lt5537 Linear Technology Corporation, lt5537 Datasheet
lt5537
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lt5537 Summary of contents
Page 1
... RF/IF detector, Output Voltage, Linearity Error vs Input Power at 200MHz 2 2.0 85°C 1nF 1µF 25°C 1.6 –40°C 1.2 0.8 0.4 OUT ENBL = –80 –60 –40 –20 7 INPUT POWER (dBm) 5537 TA01a LT5537 –1 –2 – 5537 TA01b 5537fa 1 ...
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... CC EXPOSED PAD (PIN 9) SHOULD BE SOLDERED TO PCB ORDER PART NUMBER LT5537EDDB Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges. ...
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... Error R1 = 33k (Note 0V, Extrapolated OUT (Notes –20dBm Signal Present Input from –30dBm to 0dBm 2.5pF LOAD Output Load Capacitance = 2.5pF ENBL ENBL LT5537 MIN TYP MAX UNITS 90.5 dB 82.8 dB 20.3 mV/dB –95 dBm –77 dBm –0.004 dB/°C 90 ...
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... LT5537 ELECTRICAL CHARACTERISTICS PARAMETER Power Supply Supply Voltage Supply Current Shutdown Current 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. ...
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... ENBL = 85° –1 –1 –40°C –2 –2 –3 –3 –80 –60 –40 –20 INPUT POWER (dBm) LT5537 Output Voltage, Linearity Error vs Input Power at 50MHz 2 ENBL = 3V CC 2.0 85°C 25°C 1.6 1.2 –40°C 0.8 0 –80 –60 –40 –20 INPUT POWER (dBm) ...
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... LT5537 W U TYPICAL PERFOR A CE CHARACTERISTICS Output Voltage, Linearity Error vs Input Power at 400MHz 3.0 2.5 85°C 25°C 2.0 –40°C 1.5 1.0 0 ENBL = –80 –60 –40 – INPUT POWER (dBm) 5537 G13 V Variation vs Input Power OUT at 600MHz 3 NORMALIZED AT 25° ENBL = 85°C ...
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... Power Supply Pin. This pin should be decoupled CC using 1000pF and 0.1µF capacitors. V (Pin 7): Ground pin. EE OUT (Pin 8): Output pin. Exposed Pad (Pin 9): Should be connected to PCB ground. + – and CAP . – CAP CAP OFFSET CANCELLATION DETECTOR CELLS EXPOSED PAD 7 LT5537 OUT OUTPUT 8 BUFFER 7. 5537 BD 5537fa 7 ...
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... LT5537 U U APPLICATIO S I FOR ATIO The LT5537 provides a log-linear relationship between an RF/IF input voltage and its output. The input signal is amplified successively by limiting amplifier stages. A series of detector cells rectify the signals and produce an output current which is log-linearly related to the input power with a coefficient ( 3.4µ ...
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... Figure 4. Input Admittance W U Input Matching The LT5537 has a high impedance input (Figure 3). The differential input impedance is derived from S11 measure- ment with one of the input pins AC grounded (Figure 4). At 200MHz, the input is equivalent to 1.73k//1.45pF (Table 1). The input dynamic range is constant in voltage terms, ...
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... LT5537 U U APPLICATIO S I FOR ATIO The 1:4 input transformer can also be replaced with a narrow band discrete balun circuit using three compo- nents as shown in Figure 6. Capacitors C11, C12 and inductor L1 form a tank circuit having a transformer-like function over a narrow bandwidth. The increased power- to-voltage transformation and the narrower input passband serve to improve the sensitivity of the logarithmic detector ...
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... With 2.5pF loading, the output bandwidth is approximately 6MHz. The baseband response of the LT5537 was characterized with a pulsed RF input using the setup shown in Figure 8. The input to the LT5537 is a 200MHz CW RF signal switched between –30dBm and –60dBm at a rate of 600kHz. The output was connected to a FET probe (Fluke PM8943A, 10:1 tip) which has a capacitive loading of 2 ...
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... The DC cancellation also reduces the gain of the amplifier at low frequency result, the LT5537 has a bandpass frequency response with a lower end determined by the bandwidth of the offset cancellation feedback loop. ...
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... W U Offset Cancellation Loop and the Timing Response The input of the LT5537 is AC coupled, and the on-chip DC biasing is automatically regulated as described above. But if the DC component of the input signal has any transient step with sufficiently short rise or fall time (for example the ...
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... U APPLICATIO S I FOR ATIO Enable Pin Operation The enable circuit of the LT5537 is shown in a simplified form in Figure 12. When the voltage at the ENBL pin is ≥1V, the enable circuit biases the chip up for normal operation. The current drawn by the ENBL pin is dependent on the voltage on that pin ...
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... U DDB Package 8-Lead Plastic DFN (3mm × 2mm) (Reference LTC DWG # 05-08-1702) 3.00 ±0.10 (2 SIDES) PIN 1 BAR TOP MARK (SEE NOTE 6) PACKAGE OUTLINE 0.200 REF LT5537 R = 0.115 0.38 ± 0.10 TYP 0.56 ± 0. SIDES) 2.00 ±0.10 (2 SIDES 0.25 ± 0.05 0.75 ± ...
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... LT5537 RELATED PARTS PART NUMBER DESCRIPTION Infrastructure LT5511 High Linearity Upconverting Mixer LT5512 DC-3GHz High Signal Level Downconverting Mixer LT5514 Ultralow Distortion, IF Amplifier/ADC Driver with Digitally Controlled Gain LT5515 1.5GHz to 2.5GHz Direct Conversion Quadrature Demodulator LT5516 0.8GHz to 1.5GHz Direct Conversion Quadrature ...