BJ105MA T1 1:1 Coilcraft WBC1-1TL C10 2.2pF 0402 AVX 04025A2R2BAT T2 4:1 TDK HHM1515B2 Note: C7 not used. Component Values for fOUT = 1900MHz, fIN = 140MHz and fLO = 1760MHz REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER C1 22pF 0402 AVX 04025A220JAT L1, L2 18nH 1005 Toko LL1005-FH18NJ C3 100pF 0402 AVX 04025A101JAT L3, L4 3.9nH 1005 Toko LL1005-FH3N9S C7 Toko LL1005-FH5N6S 1.5pF 0402 AVX 04025A1R5BAT L5 5.6nH 1005 C6, C9 1nF 0402 AVX 04023C102JAT R1 3Ω 0402 C8 1µF 0603 Taiyo Yuden LMK107BJ105MA T1 1:1 Coilcraft WBC1-1TL C10 1pF 0402 AVX 04025A1R0BAT T2 1:1 TDK HHM1525 Note: C4 and C5 are not used. Figure 1. Test Schematic for 900MHz and 1900MHz Upconverting Mixer Applications with 140MHz Input 5560f 12 LT5560 TEST CIRCUITS LOIN C3 C7 L5 C4 C5 VCC 1 EN IN T1 1 L1 4 2 5 C1 L2 LO+ EN VCC IN+ OUT+ 7 IN– OUT – PGND 5 L4 OUT T2 L3 6 C2 4 C8 C6 8 LT5560 3 2 3 LO– 3 4 2 1 6 R1 5560 F02 Component Values for fIN = 900MHz, fOUT = 140MHz and fLO = 760MHz REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER C1 2.2pF 0402 AVX 04025A2R2BAT L1, L2 0Ω 1005 0Ω Resistor C2 1.2pF 0402 AVX 04025A1R2BAT L3, L4 220nH 1608 Toko LL1608-FSR22J C3, C5 Toko LL1005-FH12NJ 100pF 0402 AVX 04025A101JAT L5 12nH 0402 C4 1pF 0402 AVX 04025A1R0BAT R1 3Ω 0402 C6 1nF 0402 AVX 04023C102JAT T1 1:1 TDK HHM1522B1 C8 1µF 0603 Taiyo Yuden LMK107BJ105MA T2 4:1 M/A-COM MABAES0061 Note: C7 not used. Component Values for fIN = 1900MHz, fOUT = 140MHz and fLO = 1760MHz REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER C1 1.0pF 0402 AVX 04025A1R0BAT L1, L2 0Ω 1005 0Ω Resistor C2 1.2pF 0402 AVX 04025A1R2BAT L3, L4 220nH 1608 Toko LL1608-FSR22J C3 100pF C7 1.5pF 0402 AVX 04025A101JAT L5 5.6nH 1005 Toko LL1005-FH5N6S 0402 AVX 04025A1R5BAT R1 3Ω 0402 C6 1nF 0402 AVX 04023C102JAT T1 2:1 TDK HHM1526 C8 1µF 0603 Taiyo Yuden LMK107BJ105MA T2 4:1 M/A-COM MABAES0061 Note: C4 and C5 are not used. Figure 2. Test Schematic for 900MHz and 1900MHz Downconverting Mixer Applications with 140MHz Input 5560f 13 LT5560 TEST CIRCUITS LOIN C3 L5 C4 C5 VCC EN IN C11 T1 6 L1 1 2 4 3 L2 LO+ EN VCC 4 7 IN+ OUT+ 6 IN– OUT – 5 PGND C8 C6 8 LT5560 3 2 C1 LO– L4 OUT T2 L3 3 4 2 1 6 C10 R1 5560 F03 Upconverting Mixer Component Values for fIN = 70MHz, fOUT = 450MHz and fLO = 520MHz REF DES VALUE SIZE PART NUMBER REF DES VALUE SIZE PART NUMBER C1 39pF 0402 AVX 04025390JAT L1, L2 33nH 1005 Toko LL1005-FH33NJ C3, C5, C6 1nF 0402 AVX 04023C102JAT L3, L4 68nH 1608 Toko LL1608-FS68NJ Toko LL1005-FH22NJ C4 1.5pF 0402 AVX 04025A1R5BAT L5 22nH 1005 C8 1µF 0603 Taiyo Yuden LMK107BJ105MA R1 3Ω 0402 C10 1.5pF 0402 AVX 04025A1R5BAT T1 1:1 Coilcraft WBC1-1TL T2 4:1 M/A-COM MABAES0061 Note: C11 is not used. Downconverting Mixer Component Values for fIN = 450MHz, fOUT = 70MHz and fLO = 520MHz REF DES VALUE SIZE PART NUMBER REF DES 1nF 0402 AVX 04023C102JAT L3, L4 1.5pF 0402 AVX 04025A1R5BAT C8 1µF 0603 C11 5.6pF 0603 0Ω 0402 0Ω Resistor C3, C5, C6 C4 L1, L2 VALUE SIZE PART NUMBER 0Ω 0402 0Ω Resistor L5 22nH 0402 Toko LL1005-FH22NJ Taiyo Yuden LMK107BJ105MA R1 3Ω 0402 AVX 06035A5R6BAT T1 1:1 Coilcraft WBC1-1TL T2 16:1 Coilcraft WBC16-1TL Note: C1 and C10 not used. Figure 3. Test Schematic for 450MHz Upconverting Mixer and Downconverting Mixer Applications 5560f 14 LT5560 U W U U APPLICATIO S I FOR ATIO The LT5560 consists of a double-balanced mixer, a common-base input buffer amplifier, and bias/enable circuits. The IC has been designed for frequency conversion applications up to 4GHz, though