As seen in Microwaves& RF magazine June 2006 issue LTCC Launches Miniature, Wideband, Low-Cost Mixers l ENGINEERING STAFF Mini-Circuits, P.O. Box 350166, Brooklyn, NY 11235-0003; (718) 934-4500, FAX: (718) 332-4661, Internet: www.minicircuits.com. By combining sophisticated circuit techniques with advanced LTCC material technology, the SIM line of extremely compact, extremely broadband mixers is born. ow-temperature co-fired ceramic (LTCC) circuit materials lend themselves to highperformance components in extremely small footprints. They also are the foundation for a new series of broadband, low-cost mixers from a company synonymous with mixers, Mini-Circuits (Brooklyn, NY). The new mixer line employs patented techniques using LTCC and advanced semiconductor technologies to cover bandwidths from 750 MHz to 15 GHz.1 The versatile mixers can be used as upconverters and downconverters; their wide frequency ranges makes them suitable for a host of applications. The new model SIM-153+ LTCC double-balanced mixer (Fig. 1, left), for example, measures just 0.2 ⫻ 0.18 ⫻ 0.08 in. (5.1 ⫻ 4.6 ⫻ 2.1 mm), considerably smaller than commercial FET- and diode-based mixers. Model SIM-153+, unlike some semiconductor mixers, is passive and requires no bias energy; it is insensitive to electrostatic discharge (ESD). It operates with RF signals from 3.4 to 15.0 GHz and has an intermediate-frequency (IF) range of DC to 4.0 GHz. Since it can be used as both and upconverter and downconverter, it can be used in a wide range of commercial and military applications. It is also RoHS compliant for use in systems requiring lead-free components. The entire structure of the mixer (Fig. 1, right), except for the diodes, is implemented in multiple layers of LTCC circuitry. With strong adhesion between its multiple layers, LTCC is inherently rugged and hermetic. L R In contrast to existing mixI ers, the new SIM mixers occupy very little PCB real estate and are easier to mount and connect. For example, dropin and open-carrier mixers require cut-outs in the PCB 1. The tiny but broadband SIM-153+ mixer operates with for mounting. The open-car- LO and RF signals from 3.5 to 15.0 GHz and offers IF sigrier mixer package must be nals from DC to 4.0 GHz (left). All of the mixer’s circuitry secured with screws, a labor- except the diode quad is fabricated on low-loss LTCC intensive process. The new material (right). ® P.O.Box 350166, Brooklyn, New York 11235-0003 (718) 934-4500 Fax (718) 332-4661 See us on the web at: www.minicircuits.com Mini-Circuits ISO 9001 & ISO 14001 Certified SIM-153+ Conversion-loss variable IF LO = 8000 MHz Conversion loss—dB Conversion loss—dB 20 +7 dBm 12 +4 dBm 10 8 +10 dBm 6 +4 dBm 10 +10 dBm 5 0 0 1000 2000 3000 4000 Intermediate frequency—MHz +7 dBm 15 4 5000 0 1000 2000 3000 4000 Intermediate frequency—MHz 5000 2. Conversion loss was measured with a fixed LO frequency of 8 GHz and three different LO drive levels (left) as well as with the three different LO drive levels at a fixed LO frequency of 15 GHz (right). SIM mixers are considerably smaller than either of these mixer options. In fact, the SIM mixers are about onehalf the size of the MCA1 series2 of mixers from Mini-Circuits, which have been successfully used in many systems. The SIM mixers are smaller than ceramic-packaged integrated-circuit (IC) mixers and only slightly larger than their plastic-packaged counterparts. The performance of the SIM-153+ mixer model is summarized in the table. It is designed for nominal local-oscillator (LO) power of +7 dBm, but is versatile enough to deliver fine performance over a wide range of LO levels. The mixer was tested at three different LO levels in order to simulate the effects of LO variations on mixer performance. The conversion loss at nominal LO power (+7 dBm) and above is less than 10.5 dB to an IF of 4.0 GHz. While some slight variations in conversion-loss perfor- mance occur at different LO levels when operating with a fixed LO frequency of 8 GHz (Fig. 2, left), the conversion-loss performance is remarkably well behaved when tested with an RF input frequency of 15 GHz for LO levels of +4, +7, and +10 dBm (Fig. 2, right). Even when tested over wide temperature variations (from –55 to +100ºC), the mixer’s