LT5560

LT5560 0.01MHz to 4GHz Low Power Active Mixer FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO 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 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. 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. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIO S ■ ■ ■ ■ ■ ■ ■ Portable Wireless CATV/DBS Receivers WiMAX Radios PHS Basestations RF Instrumentation Microwave Data Links VHF/UHF 2-Way Radios TYPICAL APPLICATIO Low Cost 900MHz Downconverting Mixer 2.7V TO 5.3V LOIN 1µF 760MHz 10 100pF 100pF 15nH 1 4.7pF EN 2 3 RFIN 900MHz 100pF 6.8nH 4.7pF 4 IN– PGND 9 OUT – 5 LO– EN IN+ U1 LT5560 LO+ VCC OUT+ 8 7 6 270nH 270nH 4.7pF 270nH IFOUT 33pF 140MHz 1nF POWER LEVEL (dBm/Tone) 0 –10 –20 –30 –40 –50 –60 –70 IM3 TA = 25°C VCC = 3V ICC = 13.3mA fLO = 760MHz fIF = 140MHz 0 IFOUT 15nH 6.8nH 4.7pF 5560 TA01 U IFOUT and IM3 Levels vs RF Input Power –80 –20 –18 –16 –14 –12 –10 –8 –6 –4 –2 RF INPUT POWER (dBm) 5560 TA02 U U 5560f 1 LT5560 ABSOLUTE (Note 1) AXI U RATI GS PACKAGE/ORDER I FOR ATIO TOP VIEW LO– 1 EN 2 IN+ 3 IN– 4 9 8 7 6 5 LO+ VCC OUT+ OUT – 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 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 LT5560EDD DD PART MARKING 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 shown in Figure 1. (Note 3) PARAMETER Power Supply Requirements (VCC) Supply Voltage Supply Current Shutdown Current Enable (EN) Low = Off, High = On EN Input High Voltage (On) EN Input Low Voltage (Off) Enable Pin Input Current Turn On Time Turn Off Time EN = 3V EN = 0.3V VCC = 3V, R1 = 3Ω EN = 0.3V, VCC = 3V CONDITIONS VCC = 3V, EN = 3V, TA = 25°C, unless otherwise noted. Test circuit MIN 2.7 TYP 3 10 0.1 2 0.3 25 0.1 2 5 MAX 5.3 12 10 UNITS V mA µA V V µA µA µs µs AC ELECTRICAL CHARACTERISTICS PARAMETER Signal Input Frequency Range (Note 4) LO Input Frequency Range (Note 4) Signal Output Frequency Range (Note 4) CONDITIONS (Notes 2 and 3) MIN TYP < 4000 < 4000 < 4000 MAX UNITS MHz MHz MHz 5560f Requires External Matching Requires External Matching Requires External Matching 2 U W U U WW W LT5560 AC ELECTRICAL CHARACTERISTICS PARAMETER Signal Input Return Loss LO Input Return Loss Signal Output Return Loss LO Input Power CONDITIONS Z = 50Ω, External Match Z = 50Ω, External Match Z = 50Ω, External Match 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) MIN TYP 15 15 15 –6 to 1 MAX UNITS dB dB dB 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 Conversion Gain CONDITIONS fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz TA = – 40°C to 85°C, fOUT = 900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz fIN = 70MHz, fOUT = 450MHz fIN = 140MHz, fOUT = 900MHz fIN = 140MHz, fOUT = 1900MHz MIN TYP 2.7 2.4 1.2 – 0.015 9.6 9.0 8.0 46 47 30 8.8 9.3 10.3 69 64 64 –63 –54 –36 –44 –41 –36 0.4 –2.8 –0.8 MAX UNITS dB dB dB dB/°C dBm dBm dBm dBm dBm dBm dB dB dB dB dB dB dBm dBm dBm dBm dBm dBm dBm dBm dBm Conversion Gain vs Temperature Input 3rd Order Intercept Input 2nd Order Intercept Single Sideband Noise Figure IN to LO Isolation (with LO Applied) LO to IN Leakage LO to OUT Leakage Input 1dB Compression Point 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 Conversion Gain CONDITIONS fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz TA = – 40°C to 85°C, fIN = 900MHz fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz MIN TYP 2.7 2.6 2.3 – 0.015 10.1 9.7 5.6 10.5 10.1 10.8 MAX UNITS dB dB dB dB/°C dBm dBm dBm dB dB dB 5560f Conversion Gain vs Temperature Input 3rd Order Intercept Single Sideband Noise Figure 3 LT5560 AC ELECTRICAL CHARACTERISTICS PARAMETER IN to LO Isolation (with LO