lt5581 Linear Technology Corporation, lt5581 Datasheet
lt5581
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lt5581 Summary of contents
Page 1
... It outputs a DC voltage in linear scale proportional input signal power in dBm. The LT5581 is suitable for precision power measurement and control for a wide variety of RF standards, including GSM/EDGE, CDMA, CDMA2000, W-CDMA, TD- SCDMA, UMTS, LTE and WiMAX, etc. The fi ...
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... Operating Temperature Range.................. –40°C to 85°C Storage Temperature Range ................... –65°C to 150°C CAUTION: This part is sensitive to electrostatic discharge very important that proper ESD precautions be observed when handling the LT5581. ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT5581IDDB#PBF LT5581IDDB#TRPBF Consult LTC Marketing for parts specifi ...
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... Normalized to Output at 25°C, –40°C < –27 to –10dBm IN WiMAX OFDMA Preamble WiMAX OFDM Burst Externally Matched to 50Ω Source ±1dB Linearity Error Normalized to Output at 25°C, –40°C < –30 to +6dBm IN LT5581 MIN TYP MAX –57 –52 – –42 < 85°C; ...
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... Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LT5581 is guaranteed to meet specifi ed performance from –40°C to 85°C. Note 3: The linearity error is calculated by the difference between the incremental slope of the output and the average output slope from – ...
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... RF INPUT POWER (dBm) LT5581 Performance characteristics taken at V Linearity Error vs Frequency 10MHz 450MHz –1 880MHz 2.14GHz –2 2.6GHz 3.5GHz 5.8GHz – – ...
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... LT5581 TYPICAL PERFORMANCE CHARACTERISTICS Output Voltage and Linearity Error at 2140MHz 2.0 25°C 1.8 85°C – 40°C 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 –40 –30 –25 –20 –15 – –35 – INPUT POWER (dBm) 5581 G10 Output Voltage and Linearity Error at 2600MHz 2.0 25°C 1.8 85°C – 40°C 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 –40 –35 – ...
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... 85° SLOPE (mV/dB 5581 G25 LT5581 Linearity Error vs RF Input Power, 5.8GHz Modulated Waveforms 85°C 0 –40°C –1 –2 CW WiMax OFDM BURST – –30 –25 –20 –15 –10 0 – ...
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... LT5581 TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs RF Input Power 25° –25 –20 –15 –10 RF INPUT POWER (dBm) Return Loss vs Frequency Reference in Figure 1 Test Circuit 25°C A –5 –10 –15 –20 –25 – FREQUENCY (GHz) L1 2.2nH, 1.5pF L1 1nH, 1 ...
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... PCB ground, using many through-hole vias. See the layout information in the Ap- plications Information section. 9 EXPOSED PAD OUTPUT BUFFER 150kHz LPF RMS DETECTOR BIAS LT5581 300Ω V OUT 3 GND 5 6 5581 BD 5581f 9 ...
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... AVX 06033C102KAT2A R2 68Ω 0603 10 C7 0.1μ 100pF C3 0.01μ LT5581 R3 0Ω GND NC V OUT C4 OPT GND GND GND NC 9 PINS OPTIONAL GROUND PART NUMBER FREQUENCY 1GHz to 2.2GHz 2GHz to 2.6GHz 2.6GHz to 3.4GHz 3 ...
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... APPLICATIONS INFORMATION OPERATION To achieve an accurate average power measurement of the high crest factor modulated RF signals, the LT5581 combines a proprietary high speed power measurement subsystem with an internal 150kHz low pass averag- ing fi lter and an output voltage buffer in a completely integrated solution with minimal off-chip components. ...
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... C2, is conservatively set at 1000pF. Output Interface The output buffer of the LT5581 is shown in Figure 6. It includes a push-pull stage with a series 300Ω resistor. The output stage is capable of sourcing and sinking 5mA of current. The output pin can be shorted to GND or V without damage, but going beyond V – ...
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... C LOAD 0.2 Figure 7. Residual Ripple, Output Transient Response for RF Pulse with WCDMA 4-Carrier Modulation NO CAP 0.047μF 2 1.6 1.8 5581 F08 Figure 9. Residual Ripple, Output Transient Times for RF Pulse with WCDMA 4-Carrier Modulation vs External Filter Capacitor C4 LT5581 1. 25° CAP 1.20 0.01μF 1.15 1.10 1.05 1 ...
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... LT5581 APPLICATIONS INFORMATION Figure 10 shows that rise time and fall time are strong functions of RF input power. Data is taken without the output fi lter capacitor. For a given RF modulation type—WCDMA, for exam- ple—the internal 150kHz fi lter provides nominal fi ltering of the residual ripple level. Additional external fi ...
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... Enable Pin A simplifi ed schematic of the EN pin is shown in Figure 14. To enable the LT5581 necessary to put greater than 1V on this pin. To disable or turn off the chip, this voltage should be below 0.3V enable voltage of 3.3V, the pin draws roughly 20μA. If the EN pin is not connected, the chip is disabled through an internal 500k pull-down resistor ...
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... LT5581 RELATED PARTS PART NUMBER DESCRIPTION RF Power Detectors LTC ® 5505 RF Power Detectors with >40dB Dynamic Range 300MHz to 3GHz, Temperature Compensated, 2. Supply LTC5507 100kHz to 1000MHz RF Power Detector LTC5508 300MHz to 7GHz RF Power Detector LTC5509 300MHz to 3GHz RF Power Detector LTC5530 300MHz to 7GHz Precision RF Power Detector ...