lt5568 Linear Technology Corporation, lt5568 Datasheet
lt5568
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lt5568 Summary of contents
Page 1
... All other trademarks are the property of their respective owners 100nF LT5568 850MHz TO 965MHz PA 0° 90° BALUN 55682 TA01 VCO/SYNTHESIZER LT5568-2 High Linearity Direct U GSM EVM and Noise vs RF Output Power at 900MHz 5 –96 4 –98 3 –100 NOISE 2 –102 EVM –104 ...
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... Storage Temperature Range ................... –65°C to 125°C Voltage on Any Pin Not to Exceed ...................... –500mV to V CAUTION: This part is sensitive to ESD very important that proper ESD precautions be observed when handling the LT5568-2. ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT5568-2EUF#PBF LT5568-2EUF#TRPBF Consult LTC Marketing for parts specifi ...
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... LO feedthrough nulling (unadjusted). Note 17: The difference in conversion gain between the spurious signal • LO – BB versus the conversion gain at the desired signal for BB = 2MHz and LO = 900MHz. Note 18: The input voltage corresponding to the output P1dB. LT5568-2 = 25° 900MHz 902MHz ...
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... LT5568 TYPICAL PERFOR A CE CHARACTERISTICS P = 0dBm. BBPI, BBMI, BBPQ, BBMQ inputs 0.54V LO sideband selection –10dBm (–10dBm/tone for 2-tone measurements), unless otherwise noted. (Note 3) RF, OUT Supply Current vs Supply Voltage 120 85°C 25°C 110 –40°C 100 90 4.5 5 SUPPLY VOLTAGE (V) 55682 G01 ...
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... OR f – 2 • HD3 = MAX POWER • – 3 • 55682 G17 LT5568 High 25° 900MHz 2MHz, I&Q 90° shifted and RF Port Return Loss vs RF Frequency 0 LO PORT LOW LO PORT HIGH, – ...
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... LT5568 TYPICAL PERFOR A CE CHARACTERISTICS P = 0dBm. BBPI, BBMI, BBPQ, BBMQ inputs 0.54V LO sideband selection –10dBm (–10dBm/tone for 2-tone measurements), unless otherwise noted. (Note 3) RF, OUT LO Feedthrough to RF Output vs CW Baseband Voltage –36 5V, –40°C 5V, 25°C 5V, 85°C 4.5V, 25°C –38 5.5V, 25° ...
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... ESD protection diodes. BBPI, BBMI (Pins 14, 16): Baseband Inputs for the I-channel, each with 50Ω input impedance. Internally biased at about 0.54V. Applied voltage must stay below 2.5V. Exposed Pad (Pin 17): Ground. This pin must be soldered to the printed circuit board ground plane. LT5568-2 + 0.5V in order CC 55682f 7 ...
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... LT5568-2 W BLOCK DIAGRA BBPI BBMI BBPQ BBMQ U U APPLICATIO S I FOR ATIO The LT5568-2 consists of I and Q input differential volt- age-to-current converters, I and Q up-conversion mixers output balun quadrature phase generator and LO buffers BALUN CC LOMI R1A R1B 25Ω ...
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... V = –2V to –5.25V SS Figure 3. LT5568-2 GSM Baseband Interface with 3rd Order Lowpass Filter and Ground Referenced DAC (Only I-Channel is Shown The baseband inputs should be driven differentially; other- wise, the even-order distortion products will degrade the overall linearity severely. Typically, a DAC will be the signal source for the LT5568-2. Reconstruction fi ...
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... LT5568 APPLICATIO S I FOR ATIO LO Section The internal LO input amplifi er performs single-ended to differential conversion of the LO input signal. Figure 4 shows the equivalent circuit schematic of the LO input 20pF LO INPUT 5568 F04 Figure 4. Equivalent Circuit Schematic of the LO Input The internal, differential LO signal is then split into in-phase and quadrature (90° ...
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... Enable Interface –126.9 Figure 6 shows a simplifi ed schematic of the EN pin –133.9 interface. The voltage necessary to turn on the LT5568-2 –143.1 is 1V. To disable (shut down) the chip, the enable voltage –151.6 must be below 0.5V. If the EN pin is not connected, the chip is disabled. This EN = Low condition is assured by the 75k on-chip pull-down resistor ...
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... J1 BBMI BBMI GND BBPI V CC 100Ω GND GND LT5568-2 LO GND IN 4 GND GND GND BBMQ GND BBPQ BBMQ GND BOARD NUMBER: DC1178A Figure 7. Evaluation Circuit Schematic (optional) limits the EN pin current in the event that ...
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... RF FREQUENCY (MHz) Figure 12. 1-Carrier CDMA2000 Spectrum W U Because of the LT5568-2’s very high dynamic range, the test equipment can limit the accuracy of the ACPR mea- surement. See Application Note 99. Consult the factory for advice on the ACPR measurement, if needed. The ACPR performance is sensitive to the amplitude match of the BBPI and BBMI (or BBPQ and BBMQ) inputs ...
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... U APPLICATIO S I FOR ATIO the same (but of opposite sign). The current will enter the LT5568-2’s common-base stage, and will fl the mixer upper switches. This can be seen in Figure 1 where the internal circuit of the LT5568-2 is drawn. After calibration when the temperature changes, the LO feedthrough and the image rejection performance will – ...
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... UF Package 16-Lead Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1692) 0.72 ±0.05 PACKAGE OUTLINE 0.30 ±0.05 0.65 BSC 0.75 ± 0.05 2.15 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LT5568-2 BOTTOM VIEW—EXPOSED PAD PIN 1 NOTCH R = 0.20 TYP OR 0.35 × 45° CHAMFER R = 0.115 TYP 15 16 0.55 ± 0. (UF16) QFN 10-04 0.30 ± 0.05 ...
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... Very High Linearity Downconverting Mixer LT5558 600MHz to 1100MHz High Linearity Direct Quadrature Modulator LT5560 Ultra-Low Power Active Mixer LT5568 700MHz to 1050MHz High Linearity Direct Quadrature Modulator LT5572 1.5GHz to 2.5GHz High Linearity Direct Quadrature Modulator LT5575 800MHz to 2.7GHz High Linearity Direct ...