operation over a wider frequency range may be possible with reduced performance. For best performance, the input and output should be connected differentially. The LO input can be driven by a single-ended source with either low side or high side LO operation. The LT5560 is characterized and production tested using a single-ended LO drive. provided through the center-tap of an input transformer, as shown, or through matching inductors or chokes connected from pins 3 and 4 to ground. LT5560 INPUT Table 1. LT5560 Demo Board Descriptions DEMO BOARD NUMBER INPUT FREQ. (MHz) OUTPUT FREQ. (MHz) LO FREQ. (MHz) Upconverting, Cellular Band DC963B 50-190 850-940 530-930 Downconverting Cellular Band DC991A 710-1300 110-170 530-930 Downconverting, VHF Band DC1027A MIXER DESCRIPTION 115-295 3-60 180-310 Note: Consult factory for demo boards for UMTS, WLAN and other bands. Signal Input Port 3 C1 L2 4 IN – The quiescent DC current of the LT5560 can be adjusted from less than 4mA to approximately 13.5mA through the use of an external resistor. This functionality gives the user the ability to make application dependent trade-offs between IIP3 performance and DC current. Three demo boards, as described in Table 1, are available depending on the desired application. The listed input and output frequency ranges are based on measured 12dB return loss bandwidths and the LO port frequency ranges are based on 10dB return loss bandwidths. The general circuit topologies are shown in Figures 1, 2 and 3 for DC963B, DC991A and DC1027A, respectively. The board layouts are shown in Figures 23, 24 and 25. The low frequency board, DC1027A, can be reconfigured for upconverting applications. IN+ L1 T1 VBIAS R1 5560 F04 Figure 4. Input Port with Lowpass External Matching Topology The lowpass impedance matching topology shown may be used to transform the differential input impedance at pins 3 and 4 to match that of the signal source. The differential input impedances for several frequencies are listed in Table 2. Table 2. Input Signal Port Differential Impedance FREQUENCY (MHz) INPUT IMPEDANCE (Ω) 70 REFLECTION COEFFICIENT (ZO = 50Ω) MAG ANGLE (DEG.) 28.5 + j0.8 0.274 177 140 28.5 + j1.6 0.274 174 240 28.6 + j2.7 0.275 171 360 28.6 + j4.0 0.276 167 450 28.6 + j4.9 0.278 163 750 28.8 + j8.2 0.287 153 900 28.8 + j9.8 0.294 148 1500 29.1 + j16.3 0.328 138 1900 29.4 + j20.8 0.357 120 2150 29.6 + j23.6 0.376 114 2450 29.9 + j27.0 0.399 107 3600 31.7 + j42.1 0.499 86.2 Figure 4 shows a simplified schematic of the differential input signal port and an example topology for the external impedance matching circuit. Pins 3 and 4 each source up to 6mA of DC current. This current can be reduced by the addition of resistor R1 (adjustable mixer current is discussed in a later section). The DC ground path can be 5560f 15 LT5560 U W U U APPLICATIO S I FOR ATIO The following example demonstrates the design of a lowpass impedance transformation network for a signal input at 900MHz. The simplified input circuit is shown in Figure 5. For this example, the input transformer has a 1:1 impedance ratio, so RS = 50Ω. From Table 2, at 900MHz, the differential input impedance is: RL + jXINT = 28.8 + j9.8Ω. The internal reactance will be used as part of the impedance matching network. The matching circuit consists of additional external series inductance (L1 and L2) and a capacitance (C1) in parallel with the 50Ω source impedance. The external capacitance and inductance are calculated below. First, calculate the impedance transformation ratio (n) and the network Q: R 50 n= S = = 1 . 