conversion-loss performance referenced to room temperature (+25ºC) remains for the most part within a tight ±0.5-dB window (Fig. 3). The mixer was put to the test over this broad temperature range to reveal any performance flaws; it is actually specified over a “narrower” temperature range of –40 to +85ºC. When tested at various LO levels and a fixed IF, the SIM-153+ mixer maintained low conversion loss of typically 6 dB through 9 GHz and typically 8 dB through 15 GHz. Because the IF bandwidth of these mixers is so wide 2.0 1.0 Isolation—dB 1.5 +100°C +25°C 0.5 0 –0.5 –1.0 3000 –55°C 6000 9000 12000 RF port frequency—MHz 15000 3. Variations in conversion loss with temperature were evaluated at –55, +25, and +100ºC. (DC to 4.0 GHz), they are useful in systems requiring multiple frequency conversions (such as a multiple-downconversion receiver or multiple-upconversion transmitter), with a higher IF used for the first conversion stage. The mixer provides enough flexibility that it can handle downconversion of signals as high as 15 GHz to standard IFs, such as 70 MHz, or upconversion of that same IF to microwave frequencies. Port-to-port isolation is one of the key performance parameters for an RF/microwave mixer, with high isolation showing good circuit design. When the SIM-153+ mixer was evaluated for LO-to-RF port isolation at three different LO levels, it exhibited excellent performance of typically 40 dB from 3.4 to 5.0 GHz and 28 to 43 dB over the rest of the frequency range. For specific application frequencies, such as the classic 3.7-to-4.2-GHz satelliteSIM-153+ L-R isolation vs. temperature SIM-153+ Conversion loss delta—dB, REF: C.L. at 25°C C.L. delta—dB | MIXERS | 14 SIM-153+ Conversion-loss variable IF LO = 15,000 MHz 60 55 50 45 40 35 30 25 20 3000 +100°C +25°C –55°C 6000 9000 12000 LO frequency—MHz 15000 4. The LO-to-RF-port isolation of the SIM-153+ mixer was tested at –55, +25, and +100ºC. SIM-153+ L-I isolation 40 LO = +4 dBm L-I isolation—dB L-I isolation—dB | MIXERS | 40 33 26 LO = +7 dBm 19 LO = +10 dBm 12 3000 6000 9000 12000 Frequency—MHz SIM-153+ L-I isolation vs. temperature +100°C 15000 35 –55°C 30 25 +25°C 20 15 10 3000 6000 9000 12000 Frequency—MHz 15000 5. The LO-to-IF isolation was tested at three different LO levels (left) and temperatures of –55, +25, and +100ºC (right). communications (satcom) band, the SIM-153+ provides typical isolation of 40 dB. Such high isolation reduces the amount of additional filtering that must be provided with the mixer. It is also invaluable when two mixers are used to realize a single-sideband (SSB) mixer or in-phase (I) and quadrature (Q) modulator/demodulator. In addition to excellent unit-to-unit performance repeatability, the LTCC construction also yields minimal performance variations as a function of frequency. When the LO-to-RF isolation was evaluated at three temperatures ranging from –55 to 100ºC, the isolation was found to remain within a ±2 dB window across the full frequency range when the LO frequency was swept from 3.5 to 15.0 GHz (Fig. 4). Isolation from the LO port to the IF port is essential in preventing LO frequencies from leaking or mixing with IF signals. Again, poor isolation can increase the requirements (and the cost) for additional filtering. When evaluated with LO levels of +4, +7, and +10 dBm from 3.5 to 15.0 GHz, the SIM153+ mixer dropped to a low point at about 8 GHz (about 13 dB) but maintained LO-to-IF isolation of well above 19 dB for all three LO power levels and for frequencies beyond 9 GHz (Fig. 5, left). When the LO-to-IF isolation was tested at three different operating temperatures (Fig. 5, right), the isolation was within ±1 dB over the entire temperature range. The linearity of the SIM-153+ mixer, in terms of third-order intercept (IP3) performance, was evaluat- The SIM-153+ mixer at a glance PARAMETER RF/LO frequency range 3.4 to 15.0 GHz Intermediate DC to 4.0 GHz frequency range Conversion loss (typical) 8.0 dB L-R isolation (typical) 36 dB L-I isolation (typical) 25 dB Compression, P1dB +1 dBm Operating temperature range -40 to +85ºC Storage temperature range -55 to +100ºC ed at three different LO levels and found to vary typically from +6 to +18 dBm from 4 to 9 GHz. To verify the consistency