Applied) CONDITIONS fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz 450MHz: fIN = 485MHz, fOUT = 70MHz 900MHz: fIN = 830MHz, fOUT = 140MHz 1900MHz: fIN = 1830MHz, fOUT = 140MHz 450MHz: fIN = 496.7MHz, fOUT = 69.9MHz 900MHz: fIN = 806.7MHz, fOUT = 140.1MHz 1900MHz: fIN = 1806.7MHz, fOUT = 140.1MHz fIN = 450MHz, fOUT = 70MHz fIN = 900MHz, fOUT = 140MHz fIN = 1900MHz, fOUT = 140MHz 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) MIN TYP 52 52 25 –52 –57 –37 –47 –63 –24 –68 –69 –47 –79 –76 –62 –0.8 0 –2.2 MAX UNITS dB dB dB dBm dBm dBm dBm dBm dBm dBc dBc dBc dBc dBc dBc dBm dBm dBm LO to IN Leakage LO to OUT Leakage 2RF – 2LO Output Spurious (Half IF) Product (fIN = fLO + fOUT/2) 3RF – 3LO Output Spurious (1/3 IF) Product (fIN = fLO + fOUT/3) Input 1dB Compression Point 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. 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 Supply Current vs Supply Voltage 12 25°C 85°C –40°C CURRENT (µA) 1.0 11 CURRENT (mA) 10 9 0.2 8 2.5 3 3.5 4 4.5 VOLTAGE (V) 5 5.5 5560 G01 4 UW (Test Circuit Shown in Figure 1) Shutdown Current vs Supply Voltage 25°C 85°C –40°C 0.8 0.6 0.4 0.0 2.5 3 3.5 4 4.5 VOLTAGE (V) 5 5.5 5560 G02 5560f LT5560 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 11 10 9 GAIN (dB), IIP3 (dBm) 8 7 6 5 4 3 2 1 0 850 870 890 910 930 RF OUTPUT FREQUENCY (MHz) GAIN 25°C 85°C –40°C SSB NF IIP3 15 14 13 GAIN (dB), IIP3 (dBm) 12 NOISE FIGURE (dB) 11 10 9 8 7 6 5 4 950 5560 G03 TYPICAL AC PERFOR A CE CHARACTERISTICS Conversion Gain and IIP3 vs LO Input Power 10 8 6 4 2 0 –2 –10 IIP3 NOISE FIGURE (dB) LO-IN and LO-OUT Leakage vs LO Frequency 0 –10 GAIN (dB), IIP3 (dBm) –20 –30 –40 –50 –60 –70 700 720 740 760 780 800 820 840 860 LO FREQUENCY (MHz) 5560 G06 OUTPUT POWER (dBm/Tone) LEAKAGE (dBm) LO-OUT LO-IN Gain Distribution at 900MHz 60 50 DISTRIBUTION (%) 40 30 20 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) 0 –45°C +25°C +90°C DISTRIBUTION (%) 45 40 35 30 25 20 15 10 DISTRIBUTION (%) UW 5560 G09 SSB Noise Figure vs LO Input Power 17 16 15 25°C 85°C –40°C 25°C 85°C –40°C GAIN 14 13 12 11 10 9 8 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G04 7 –10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G05 Conversion Gain and IIP3 vs Supply Voltage 12 11 10 9 8 7 6 5 4 3 2 1 0 2.5 3 4.5 4 3.5 VOLTAGE (V) 5 5.5 5560 G07 RFOUT, IM3 and IM2 vs IF Input Power (Two Input Tones) 0 RFOUT IM3 25°C 85°C –40°C IM2 –60 25°C 85°C –40°C IIP3 –20 –40 GAIN –80 –100 –20 –10 –15 –5 IF INPUT POWER (dBm) 0 5560 G08 IIP3 Distribution at 900MHz –45°C +25°C +90°C 60 50 40 30 20 10 0 7.8 8.2 8.6 9.0 9.4 IIP3 (dBm) 9.8 10.2 5560 G10 SSB Noise Figure Distribution at 900MHz –45°C +25°C +90°C 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 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 11 10 9 GAIN (dB), IIP3 (dBm) NOISE FIGURE (dB) 8 7 6 5 4 3 2 1 0 350 400 450 500 RF OUTPUT FREQUENCY (MHz) 550 5560 G12 TYPICAL AC PERFOR A CE CHARACTERISTICS SSB Noise Figure vs RF Output Frequency 14 IIP3 13 12 25°C 85°C –40°C 11 10 9 8 7 6 5 4 350 400 450 500 RF OUTPUT FREQUENCY (MHz) 25°C 85°C –40°C OUTPUT POWER (dBm/Tone) GAIN Conversion Gain and IIP3 vs LO Input Power 12 10 GAIN (dB), IIP3 (dBm) 8 6 4 2 0 –10 GAIN 25°C 85°C –40°C 16 15 IIP3 NOISE FIGURE (dB) 14 13 12 11 10 9 8 7 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G15 LEAKAGE (dBm) 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 11 10 9 GAIN (dB), IIP3 (dBm) 8 7 6 5 4 3 2 1 0 –1 1800 1950 1900 1850 RF OUTPUT FREQUENCY (MHz) 2000 5560 018 IIP3 OUTPUT POWER (dBm/Tone) NOISE FIGURE (dB) 25°C 85°C –40°C GAIN 6 UW RFOUT, IM3 and IM2 vs IF Input Power (Two Input Tones) 0 –10 –20 –30 –40 –50 –60 –70 –80 550 5560 G13 RFOUT 25°C 85°C –40°C IM3 IM2 –90 –20 –10 –15 –5 IF INPUT POWER (dBm) 0 5560 G14 SSB Noise Figure vs LO Input Power 25°C 85°C –40°C 0 –10 –20 –30 –40 –50 –60 LO-IN and LO-OUT Leakage vs LO Frequency LO-OUT LO-IN 6 –10 –8 –2 –4 –6 LO INPUT POWER (dBm) 0 2 5560 G16 –70 350 400 450 500 550 LO FREQUENCY (MHz) 600 650 5560 G17 14 13 12 11 10 9 8 7 6 5 4 1800 25°C 85°C –40°C 0 RFOUT –10 –20 –30 –40 –50 –60 –70 IM2 25°C 85°C –40°C IM3 1850 1900 1950 RF OUTPUT FREQUENCY (MHz) 2000 5560 G19 –80 –20 –10 –15 –5 IF INPUT POWER (dBm) 0 5560 G20 5560f LT5560 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 10 IIP3 8 GAIN (dB), IIP3 (dBm) NOISE FIGURE (dB) 6 4 2 0 –2 –4 –10 25°C 85°C –40°C GAIN 17 15 13 11 9 7 –10 19 TYPICAL AC PERFOR A CE CHARACTERISTICS SSB Noise Figure vs LO Input Power 25°C 85°C –40°C LEAKAGE (dBm) –8 –2 –4 –6 LO INPUT POWER (dBm) 0 5560 G21 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 11 9 GAIN (dB), IIP3 (dBm) 7 5 3 1 –1 700 25°C 85°C –40°C SSB NF IIP3 15 13 GAIN (dB), IIP3 (dBm) NOISE FIGURE (dB) 11 9 GAIN 7 5 3 1200 5560 G24 6 4 2 0 –2 –10 25°C 85°C –40°C GAIN NOISE FIGURE (dB) 900 1000 1100 800 RF INPUT FREQUENCY (MHz) LO-IN and LO-OUT Leakage vs LO Frequency 0 –10 OUTPUT POWER (dBm) –20 LEAKAGE (dBm) –30 –40 –50 –60 –70 –80 500 600 700 LO-OUT LO-IN 10 0 –10 –20 –30 –40 –50 –60 –80 –90 900 1000 800 LO FREQUENCY (MHz) 1100 5560 G27 3RF – 3LO fRF = 806.7MHz OUTPUT POWER (dBm) UW 2 LO-IN and LO-OUT Leakage vs LO Frequency 0 –10 –20 LO-OUT LO-IN –40 –30 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G22 –50 1660 1760 1710 1810 LO FREQUENCY (MHz) 1860 5560 G23 Conversion Gain and IIP3 vs LO Input Power 12 10 8 IIP3 15 17 SSB Noise Figure vs LO Input Power 25°C 85°C –40°C 13 11 9 –8 –2 –4 –6 LO INPUT POWER (dBm) 0 2 5560 G25 7 – 10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G26 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) –50 IFOUT fRF = 900MHz 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) TA = 25°C fLO = 760MHz –60 fIF = 140MHz –70 –80 –90 –100 3RF – 3LO fRF = 806.7MHz 2RF – 2LO fRF = 830MHz 2RF – 2LO –70 fRF = 830MHz TA = 25°C fLO = 760MHz fIF = 140MHz –15 –10 –5 RF INPUT POWER (dBm) 0 5560 G28 –100 –20 –110 –10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G29 5560f 7 LT5560 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 12 11 10 GAIN (dB), IIP3 (dBm) 9 8 7 6 5 4 3 2 1 0 2.5 3 4.5 4 3.5 VOLTAGE (V) 5 5.5 5560 G30 TYPICAL AC PERFOR A CE CHARACTERISTICS OUTPUT POWER (dBm/Tone) 25°C 85°C –40°C GAIN 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 13 IIP3 11 GAIN (dB), IIP3 (dBm) 9 7 5 GAIN 3 1 –1 350 7 5 3 550 5560 G32 GAIN (dB), IIP3 (dBm) SSB NF 11 9 6 4 2 0 –2 –10 25°C 85°C –40°C GAIN NOISE FIGURE (dB) 25°C 85°C –40°C 400 450 500 RF INPUT FREQUENCY (MHz) LO-IN and LO-OUT Leakage vs LO Frequency 0 –10 OUTPUT POWER (dBm) –20 –30 –40 –50 –60 –70 420 LO-OUT LO-IN 10 –10 –30 –50 –70 –90 OUTPUT POWER (dBm) LEAKAGE (dBm) 470 520 570 LO FREQUENCY (MHz) 8 UW IIP3 17 15 13 NOISE FIGURE (dB) 620 5560 G35 IFOUT and IM3 vs RF Input Power (Two Input Tones) 10 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –20 –18 –16 –14 –12 –10 –8 –6 –4 –2 0 RF INPUT POWER (dBm) 5560 G31 IM3 25°C 85°C –40°C IFOUT 12 IIP3 10 17 15 8 25°C 85°C –40°C 13 11 9 –8 –2 –4 –6 LO INPUT POWER (dBm) 0 2 5560 G33 7 – 10 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G34 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) –50 IFOUT fRF = 450MHz 3RF – 3LO fRF = 496.7MHz 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) TA = 25°C fLO = 520MHz –60 fIF = 70MHz –70 –80 –90 –100 –110 –10 2RF – 2LO fRF = 485MHz 3RF – 3LO fRF = 496.7MHz 