74 RL 28 . 8 The internal inductance has been accounted for by subtracting the internal reactance (XINT) from the total reactance (XL). Small inductance values may be realized using highimpedance printed transmission lines instead of lumped inductors. The equations above provide good starting values, though the values may need to be optimized to account for layout and component parasitics. LT5560 L1 XEXT/2 XINT/2 3 RS 50Ω C1 RL 28.1Ω L2 XEXT/2 XINT/2 4 5560 F05 Q= (n − 1) = 0 . 858 Figure 5. Small Signal Circuit for the Input Port Next, the capacitance and inductance can be calculated as follows: XC = RS = 58 . 3Ω Q C1 = 1 = 3 . 03pF ω • XC XL = RL • Q = 24.7Ω XEXT = XL – XINT = 14.9Ω L1 = L2 = L EXT X EXT = = 1 . 32nH 2 2ω 5560f 16 LT5560 Table 3 lists actual component values used on the LT5560 evaluation boards for impedance matching at various frequencies. The measured Input Return Loss vs Frequency performance is plotted for several of the cases in Figure 6. Table 3. Component Values for Input Matching CASE FREQ. (MHz) T1 C1 (pF) L1, L2 (nH) MATCH BW (@12dB RL) 1 10 WBC1-1TL 1:1 220 180 6-18 2 70 WBC1-1TL 1:1 39 33 29-102 3 140 WBC1-1TL 1:1 22 18 50-190 4 240 WBC1-1TL 1:1 15 12 115-295 5 4501 WBC1-1TL 1:1 NA 0 390-560 6 900 HHM1522B1 1:1 2.2 0 710-1630 7 1900 HHM1526 2:1 1 0 1660-2500 8 2450 HHM1520A2 2:1 1 0 1640-2580 9 3600 HHM1583B1 2:1 0.5 0 3330-3840 LO Input Port Figure 7 shows a simplified schematic of the LO input. The LO input connections drive the bases of the mixer transistors, while a 200Ω resistor across the inputs provides the impedance termination. The internal 1kΩ bias resistors are in parallel with the input resistor resulting in a net input DC resistance of approximately 180Ω. The pins are biased by an internally generated voltage at approximately 1V below VCC; thus external DC blocking capacitors are required. If desired, the LO inputs can be driven differentially. The required LO drive at the IC is 240mVRMS (typ) which can come from a 50Ω source or a higher impedance such as PECL. LT5560 1k C5 Note 1: Series 5.6pF capacitor is used at the input (see Figure 3). –5 RETURN LOSS (dB) 8 1 2 3 4 1 9 C7 –10 200Ω L5 7 5 1k LO+ VCC LOIN 50Ω C3 0 VBIAS LO– C4 5560 F07 6 –15 Figure 7. LO Input Schematic –20 –25 –30 10 100 1000 FREQUENCY (MHz) 4000 5560 F06 Figure 6. Input Return Loss vs Frequency for Different Matching Values 5560f 17 LT5560 U U W U APPLICATIO S I FOR ATIO Table 4. Single-Ended LO Input Impedance (Parallel Equivalent) FREQUENCY (MHz) INPUT IMPEDANCE (Ω) REFLECTION COEFFICIENT (ZO = 50Ω) MAG ANGLE (DEG.) 150 161 || –j679 0.529 –9.3 520 142 || –j275 0.494 –23.3 760 130 || –j192 0.475 –33.5 1660 74 || –j98 0.347 –74.5 1760 69 || –j94 0.330 –80.1 2040 60 || –j89 0.308 –90.1 2210 51 || –j91 0.266 –104 3150 50 || –j103 0.235 –104 3340 33 || –j41 0.472 –138 Table 5. Component Values for LO Input Matching CASE FREQ. (MHz) C4 (pF) L5 (nH) C7 (pF) C3, C5 (pF) MATCH BW (@12dB RL) 1 150 8.2 68 - 1000 120-180 2 250 4.7 47 - 1000 195-300 3 520 1.5 22 - 1000 390-605 4 760 1 12 - 100 590-890 5 1200 - 6.8 - 100 850-1430 1540-1890 6 1760 - 4.7 1 1001 7 2900 - 1 1 10 2690-3120 8 3150 - 0 - 10 2990-3480 Note 1: C5 is not used at 1760MHz 0 –5 4 RETURN LOSS (dB) Reactive matching from the LO source to the LO input is recommended to take advantage of the resulting voltage gain. To assist in matching, Table 