of the LTCC process used to fabricate the mixers, five different units were measured for IP3 performance across the same frequency range and found to vary by less than ±1 dB. Since the peaks and valleys in the IP3 performance are repeatable from unit to unit, the mixer can be counted upon to deliver high IP3 performance of +18 dBm at 4.8 GHz and +15 dBm at 9 GHz. The SIM-153+ and other SIM mixers are built to withstand severe electrostatic-discharge (ESD) environments even under conditions that would damage semiconductor mixers. For example, the SIM mixers pass 1000-V ESD for Human Body Model (HBM) or Class 1C testing. In contrast, monolithic semiconductor mixers are typically only Class 1A (250-V capability) for HBM testing. The SIM mixers also pass 100 V ESD for Machine Model (Class M2) testing. Published data are not available for semiconductor mixers regarding ESD Machine Model sensitivity levels. The SIM mixers are priced at about one-half to one-third the price of semiconductor mixers, even though they provide much wider bandwidths. The wide bandwidth of the SIM-153+ mixer makes it of great interest for instrumentation and military applications. A single mixer model such as the SIM153+ can be used in multiple commercial applications as a way of simplifying inventory and product bill of materials (BOMs). Mini-Circuits’ LTCC mixers have been tested extensively and qualified for environmental conditions such as humidity, shock, and vibration.3 To evaluate the durability and reliability of their solder joints, 60 of the LTCC mixers were soldered onto FR-4 PCB motherboards and thermally cycled over a temperature range of –55 to 125ºC (MIL-STD-202, Method 107G, test condition B3, except –55ºC instead of –65ºC). The DC continuity was measured from the motherboard trace to the top of the LTCC board for 100 cycles, with no failures found. Mini-Circuits, P.O. Box 350166, Brooklyn, NY 112350003; (718) 934-4500, FAX: (718) 332-4661, Internet: www.minicircuits.com. REFERENCES 1. United States Patent No. 7,027,795 (2006). 2. Mini-Circuits Engineering Staff, “Double-Balanced Mixer,” Microwave Journal, October 2002, pp. 100-104. 3. “Qualification of LTCC Double Balanced Mixer,” Mini-Circuits Qualification Report D4-QR-DZ-2. VERY TINY 750MHz to15GHz MIXERS IF D C-4 GH z 4 $ from ONLY 95 OCK IN ST ea. (Qty.1000) Announcing an unprecedented series of frequency mixers that give you enormously wide RF&IF bandwidths with very high performance, super-small size, and an equally small price…available only from Mini-Circuits! They’re called SIM mixers, and they cover just about all your broadband and multi-band RF applications from 750MHz up to 15GHz with an IF from DC to 4GHz. Because of their expansive bandwidth, these double balanced mixers are also very useful for both up & down converting. The tiny Low Temperature Co-fired Ceramic (LTCC) leadless package delivers superior temperature stability, repeatable performance, high ESD capability, and meets your need for high speed automated manufacturing. And you'll find Mini-Circuits ultra-low SIM prices are as revolutionary as the mixers themselves! Mini-Circuits…we’re redefining what VALUE is all about! Model LO Power (dBm) Frequency (MHz) Conv. LO-RF LO-IF IP3 @ Price $ea. Isol. Isol. Center Band Qty. 10-49 Loss (dB) (dB) (dB) (dBm) Typ. Typ. Typ. Typ. * LO/RF fL-fU IF 2400-7000 750-4200 2300-8000 3700-10000 DC-3000 DC-1500 DC-3000 DC-4000 6.2 6.1 6.0 6.7 30 35 28 38 22 24 20 16 +10 +12 +11 +16 9.95 7.45 7.95 8.95 SIM-153+ +7 3400-15000 SIM-63LH+ +10 750-6000 SIM-83LH+ +10 1700-8000 SIM-153LH+ +10 3200-15000 Conversion Loss @ 30MHz IF. DC-4000 DC-1500 DC-3000 DC-4000 7.5 6.2 6.0 7.5 36 34 28 36 21 22 22 20 +10 +13 +11 +11 9.95 8.95 10.95 11.95 SIM-73L+ SIM-43+ SIM-83+ SIM-14+ +4 +7 +7 +7 * U.S. Patent #7,027,795 Actual Size 0.20"x 0.18" Footprint Detailed Performance Specs and Shopping Online at: www.minicircuits.com/mixer.shtml ® ISO 9001 ISO 14001 CERTIFIED P.O. Box 350166, Brooklyn, New York 11235-0003 (718) 934-4500 Fax (718) 332-4661 For quick access to product information see MINI-CIRCUITS CATALOG & WEB TM The Design Engineers Search Engine Provides ACTUAL Data Instantly From MINI-CIRCUITS At: www.minicircuits.com RF/IF MICROWAVE COMPONENTS 415 Rev Org