2RF – 2LO fRF = 485MHz TA = 25°C fLO = 520MHz fIF = 70MHz –15 –10 –5 RF INPUT POWER (dBm) 0 5560 G36 –110 –20 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G37 5560f LT5560 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 12 SSB NF 10 GAIN, NF (dB), IIP3 (dBm) 8 6 4 2 0 1700 1750 25°C 85°C –40°C GAIN (dB) IIP3 8 6 4 2 0 –2 –10 25°C 85°C –40°C GAIN 10 TYPICAL AC PERFOR A CE CHARACTERISTICS GAIN 1800 1850 1900 1950 INPUT FREQUENCY (MHz) SSB Noise Figure vs LO Input Power 17 0 15 NOISE FIGURE (dB) LEAKAGE (dBm) 13 11 9 7 – 10 25°C 85°C –40°C –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G40 IFOUT, 2 × 2 and 3 × 3 Spurs vs RF Input Power (Single Input Tone) 10 IFOUT fRF = 1900MHz OUTPUT POWER (dBm) –40 –10 OUTPUT POWER (dBm) –30 2RF – 2LO fRF = 1830MHz –50 –70 3RF – 3LO fRF = 1806.7MHz –90 –20 –15 –10 –5 RF INPUT POWER (dBm) UW Conversion Gain and IIP3 vs LO Input Power IIP3 8 6 4 IIP3 (dBm) 2 0 –2 –4 2000 5560 G38 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G39 LO-IN and LO-OUT Leakage vs LO Frequency –10 –20 LO-OUT –30 LO-IN –40 –50 1560 1610 1660 1710 1760 1810 LO FREQUENCY (MHz) 1860 5560 G41 2 × 2 and 3 × 3 Spurs vs LO Input Power (Single Input Tone) TA = 25°C fLO = 1760MHz –50 fIF = 140MHz –60 –70 –80 –90 –100 –10 3RF – 3LO fRF = 1806.7MHz 2RF – 2LO fRF = 1830MHz TA = 25°C fLO = 1760MHz fIF = 140MHz 0 5560 G42 –8 –6 –4 –2 LO INPUT POWER (dBm) 0 2 5560 G43 5560f 9 LT5560 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. 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. IN+, IN– (Pins 3, 4): Differential Inputs. These pins should be driven with a differential signal for optimum performance. 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. 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 . 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. Exposed Pad (Pin 9): PGND. Circuit Ground Return for the Entire IC. This must be soldered to the printed circuit board ground plane. 10 U U U 5560f LT5560 BLOCK DIAGRA W PGND 9 LO– 1 LO+ 8 IN+ 3 IN– 4 DOUBLEBALANCED MIXER INPUT BUFFER AMPLIFIER 6 OUT + 5 OUT – BIAS 2 EN 7 5560 BD VCC 5560f 11 LT5560 TEST CIRCUITS LOIN C3 C7 L5 C4 C5 VCC C8 C9 1 2 3 LO– EN LT5560 IN+ IN– OUT + LO+ VCC 8 7 6 L3 C6 EN IN 6 T1 1 2 4 3 R1 C1 L2 L1 T2 3 1 C10 5 OUT 4 PGND OUT – 5 L4 2 4 5560 F01 Component Values for fOUT = 900MHz, fIN = 140MHz and fLO = 760MHz REF DES C1 C3, C5 C4 C6, C9 C8 C10 Note: C7 not used. VALUE 22pF 100pF 1pF 1nF 1µF 2.2pF SIZE 0402 0402 0402 0402 0603 0402 PART NUMBER AVX 04025A220JAT AVX 04025A101JAT AVX 04025A1R0BAT AVX 04023C102JAT Taiyo Yuden LMK107BJ105MA AVX 04025A2R2BAT REF DES L1, L2 L3, L4 L5 R1 T1 T2 VALUE 18nH 27nH 12nH 3Ω 1:1 4:1 SIZE 1005 1005 1005 0402 Coilcraft WBC1-1TL TDK HHM1515B2 PART NUMBER Toko LL1005-FH18NJ Toko LL1005-FH27NJ Toko LL1005-FH12NJ Component Values for fOUT = 1900MHz, fIN = 140MHz and fLO = 1760MHz REF DES C1 C3 C7 C6, C9 C8 C10 VALUE 22pF 100pF 1.5pF 1nF 1µF 1pF SIZE 0402 0402 0402 0402 0603 0402 PART NUMBER AVX 04025A220JAT AVX 04025A101JAT AVX 04025A1R5BAT AVX 04023C102JAT Taiyo Yuden LMK107BJ105MA AVX 04025A1R0BAT REF DES L1, L2 L3, L4 L5 R1 T1 T2 VALUE 18nH 3.9nH 5.6nH 3Ω 1:1 1:1 SIZE 1005 1005 1005 0402 Coilcraft WBC1-1TL TDK HHM1525 PART NUMBER Toko LL1005-FH18NJ Toko LL1005-FH3N9S Toko LL1005-FH5N6S 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 C7 C3 L5 C5 C4 VCC 1 2 3 LO– EN LT5560 IN+ IN– OUT+ OUT – 6 C2 4 5 PGND LO+ VCC 8 7 L3 3 L4 2 1 T2 4 OUT C6 C8 EN IN 1 T1 4 2 5 3 R1 C1 L2 L1 6 5560 F02 Component Values for fIN = 900MHz, fOUT = 140MHz and fLO = 760MHz REF DES C1 C2 C3, C5 C4 C6 C8 Note: C7 not used. VALUE 2.2pF 1.2pF 100pF 1pF 1nF 1µF SIZE 0402 0402 