4 lists the single-ended input impedances of the LO input port. Actual component values, for several LO frequencies, are listed in Table 5. Figure 8 shows the typical return loss response for each case. 6 8 –10 –15 1 2 3 –20 –25 –30 100 1000 FREQUENCY (MHz) 4000 5560 F08 Figure 8. Typical LO Input Return Loss vs Frequency for Different Matching Values 5560f 18 LT5560 U U W U APPLICATIO S I FOR ATIO Signal Output Port A simplified schematic of the output circuit is shown in Figure 9. The output pins, OUT + and OUT –, are internally connected to the collectors of the mixer transistors. These pins must be biased at the supply voltage, which can be applied through a transformer center-tap, impedance matching inductors, RF chokes, or pull-up resistors. With external resistor R1 = 3Ω (Figures 1 to 3), each OUT pin draws about 4.5mA of supply current. For optimum performance, these differential outputs should be combined externally through a transformer or balun. An equivalent small-signal model for the output is shown in Figure 10. The output impedance can be modeled as a 1.2kΩ resistor in parallel with a 0.7pF capacitor. For low frequency applications, the 0.7nH series bond-wire inductances can be ignored. The external components, C2, L3 and L4, form a lowpass impedance transformation network to match the mixer output impedance to the input impedance of transformer T2. The values for these components can be estimated LT5560 using the impedance parameters listed in Table 6 along with similar equations as used for the input matching network. As an example, at an output frequency of 140MHz and RL = 200Ω (using a 4:1 transformer for T2), n= R S 1082 = = 5 . 41 RL 200 Q= (n − 1) = 2 . 10 XC = RS = 515Ω Q C= 1 = 2 . 21pF ω • XC C2 = C – CINT = 1.51pF XL = RL • Q = 420Ω L3 = L 4 = XL = 239nH 2ω LT5560 OUT+ L3 0.7nH T2 OUT 6 6 OUT+ 1.2k RINT 1.2k 0.7pF CINT 0.7pF C2 OUT– 5560 F09 Figure 9. Output Port Schematic C10 L4 0.7nH 5 5 VCC VCC OUT – 5560 F10 Figure 10. Output Port Small-Signal Model with External Matching 5560f 19 LT5560 U U W U APPLICATIO S I FOR ATIO Table 6. Output Port Differential Impedance (Parallel Equivalent) REFLECTION COEFFICIENT (ZO = 50Ω) Table 7 lists actual component values used on the LT5560 evaluation boards for impedance matching at several frequencies. The measured output return loss vs frequency performance is plotted for several of the cases in Figure 11. FREQUENCY (MHz) OUTPUT IMPEDANCE (Ω) 70 1098 || –j3185 140 1082 || –j1600 0.912 –3.6 240 1082 || –j974 0.912 –5.9 360 1093 || –j646 0.913 –8.9 450 1083 || –j522 0.913 –11.0 750 1037 || –j320 0.910 –17.8 1 900 946 || –j269 0.903 –21.1 2 1500 655 || –j162 0.870 –34.5 1900 592 || –j122 0.865 –44.6 2150 662 || –j108 0.883 –50.0 2450 612 || –j95.7 0.879 –55.4 3600 188 || –j53.1 0.756 –88.7 MAG ANGLE (DEG.) 0.913 –1.8 Table 7. Component Values for Output Matching C10 (pF) MATCH BW (@12dB RL) 0 - 3-60 0 -1 3-60 1.5 220 - 110-170 MABAES0061 4:1 0.5 120 - 175-300 380 MABAES0061 4:1 - 68 - 290-490 6 450 MABAES0061 4:1 - 68 1.5 360-540 7 900 HHM1515B2 4:1 - 27 2.2 850-940 8 1900 HHM1525 1:1 - 3.9 1 1820-2000 FREQ. CASE (MHz) In cases where the calculated value of C2 is less than the internal output capacitance, capacitor C10 can be used to improve the impedance match. T2 C2 (pF) L3, L4 (nH) 10 WBC16-1TL 16:1 - 70 WBC16-1TL 16:1 - 3 140 MABAES0061 4:1 4 240 5 Note 1: A better 70MHz match can be realized by adding a shunt 180nH inductor at the C10 location. 