lt5579 Linear Technology Corporation, lt5579 Datasheet
lt5579
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lt5579 Summary of contents
Page 1
... The LT5579 offers a high performance alternative to pas- sive mixers. Unlike passive mixers, which have conversion loss and require high LO drive levels, the LT5579 delivers conversion gain at signifi cantly lower LO input levels and is less sensitive to LO power level variations. The lower ...
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... ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT5579IUH#PBF LT5579IUH#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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... 456MHz 3600MHz IF RF Note 3: The LT5579 is guaranteed to meet specifi ed performance from –40°C to 85°C Note 4: SSB noise fi gure measurements performed with a small-signal noise source and bandpass fi lter on LO signal generator. No other IF signal applied. LT5579 = –5dBm (–5dBm/tone for 2-tone tests, ...
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... LT5579 TYPICAL DC PERFORMANCE CHARACTERISTICS TYPICAL AC PERFORMANCE CHARACTERISTICS V = 3.3V 25° 456MHz output measured at 3600MHz, unless otherwise noted. (Test circuit shown in Figure 1) Gain Distribution at 3600MHz 90° 25° –45° –2.5 –2.0 –1.5 –1.0 –0.5 0 0.5 1.0 GAIN (dB) ...
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... RF Output Power (2-Tone) 0 –20 –40 –60 –80 –100 6 –12 –10 –8 –6 –4 – OUTPUT POWER (dBm/TONE) LT5579 3300MHz to 3800MHz Application: = –1dBm, LO LO-RF Leakage vs RF Output Frequency 0 –10 –20 –30 –40 85°C 25°C –40°C –50 3200 3300 3400 3500 ...
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... LT5579 TYPICAL AC PERFORMANCE CHARACTERISTICS V = 3.3V 25° 456MHz output measured at 2600MHz, unless otherwise noted. (Test circuit shown in Figure 1) Conversion Gain and OIP3 vs RF Output Frequency 16 12 OIP3 8 85°C 25°C GAIN –40° –4 2200 2400 2500 2600 2700 2800 ...
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... LO INPUT POWER (dBm) IM2 Level vs RF Output Power (2-Tone) 0 –20 –40 –60 –80 –100 6 –10 –8 –6 –4 – OUTPUT POWER (dBm/TONE) LT5579 2140MHz Application: = –1dBm, LO LO-RF Leakage vs RF Output Frequency 0 –10 –20 –30 –40 85°C 25°C –40°C –50 2350 1950 2050 ...
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... LT5579 TYPICAL PERFORMANCE CHARACTERISTICS V = 3.3V 25° 240MHz output measured at 1750MHz, unless otherwise noted. (Test circuit shown in Figure 1) Conversion Gain and OIP3 vs RF Output Frequency 16 OIP3 12 85°C 8 25°C –40°C GAIN 4 0 –4 1650 1700 1750 1800 1850 ...
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... DC block to this pin. Exposed Pad (Pin 25): PGND. Electrical and thermal ground connection for the entire IC. This pad must be soldered to a low impedance RF ground on the printed circuit board. This ground must also provide a path for thermal dissipation. LT5579 5579f 9 ...
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... LT5579 BLOCK DIAGRAM LO 22 GND PINS ARE NOT SHOWN EXPOSED RF PAD DOUBLE LO BUFFER BALANCED V CC2 V CM CTRL + – MIXER V CC2 BIAS 8 5579 BD 5579f ...
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... Figure 1. Test Circuit Schematic LT5579 18 GND 17 GND RF 16 OUTPUT GND L3 TL3 GND 13 GND 5579 F01 SIZE ...
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... Internal baluns are used to provide single-ended LO input and RF output ports. The IF input is differential. The LT5579 is intended for opera- tion in the 1.5GHz to 3.8GHz frequency range, though operation outside this range is possible with reduced performance ...
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... FREQUENCY (MHz) 5579 F03 Figure 3. IF Input Return Loss with 70MHz (a), 240MHz (b) and 456MHz (c) Matching LT5579 C9 C3 L1, L2 R1, R2 MATCH BW (pF) (pF) (nH) (Ω) (at 12dB RL) 120 (1) 100 9.1 <50 to 158 33 (1) ...
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... LT5579 APPLICATIONS INFORMATION LO Input Interface The simplifi ed schematic for the single-ended LO input port is shown in Figure 4. An internal transformer provides a broadband impedance match and performs single-ended to differential conversion. An internal capacitor also aids in impedance matching and provides DC isolation to the primary transformer winding. The transformer secondary feeds the differential limiting amplifi ...
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... The component values and approximate matching band- widths are listed in Table 5. DC and RF Grounding The LT5579 relies on the back side ground for both RF and thermal performance. The Exposed Pad must be soldered to the low impedance topside ground plane of the board. Several vias should connect the topside ground to other ground layers to aid in thermal dissipation ...
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... These circuits were evaluated using the circuit board shown in Figure 12. 1650MHz Application In this case, the LT5579 was evaluated while tuned for 70MHz and an RF output of 1650MHz. The matching confi guration is shown in Figure 8. Input capacitors are used only as DC blocks in this ap- plication ...
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... LO drive. With this matching confi guration, the low side LO case outperforms the high side LO. The gain, noise fi gure (SSB) and OIP3 are plotted as a function of RF output frequency. LOW SIDE LO HIGH SIDE LO 1700 1750 5579 F09 LT5579 35 OIP3 25° ...
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... LT5579 TYPICAL APPLICATIONS 2140MHz with Low Side LO The LT5579 was fully characterized with an RF output of 2140MHz and a high side LO. The part also works well when driven with low side LO, however, the performance benefi ted from the addition of common mode capacitance to the IF input match ...
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... UH Package 24-Lead Plastic QFN (5mm × 5mm) (Reference LTC DWG # 05-08-1747 Rev Ø) 0.75 ±0.05 PACKAGE OUTLINE 0.30 ± 0.05 0.65 BSC R = 0.05 TYP 0.75 ± 0.05 0.00 – 0.05 3.25 REF 0.200 REF LT5579 PIN 1 NOTCH R = 0.30 TYP BOTTOM VIEW—EXPOSED PAD OR 0.35 45° CHAMFER R = 0.115 TYP 23 24 0.55 ± 0. 3.20 ± 0.10 3.20 ± ...
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... LT5579 RELATED PARTS PART NUMBER DESCRIPTION Infrastructure LT5514 Ultralow Distortion, IF Amplifi er/ADC Driver with Digitally Controlled Gain LT5517 40MHz to 900MHz Quadrature Demodulator LT5518 1.5GHz to 2.4GHz High Linearity Direct Quadrature Modulator LT5519 0.7GHz to 1.4GHz High Linearity Upconverting Mixer LT5520 1.3GHz to 2.3GHz High Linearity Upconverting ...