0402 0402 0402 0603 PART NUMBER AVX 04025A2R2BAT AVX 04025A1R2BAT AVX 04025A101JAT AVX 04025A1R0BAT AVX 04023C102JAT Taiyo Yuden LMK107BJ105MA REF DES L1, L2 L3, L4 L5 R1 T1 T2 VALUE 0Ω 220nH 12nH 3Ω 1:1 4:1 SIZE 1005 1608 0402 0402 TDK HHM1522B1 M/A-COM MABAES0061 PART NUMBER 0Ω Resistor Toko LL1608-FSR22J Toko LL1005-FH12NJ Component Values for fIN = 1900MHz, fOUT = 140MHz and fLO = 1760MHz REF DES C1 C2 C3 C7 C6 C8 VALUE 1.0pF 1.2pF 100pF 1.5pF 1nF 1µF SIZE 0402 0402 0402 0402 0402 0603 PART NUMBER AVX 04025A1R0BAT AVX 04025A1R2BAT AVX 04025A101JAT AVX 04025A1R5BAT AVX 04023C102JAT Taiyo Yuden LMK107BJ105MA REF DES L1, L2 L3, L4 L5 R1 T1 T2 VALUE 0Ω 220nH 5.6nH 3Ω 2:1 4:1 SIZE 1005 1608 1005 0402 TDK HHM1526 M/A-COM MABAES0061 PART NUMBER 0Ω Resistor Toko LL1608-FSR22J Toko LL1005-FH5N6S 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 LO– EN IN C11 6 T1 1 2 4 3 R1 5560 F03 LO+ VCC LT5560 OUT+ OUT – 8 7 6 L3 C6 C8 2 3 EN IN+ IN– L1 C1 T2 3 4 C10 6 OUT L2 4 5 L4 PGND 2 1 Upconverting Mixer Component Values for fIN = 70MHz, fOUT = 450MHz and fLO = 520MHz REF DES C1 C3, C5, C6 C4 C8 C10 VALUE 39pF 1nF 1.5pF 1µF 1.5pF SIZE 0402 0402 0402 0603 0402 PART NUMBER AVX 04025390JAT AVX 04023C102JAT AVX 04025A1R5BAT Taiyo Yuden LMK107BJ105MA AVX 04025A1R5BAT REF DES L1, L2 L3, L4 L5 R1 T1 T2 Note: C11 is not used. VALUE 33nH 68nH 22nH 3Ω 1:1 4:1 SIZE 1005 1608 1005 0402 Coilcraft WBC1-1TL M/A-COM MABAES0061 PART NUMBER Toko LL1005-FH33NJ Toko LL1608-FS68NJ Toko LL1005-FH22NJ Downconverting Mixer Component Values for fIN = 450MHz, fOUT = 70MHz and fLO = 520MHz REF DES C3, C5, C6 C4 C8 C11 L1, L2 VALUE 1nF 1.5pF 1µF 5.6pF 0Ω SIZE 0402 0402 0603 0603 0402 PART NUMBER AVX 04023C102JAT AVX 04025A1R5BAT Taiyo Yuden LMK107BJ105MA AVX 06035A5R6BAT 0Ω Resistor T2 Note: C1 and C10 not used. 16:1 Coilcraft WBC16-1TL REF DES L3, L4 L5 R1 T1 VALUE 0Ω 22nH 3Ω 1:1 SIZE 0402 0402 0402 Coilcraft WBC1-1TL PART NUMBER 0Ω Resistor Toko LL1005-FH22NJ Figure 3. Test Schematic for 450MHz Upconverting Mixer and Downconverting Mixer Applications 5560f 14 LT5560 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. 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. Table 1. LT5560 Demo Board Descriptions MIXER DESCRIPTION Upconverting, Cellular Band Downconverting Cellular Band Downconverting, VHF Band DEMO BOARD NUMBER DC963B DC991A DC1027A INPUT FREQ. (MHz) 50-190 710-1300 115-295 OUTPUT FREQ. (MHz) 850-940 110-170 3-60 LO FREQ. (MHz) 530-930 530-930 180-310 Note: Consult factory for demo boards for UMTS, WLAN and other bands. Signal Input Port 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 U 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 T1 L1 3 C1 L2 4 IN – R1 VBIAS IN+ 5560 F04 W U U 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) 70 140 240 360 450 750 900 1500 1900 2150 2450 3600 INPUT IMPEDANCE (Ω) 28.5 + j0.8 28.5 + j1.6 28.6 + j2.7 28.6 + j4.0 28.6 + j4.9 28.8 + j8.2 28.8 + j9.8 29.1 + j16.3 29.4 + j20.8 29.6 + j23.6 29.9 + j27.0 31.7 + j42.1 REFLECTION COEFFICIENT (ZO = 50Ω) MAG 0.274 0.274 0.275 0.276 0.278 0.287 0.294 0.328 0.357 0.376 0.399 0.499 ANGLE (DEG.) 177 174 171 167 163 153 148 138 120 114 107 86.2 5560f 15 LT5560 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 Q= (n − 1) = 0 . 858 Next, the capacitance and inductance can be calculated as follows: XC = C1 = RS = 58 . 