0 RETURN LOSS (dB) –5 6 7 8 –10 –15 –20 3 4 –25 –30 0 500 1000 2000 1500 FREQUENCY (MHz) 2500 5560 F11 Figure 11. Output Return Loss vs Frequency for Different Matching Values 5560f 20 LT5560 U W U U APPLICATIO S I FOR ATIO Figure 12 shows a simplified schematic of the EN pin interface. The voltage necessary to turn on the LT5560 is 2V. To disable the chip, the enable voltage must be less than 0.3V. If the EN pin is allowed to float, the chip will tend to remain in its last operating state, thus it is not recommended that the enable function be used in this manner. If the shutdown function is not required, then the EN pin should be connected directly to VCC. The voltage at the EN pin should never exceed the power supply voltage (VCC) by more than 0.3V. If this should occur, the supply current could be sourced through the EN pin ESD diode, potentially damaging the IC. VCC LT5560 vs current of a 900MHz downconverting mixer is plotted in Figure 15. In this example, a 1nF capacitor has been placed in parallel to R1 for best noise figure. 14 TA = 25°C VCC = 3V 13 12 SUPPLY CURRENT (mA) Enable Interface 11 10 9 8 7 6 5 4 0 5 10 15 R1 (Ω) 20 25 30 5560 F13 Figure 13. Typical Supply Current vs R1 Value 14 EN 2 5560 F12 GAIN AND NF (dB), IIP3 (dBm) 12 60k 6 IIP3 4 GAIN 2 –2 Adjustable Supply Current Figure 13 shows the supply current as a function of R1. Note that the current will also be affected by parasitic resistance in the matching components. Figure 14 illustrates the effect of supply current on Gain, IIP3 and NF of a 900MHz upconverting mixer. The performance SSB NF 8 TA = 25°C fIF = 140MHz VCC = 3V PLO = –2dBm fLO = 760MHz 0 Figure 12. Enable Input Circuit 4 6 8 12 10 SUPPLY CURRENT (mA) 14 5560 F14 Figure 14. 900MHz Upconverting Mixer Gain, Noise Figure and IIP3 vs Supply Current 14 MEASURED WITH InF CAP ACROSS R1 12 GAIN AND NF (dB), IIP3 (dBm) The LT5560 offers a direct trade-off between power supply current and linearity. This capability allows the user to optimize the performance and power dissipation of the mixer for a particular application. The supply current can be adjusted by changing the value of resistor R1 at the center-tap of the input balun. For downconversion applications, a bypass capacitor in parallel with R1 may be desired to minimize noise figure. The bypass capacitor has a greater effect on noise figure at larger values of R1. In upmixer configurations, adding a capacitor across R1 has little effect. 10 SSB NF 10 8 IIP3 6 4 GAIN 2 TA = 25°C fIF = 140MHz VCC = 3V PLO = –2dBm fLO = 760MHz 0 –2 4 6 8 12 10 SUPPLY CURRENT (mA) 14 5560 F15 Figure 15. 900MHz Downconverting Mixer Gain, Noise Figure and IIP3 vs Supply Current 5560f 21 LT5560 U U W U APPLICATIO S I FOR ATIO 14 11 Application Examples IIP3 12 GAIN (dB), IIP3 (dBm) 9 SSB NF 7 fRF = 140MHz fIF = 10MHz fLO = 150MHz 5 IIP3 56 10 IIP2 54 52 8 50 fIF = 10MHz fLO = fRF + fIF GAIN 2 4 –8 0 –4 –2 –6 LO INPUT POWER (dBm) 2 5560 F17 Figure 17. LT5560 Performance in 140MHz Downconverting Mixer Application The LT5560 operation at higher frequencies is demonstrated in Figure 18, where the performance of a 3600MHz downconverting mixer is shown. The conversion gain, IIP3 and DSB NF are plotted for an RF input frequency range of 3300 to 3800MHz and an IF frequency of 450MHz. The circuit is the same topology as shown in Figure 2. 48 46 210 230 250 270 290 OUTPUT FREQUENCY (MHz) 11 44 310 5560 F16 Figure 16. LT5560 Performance in 240MHz Upconverting Mixer Application The performance in a 140MHz downconverting mixer application is plotted in Figure 17. In this case the gain, IIP3 and NF are shown as a function of LO power with an IF output frequency of 10MHz. The circuit topology for this case is shown in Figure 3. 10 GAIN NF (dB), IIP3 (dBm) 0 170 190 IIP2 (dBm) GAIN (dB), IIP3 (dBm) 12 4 1 –10 6 58 14 6 8 GAIN 3 Figure 16 demonstrates gain, IIP3 and IIP2 performance versus RF Output Frequency for the LT5560 when used as a 240MHz upconverting mixer. The input frequency is 10MHz, with an LO frequency of 250MHz. The circuit uses the topology shown in Figure 1. 10 NOISE FIGURE (dB) The LT5560 may be used as an upconverting or downconverting mixer in a wide variety of applications, in addition to those identified in the datasheet. The following examples illustrate the versatility of the LT5560. (The component values for each case can be found in Tables 3, 5 and 7). 9 DSB NF 8 7 IIP3 6 5 4 3 GAIN 2 1 3300 3400 3600 3700 3500 RF INPUT FREQUENCY (MHz) 3800 5560 F18 Figure 18. LT5560 Performance as a 3600MHz Downconverting Mixer 5560f 22 LT5560 U W U U APPLICATIO S I FOR ATIO Lumped Element Matching The applications described so far have employed external transformers or hybrid baluns to realize single-ended to differential conversions and, in some cases, impedance transformations. An alternate approach is to use lumpedelement baluns to realize the input or output matching networks. A lumped element balun topology is shown in Figure 19. The desired component values can be estimated using the equations below, where RA and RB are the terminating resistances on the unbalanced and balanced ports, respectively. Variable fC is the desired center frequency. (The resistances of the LT5560 input and output can be found in Tables 2 and 6). LO = CO = R A • RB 2 • π • fC 1 2 • π • fC • R A • RB The computed values are approximate, as they don’t account for the effects of parasitics of the IC and external components. Inductor LDC is used to provide a DC path to ground or to VCC depending on whether the circuit is used at the input or output of the LT5560. In some cases, it is desirable to make the value of LDC as large as practical to minimize loading on the circuit; however, the value can also be optimized to tune the impedance match. The shunt inductor, LO, provides the DC path for the other balanced port. Capacitor CDC may be required for DC blocking but can often be omitted if DC decoupling is not required. LO CO CDC RB LO RA LDC CO 5560 F19 Figure 19. Lumped Element Balun In some applications, CDC is useful for optimizing the impedance match. The circuit shown on page 1 illustrates the use of lumped element baluns. In this example, the LT5560 is used to convert a 900MHz input signal down to 140MHz using a 760MHz LO signal. For the 900MHz input, RA = 50Ω and RB = 28Ω (from Table 2). The actual values used for CO and LO are 4.7pF and 6.8nH, which agree very closely with the calculated values of 4.7pF and 6.6nH. The 15nH shunt inductor, in this case, has been used to optimize the impedance match, while the 100pF cap provides DC decoupling. At the 140MHz output, the values used for RA and RB are 50Ω and 1080Ω (from Table 6), respectively, which result in calculated values of CO = 4.9pF and LO = 265nH. These values are very close to the actual values of 4.7pF and 270nH. A shunt inductor (LDC) of 270nH is used here and the 33pF blocking cap has been used to optimize the impedance. 