3Ω Q 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 16 U 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 3 RS 50Ω C1 L2 XEXT/2 4 RL 28.1Ω XINT/2 XINT/2 5560 F05 W U U Figure 5. Small Signal Circuit for the Input Port 5560f 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 1 2 3 4 5 6 7 8 9 FREQ. (MHz) 10 70 140 240 4501 900 1900 2450 3600 T1 WBC1-1TL 1:1 WBC1-1TL 1:1 WBC1-1TL 1:1 WBC1-1TL 1:1 WBC1-1TL 1:1 HHM1522B1 1:1 HHM1526 2:1 HHM1520A2 2:1 HHM1583B1 2:1 C1 (pF) 220 39 22 15 NA 2.2 1 1 0.5 L1, L2 (nH) 180 33 18 12 0 0 0 0 0 MATCH BW (@12dB RL) 6-18 29-102 50-190 115-295 390-560 710-1630 1660-2500 1640-2580 3330-3840 1k C5 8 LO+ 1k LT5560 VBIAS 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. Note 1: Series 5.6pF capacitor is used at the input (see Figure 3). 0 –5 RETURN LOSS (dB) –10 6 –15 1 3 4 5 7 9 LOIN 50Ω C3 VCC L5 1 C7 C4 LO– 200Ω 2 5560 F07 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 APPLICATIO S I FOR ATIO 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. Table 4. Single-Ended LO Input Impedance (Parallel Equivalent) FREQUENCY (MHz) 150 520 760 1660 1760 2040 2210 3150 3340 INPUT IMPEDANCE (Ω) 161 || –j679 142 || –j275 130 || –j192 74 || –j98 69 || –j94 60 || –j89 51 || –j91 50 || –j103 33 || –j41 REFLECTION COEFFICIENT (ZO = 50Ω) MAG 0.529 0.494 0.475 0.347 0.330 0.308 0.266 0.235 0.472 ANGLE (DEG.) –9.3 –23.3 –33.5 –74.5 RETURN LOSS (dB) 0 –5 4 –10 –15 –20 –25 –30 100 1 2 3 6 8 –80.1 –90.1 –104 –104 –138 18 U Table 5. Component Values for LO Input Matching CASE 1 2 3 4 5 6 7 8 FREQ. (MHz) 150 250 520 760 1200 1760 2900 3150 C4 (pF) 8.2 4.7 1.5 1 L5 (nH) 68 47 22 12 6.8 4.7 1 0 C7 (pF) 1 1 C3, C5 (pF) 1000 1000 1000 100 100 1001 10 10 MATCH BW (@12dB RL) 120-180 195-300 390-605 590-890 850-1430 1540-1890 2690-3120 2990-3480 Note 1: C5 is not used at 1760MHz 1000 FREQUENCY (MHz) 4000 5560 F08 W U U Figure 8. Typical LO Input Return Loss vs Frequency for Different Matching Values 5560f LT5560 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 OUT+ 6 1.2k 0.7pF 5 VCC OUT– 5560 F09 Figure 9. Output Port Schematic U 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= Q= XC = C= R S 1082 = = 5 . 41 RL 200 W U U (n − 1) = 2 . 10 RS = 515Ω Q 1 = 2 . 21pF ω • XC C2 = C – CINT = 1.51pF XL = RL • Q = 420Ω L3 = L 4 = XL = 239nH 2ω LT5560 0.7nH 6 OUT+ RINT 1.2k CINT 0.7pF 0.7nH 5 OUT – 5560 F10 L3 T2 OUT C2 L4 VCC C10 Figure 10. Output Port Small-Signal Model with External Matching 5560f 19 LT5560 APPLICATIO S I FOR ATIO FREQUENCY (MHz) 70 140 240 360 450 750 900 1500 1900 2150 2450 3600 OUTPUT IMPEDANCE (Ω) 1098 || –j3185 1082 || –j1600 1082 || –j974 1093 || –j646 1083 || –j522 1037 || –j320 946 || –j269 655 || –j162 592 || –j122 662 || –j108 612 || –j95.7 188 || –j53.1 MAG 0.913 0.912 0.912 0.913 0.913 0.910 0.903 0.870 0.865 0.883 0.879 0.756 Table 6. Output Port Differential Impedance (Parallel Equivalent) REFLECTION COEFFICIENT (ZO = 50Ω) ANGLE (DEG.) –1.8 –3.6 –5.9 –8.9 –11.0 –17.8 –21.1 –34.5 –44.6 –50.0 –55.4 –88.7 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. 0 –5 RETURN LOSS (dB) –10 –15 –20 3 –25 –30 0 500 1000 2000 1500 FREQUENCY (MHz) 2500 5560 F11 Figure 11. Output Return Loss vs Frequency for Different Matching Values 20 U 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. Table 7. Component Values for Output Matching FREQ. CASE (MHz) 1 2 3 4 5 6 7 8 10 70 140 240 380 450 900 1900 C2 (pF) 1.5 0.5 L3, L4 (nH) 0 0 220 120 68 68 27 3.9 C10 (pF) -1 1.5 2.2 1 MATCH BW (@12dB RL) 3-60 3-60 110-170 175-300 290-490 360-540 850-940 1820-2000 T2 WBC16-1TL 16:1 WBC16-1TL 16:1 MABAES0061 4:1 MABAES0061 4:1 MABAES0061 4:1 MABAES0061 4:1 HHM1515B2 4:1 HHM1525 1:1 Note 1: A better 70MHz match can be realized by adding a shunt 180nH inductor at the C10 location. 6 7 8 4 5560f W U U LT5560 APPLICATIO S I FOR ATIO Enable Interface 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 SUPPLY CURRENT (mA) EN 2 60k GAIN AND NF (dB), IIP3 (dBm) 5560 F12 Figure 12. Enable Input Circuit Adjustable Supply Current 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. 