5560f 23 LT5560 U W U U APPLICATIO S I FOR ATIO Measured IFOUT and IM3 levels vs RF input power for the mixer with lumped element baluns are shown on page 1. Additional performance parameters vs RF input frequency are plotted in Figure 20. op-amp to demonstrate performance with an output frequency of 450KHz. Pull-up resistors R3 and R4 are used at the open-collector IF outputs instead of large inductors. The op-amp provides gain and converts the mixer differential outputs to single-ended. At low frequencies, the LO port can be easily matched with a shunt resistor and a DC blocking cap. This IF interface circuit can be used for signals up to 1MHz. 13 GAIN AND NF (dB), IIP3 (dBm) 12 IIP3 11 10 SSB NF Figure 21 shows an input match that uses a transformer to present a differential signal to the mixer. A possible alternative, shown in Figure 22, is to use a single-ended drive on one input pin, with the other pin grounded. This approach is more cost effective than the transformer, however, some performance is sacrificed. Another option is to use a lumped-element balun, which requires only one more component than the single-ended impedance match, but could provide better performance. Measured data for the examples below are summarized in Table 8. 9 8 7 6 GAIN 5 4 800 1000 850 950 900 INPUT FREQUENCY (MHz) 5560 F20 Figure 20. Performance of 900MHz Downconverting Mixer with Lumped Element Baluns Table 8. Low-Frequency Performance Low Frequency Applications At low IF frequencies, where transformers can be impractical due to their large size and cost, alternate methods can be used to achieve desired differential to single-ended conversions. The examples in Figures 21 and 22 use an LOIN 200.45MHz R2 160Ω fIN (MHz) fOUT (MHz) GC (dB) IIP3 (dBm) DSB NF (dB) ICC (mA) 200 0.45 9 3.8 11.6 14 90 0.45 6.8 3.3 22 18 C5 10nF C3 10nF 1 VEN RFIN 200MHz T1 1:1 L1 12nH C1 15pF WBC4-6TL 2 R1 3Ω L2 12nH 3 4 5V LO– 8 LO+ EN VCC + U1 LT5560 7 OUT+ IN– 5 OUT– PGND 9 R3 200Ω R4 200Ω 6 IN R8 5.1kΩ C6 1nF C12 1µF C11 1µF R5 200Ω C13 1µF + U2 LT6202 C8 1µF R9 5.1kΩ C14 1µF IFOUT R7 450kHz 51Ω – R6 200Ω 5560 F21 Figure 21. A 200MHz to 450KHz Downconverter with Active IF Interface 5560f 24 LT5560 U W U U APPLICATIO S I FOR ATIO LOIN 90.45MHz R2 160Ω C5 10nF C3 10nF 1 VEN RFIN 90MHz 2 L1 12nH C1 56pF 3 L2 82nH 4 5V LO– LO+ EN VCC IN+ IN– U1 LT5560 PGND 9 OUT+ OUT– 8 7 R8 5.1kΩ C6 1nF R3 200Ω R4 200Ω C11 1µF 6 C12 1µF 5 R5 200Ω C13 1µF + U2 LT6202 C8 1µF R9 5.1kΩ C14 1µF IFOUT R7 450kHz 51Ω – R6 200Ω 5560 F22 Figure 22. 90MHz Downconverter with a Low Cost Discrete Balun Input and a 450kHz Active IF Interface Figure 23. Upconverting Mixer Evaluation Board (DC963B)—See Table 1 5560f 25 LT5560 U TYPICAL APPLICATIO S Figure 24. Downconverting Mixer Evaluation Board (DC991A)—See Table 1 Figure 25. HF/VHF/UHF Upconverting or Downconverting Mixer Evaluation Board (DC1027A)—See Table 1 5560f 26 LT5560 U PACKAGE DESCRIPTIO DD8 Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698) 0.675 ±0.05 3.5 ±0.05 1.65 ±0.05 (2 SIDES) 2.15 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS R = 0.115 TYP 5 3.00 ±0.10 (4 SIDES) 0.38 ± 0.10 8 1.65 ± 0.10 (2 SIDES) PIN 1 TOP MARK (NOTE 6) (DD8) DFN 1203 0.200 REF 0.75 ±0.05 0.00 – 0.05 4 0.25 ± 0.05 1 0.50 BSC 2.38 ±0.10 (2 SIDES) BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON TOP AND BOTTOM OF PACKAGE 5560f Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 27 LT5560 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT5511 