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 GAIN AND NF (dB), IIP3 (dBm) U 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 13 12 11 10 9 8 7 6 5 4 0 5 10 15 R1 (Ω) 20 25 30 5560 F13 W U U TA = 25°C VCC = 3V Figure 13. Typical Supply Current vs R1 Value 14 12 10 8 6 IIP3 4 2 0 –2 4 6 TA = 25°C fIF = 140MHz VCC = 3V PLO = –2dBm fLO = 760MHz 8 12 10 SUPPLY CURRENT (mA) 14 5560 F14 SSB NF GAIN Figure 14. 900MHz Upconverting Mixer Gain, Noise Figure and IIP3 vs Supply Current 14 12 10 8 6 4 2 0 –2 4 6 TA = 25°C fIF = 140MHz VCC = 3V PLO = –2dBm fLO = 760MHz 8 12 10 SUPPLY CURRENT (mA) 14 5560 F15 MEASURED WITH InF CAP ACROSS R1 SSB NF IIP3 GAIN Figure 15. 900MHz Downconverting Mixer Gain, Noise Figure and IIP3 vs Supply Current 5560f 21 LT5560 APPLICATIO S I FOR ATIO Application Examples 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). 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. 14 12 GAIN (dB), IIP3 (dBm) 10 8 6 4 2 0 170 190 fIF = 10MHz fLO = fRF + fIF GAIN IIP3 IIP2 58 56 54 52 50 48 46 44 310 5560 F16 GAIN (dB), IIP3 (dBm) GAIN NF (dB), IIP3 (dBm) 210 230 250 270 290 OUTPUT FREQUENCY (MHz) 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. 22 U 11 IIP3 9 12 NOISE FIGURE (dB) 14 7 fRF = 140MHz fIF = 10MHz fLO = 150MHz GAIN SSB NF 10 5 8 3 6 1 –10 4 –8 0 –4 –2 –6 LO INPUT POWER (dBm) 2 5560 F17 W U U 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. 11 10 9 8 7 6 5 4 3 2 1 3300 3400 3600 3700 3500 RF INPUT FREQUENCY (MHz) 3800 5560 F18 IIP2 (dBm) DSB NF IIP3 GAIN Figure 18. LT5560 Performance as a 3600MHz Downconverting Mixer 5560f LT5560 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). R A • RB 2 • π • fC 1 2 • π • fC • R A • RB LO CO CDC LO RA LDC CO RB LO = CO = 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. U 5560 F19 W U U 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 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. 13 12 GAIN AND NF (dB), IIP3 (dBm) IIP3 11 10 9 8 7 6 5 4 800 GAIN SSB NF 850 950 900 INPUT FREQUENCY (MHz) 1000 5560 F20 Figure 20. Performance of 900MHz Downconverting Mixer with Lumped Element Baluns 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 C3 10nF 1 VEN RFIN 200MHz T1 1:1 C1 15pF WBC4-6TL R1 3Ω L1 12nH L2 12nH 2 3 LO– EN IN + U1 LT5560 4 IN– PGND 9 Figure 21. A 200MHz to 450KHz Downconverter with Active IF Interface 24 U 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. 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. Table 8. Low-Frequency Performance fIN (MHz) 200 90 fOUT (MHz) 0.45 0.45 GC (dB) 9 6.8 IIP3 (dBm) 3.8 3.3 DSB NF (dB) 11.6 22 ICC (mA) 14 18 C5 10nF 5V 8 LO+ VCC OUT+ 7 6 C12 1µF R3 200Ω R4 200Ω C6 1nF R5 200Ω C13 1µF R8 5.1kΩ R9 5.1kΩ C14 1µF IFOUT R7 450kHz 51Ω C8 1µF C11 1µF W U U + U2 LT6202 5 OUT– – R6 200Ω 5560 F21 5560f LT5560 APPLICATIO S I FOR ATIO LOIN 90.45MHz R2 160Ω C3 10nF 1 VEN RFIN 90MHz C1 56pF L1 12nH L2 82nH 2 3 LO– EN IN+ IN– U1 LT5560 LO+ VCC OUT+ OUT– 8 7 6 C12 1µF 5 R3 200Ω R4 200Ω C6 1nF R5 200Ω C13 1µF R8 5.1kΩ R9 5.1kΩ C14 1µF C8 1µF 4 PGND 9 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 U C5 10nF 5V C11 1µF W U U + U2 LT6202 IFOUT R7 450kHz 51Ω – R6 200Ω 5560 F22 5560f 25 LT5560 TYPICAL APPLICATIO S U 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 PACKAGE DESCRIPTIO U DD8 Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698) 0.675 ± 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 0.38 ± 0.10 8 3.00 ± 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) (DD8) DFN 1203 3.5 ± 0.05 1.65 ± 0.05 (2 SIDES) 2.15 ± 0.05 1.65 ± 0.10 (2 SIDES) 0.200 REF 0.75 ± 0.05 4 0.25 ± 0.05 2.38 ± 0.10 (2 SIDES) 1 0.50 BSC 0.00 – 0.05 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 Infrastructure LT5511 LT5512 LT5514 LT5515 LT5516 LT5517 LT5518 LT5519 LT5520 LT5521 LT5522 LT5524 LT5525 LT5526 LT5527 LT5528 LT5568 High Linearity Upconverting Mixer 1KHz to 3GHz High Signal Level Downconverting Mixer Ultralow Distortion, IF Amplifier/ADC Driver with Digitally Controlled Gain RF Output to 3GHz, 17dBm IIP3, Integrated LO Buffer 20dBm IIP3, Integrated LO Buffer, HF/VHF/UHF Optimized 850MHz Bandwidth, 47dBm OIP3 at 100MHz, 10.5dB to 33dB Gain Control Range DESCRIPTION COMMENTS 1.5GHz to 2.5GHz Direct Conversion Quadrature 20dBm IIP3, Integrated LO Quadrature Generator Demodulator 0.8GHz to 1.5GHz Direct Conversion Quadrature 21.5dBm IIP3, Integrated LO Quadrature Generator Demodulator 40MHz to 900MHz Quadrature Demodulator 1.5GHz to 2.4GHz High Linearity Direct Quadrature Modulator 0.7GHz to 1.4GHz High Linearity Upconverting Mixer 1.3GHz to 2.3GHz High Linearity Upconverting Mixer 10MHz to 3700MHz High Linearity Upconverting Mixer 400MHz to 2.7GHz High Signal Level Downconverting Mixer Low Power, Low Distortion ADC Driver with Digitally Programmable Gain High Linearity, Low Power Downconverting Mixer High Linearity, Low Power Active Mixer 400MHz to 3.7GHz High Signal Level Downconverting Mixer 1.5GHz to 2.4GHz High Linearity Direct Quadrature Modulator 700MHz to 1050MHz High Linearity Direct Quadrature Modulator RF Power Detectors with >40dB Dynamic Range 100kHz to 1000MHz RF Power Detector 300MHz to 7GHz RF Power Detector 300MHz to 3GHz RF Power Detector 300MHz to 7GHz Precision RF Power Detector 50MHz to 3GHz Log RF Power Detector with 60dB Dynamic Range Precision 600MHz to 7GHz RF Detector with Fast Comparater Wide Dynamic Range Log RF/IF Detector 21dBm IIP3, Integrated LO Quadrature Generator 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 17.1dBm IIP3 at 1GHz, Integrated RF Output Transformer with 50Ω Matching, Single-Ended LO and RF Ports Operation 15.9dBm IIP3 at 1.9GHz, Integrated RF Output Transformer with 50Ω Matching, Single-Ended LO and RF Ports Operation 24.2dBm IIP3 at 1.95GHz, NF = 12.5dB, 3.15V to 5.25V Supply, Single-Ended LO Port Operation 4.5V to 5.25V Supply, 25dBm IIP3 at 900MHz, NF = 12.5dB, 50Ω Single-Ended RF and LO Ports 450MHz Bandwidth, 40dBm OIP3, 4.5dB to 27dB Gain Control 50Ω Single-Ended LO and RF Ports, 17.6 dBm IIP3 at 1900MHz, ICC = 28mA 3V to 5.3V Supply, 16.5dBm IIP3, 100kHz to 2GHz RF, NF = 11dB, ICC = 28mA, –65dBm LO-RF Leakage IIP3 = 23.5dBm and NF = 12.5dB at 1900MHz, 4.5V to 5.25V Supply, ICC = 78mA, Single-Ended LO and RF Ports 21.8dBm OIP3 at 2GHz, –159.3dBm/Hz Noise Floor, 50Ω, 0.5VDC Baseband Interface, 4-Ch W-CDMA ACPR = –66dBc at 2.14GHz 22.9dBm OIP3, –160dBm/Hz Noise Floor, –46dBc Image Rejection, –43dBm LO Leakage 300MHz to 3GHz, Temperature Compensated, 2.7V to 6V Supply 100kHz to 1GHz, Temperature Compensated, 2.7V to 6V Supply 44dB Dynamic Range, Temperature Compensated, SC70 Package 36dB Linear Dynamic Range, Low Power Consumption, SC70 Package Precision VOUT Offset Control, Adjustable Gain and Offset ±1dB Output Variation over Temperature, 38ns Response Time 25ns Response Time, Comparator Reference Input, Latch Enable Input, –26dBm to +12dBm Input Range Low Frequency to 800MHz, 83dB Dynamic Range, 2.7V to 5.25V Supply RF Power Detectors LTC®5505 LTC5507 LTC5508 LTC5509 LTC5532 LT5534 LTC5536 LT5537 5560f 28 Linear Technology Corporation (408) 432-1900 ● FAX: (408) 434-0507 ● LT 0406 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 www.linear.com © LINEAR TECHNOLOGY CORPORATION 2006