High Linearity Upconverting Mixer RF Output to 3GHz, 17dBm IIP3, Integrated LO Buffer LT5512 1KHz to 3GHz High Signal Level Downconverting Mixer 20dBm IIP3, Integrated LO Buffer, HF/VHF/UHF Optimized LT5514 Ultralow Distortion, IF Amplifier/ADC Driver with Digitally Controlled Gain 850MHz Bandwidth, 47dBm OIP3 at 100MHz, 10.5dB to 33dB Gain Control Range LT5515 1.5GHz to 2.5GHz Direct Conversion Quadrature 20dBm IIP3, Integrated LO Quadrature Generator Demodulator LT5516 0.8GHz to 1.5GHz Direct Conversion Quadrature 21.5dBm IIP3, Integrated LO Quadrature Generator Demodulator LT5517 40MHz to 900MHz Quadrature Demodulator 21dBm IIP3, Integrated LO Quadrature Generator LT5518 1.5GHz to 2.4GHz High Linearity Direct Quadrature Modulator 22.8dBm OIP3 at 2GHz, –158.2dBm/Hz Noise Floor, 50Ω Single-Ended LO and RF Ports, 4-Ch W-CDMA ACPR = –64dBc at 2.14GHz LT5519 0.7GHz to 1.4GHz High Linearity Upconverting Mixer 17.1dBm IIP3 at 1GHz, Integrated RF Output Transformer with 50Ω Matching, Single-Ended LO and RF Ports Operation LT5520 1.3GHz to 2.3GHz High Linearity Upconverting Mixer 15.9dBm IIP3 at 1.9GHz, Integrated RF Output Transformer with 50Ω Matching, Single-Ended LO and RF Ports Operation LT5521 10MHz to 3700MHz High Linearity Upconverting Mixer 24.2dBm IIP3 at 1.95GHz, NF = 12.5dB, 3.15V to 5.25V Supply, Single-Ended LO Port Operation LT5522 400MHz to 2.7GHz High Signal Level Downconverting Mixer 4.5V to 5.25V Supply, 25dBm IIP3 at 900MHz, NF = 12.5dB, 50Ω Single-Ended RF and LO Ports LT5524 Low Power, Low Distortion ADC Driver with Digitally Programmable Gain 450MHz Bandwidth, 40dBm OIP3, 4.5dB to 27dB Gain Control LT5525 High Linearity, Low Power Downconverting Mixer 50Ω Single-Ended LO and RF Ports, 17.6 dBm IIP3 at 1900MHz, ICC = 28mA LT5526 High Linearity, Low Power Active Mixer 3V to 5.3V Supply, 16.5dBm IIP3, 100kHz to 2GHz RF, NF = 11dB, ICC = 28mA, –65dBm LO-RF Leakage LT5527 400MHz to 3.7GHz High Signal Level Downconverting Mixer IIP3 = 23.5dBm and NF = 12.5dB at 1900MHz, 4.5V to 5.25V Supply, ICC = 78mA, Single-Ended LO and RF Ports LT5528 1.5GHz to 2.4GHz High Linearity Direct Quadrature Modulator 21.8dBm OIP3 at 2GHz, –159.3dBm/Hz Noise Floor, 50Ω, 0.5VDC Baseband Interface, 4-Ch W-CDMA ACPR = –66dBc at 2.14GHz LT5568 700MHz to 1050MHz High Linearity Direct Quadrature Modulator 22.9dBm OIP3, –160dBm/Hz Noise Floor, –46dBc Image Rejection, –43dBm LO Leakage Infrastructure RF Power Detectors LTC®5505 RF Power Detectors with >40dB Dynamic Range 300MHz to 3GHz, Temperature Compensated, 2.7V to 6V Supply LTC5507 100kHz to 1000MHz RF Power Detector 100kHz to 1GHz, Temperature Compensated, 2.7V to 6V Supply LTC5508 300MHz to 7GHz RF Power Detector 44dB Dynamic Range, Temperature Compensated, SC70 Package LTC5509 300MHz to 3GHz RF Power Detector 36dB Linear Dynamic Range, Low Power Consumption, SC70 Package LTC5532 300MHz to 7GHz Precision RF Power Detector Precision VOUT Offset Control, Adjustable Gain and Offset LT5534 50MHz to 3GHz Log RF Power Detector with 60dB Dynamic Range ±1dB Output Variation over Temperature, 38ns Response Time LTC5536 Precision 600MHz to 7GHz RF Detector with Fast Comparater 25ns Response Time, Comparator Reference Input, Latch Enable Input, –26dBm to +12dBm Input Range LT5537 Wide Dynamic Range Log RF/IF Detector Low Frequency to 800MHz, 83dB Dynamic Range, 2.7V to 5.25V Supply 5560f 28 Linear Technology Corporation LT 0406 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2006