ltc5587 Linear Technology Corporation, ltc5587 Datasheet
ltc5587
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ltc5587 Summary of contents
Page 1
... REF of the detector is a 12-bit word value that is directly pro- portional to the RF signal power measured in dBm. The LTC5587 is suitable for precision power measurement for a wide variety of RF standards, including LTE, WiMAX, W-CDMA, TD-SCDMA, CDMA, CDMA2000, EDGE, GSM, etc. The DC output of the detector is connected in series with an on-chip 300Ω ...
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... Operating Temperature Range (Note 2)....–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 LTC5587. ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL ...
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... CW Input: Externally Matched to 50Ω Source ±1dB Linearity Error Normalized to Output at 25° –34dBm to 6dBm IN Normalized to Output at 25° –27dBm to –10dBm IN WiMax OFDMA Preamble WiMax OFDM Burst CW Input: Externally Matched to 50Ω Source ±1dB Linearity Error LTC5587 = OV = 3.3V 1.8V 3.3V REF SMPL MIN TYP MAX ±0.5 ±0.1 ± ...
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... LTC5587 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are and unless otherwise noted. Test circuit is shown in Figure 1. SMPL(MAX) SCK SCK(MAX) PARAMETER Output Variation vs Temperature Output Variation vs Temperature Deviation from CW Response –34dBm to –4dBm IN Detector Analog Output Output DC Voltage at V OUT Output Impedance ...
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... The maximum RF input power rating is guaranteed by design and engineering characterization, but not production tested. Note 2: The LTC5587 is guaranteed to be functional over the operating temperature range 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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... LTC5587 TYPICAL PERFORMANCE CHARACTERISTICS and unless otherwise noted. V SMPL SMPL(MAX) SCK SCK(MAX) Output Voltage vs Frequency 2 25°C A 1.8 10MHz 1.6 450MHz 880MHz 1.4 2.14GHz 1.2 2.6GHz 3.5GHz 1.0 5.8GHz 0.8 0.6 0.4 0.2 0 –40 –35 –30 –25 –20 –15 –10 – INPUT POWER (dBm) 5587 G01 Output Voltage and Linearity Error at 450MHz 2 ...
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... RF INPUT POWER (dBm) LTC5587 3.3V 1.8V 3.3V REF Linearity Error vs RF Input Power 2140MHz Modulated Waveforms 25° 85° –40°C CW – ...
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... LTC5587 TYPICAL PERFORMANCE CHARACTERISTICS and unless otherwise noted. V SMPL SMPL(MAX) SCK SCK(MAX) Output Voltage and Linearity Error at 5800MHz 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 –30 –25 –20 –15 –10 – INPUT POWER (dBm) 5587 G19 Slope vs Frequency ...
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... Output Transient Response with RF Pulse and EN Pulse 5000 5 RFAND 25°C PULSE A 0 4000 –5 3000 2000 –10 1000 –15 – 100 5587 G32 LTC5587 3.3V 1.8V 3.3V REF 25° PULSE ON OFF 10dBm IN – 0dBm – ...
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... LTC5587 PIN FUNCTIONS SDO (Pin 1): Three-State Serial Data Output. The A/D conversion result is shifted out on SDO as a serial data stream with MSB first. The data stream consists of 12 bits of conversion data followed by trailing zeros. SCK (Pin 2): Shift Clock Input. The SCK serial clock syn- chronizes the serial data transfer ...
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... SDO Into Hi-Z State After CONV Rising Edge t 8 CONV 1.6V Hi-Z SDO 5587 TD01 SDO Data Valid Hold Time After SCK Falling Edge t 7 SCK 1. SDO V IL SDO Data Valid Access Time After SCK Falling Edge t 4 SCK 1.6V SDO LTC5587 5587 TD02 5587 TD03 5587f 11 ...
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... AVX 04023C103KAT2A C2, C4 1000pF 0402 AVX 04025C102KAT2A R1 68Ω 0402 REF SDO CONV 1μ SLK V DD LTC5587 REF OUT C6 1μ GND GND 1000pF 0.01μF ...
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... APPLICATIONS INFORMATION Operation The LTC5587 combines a proprietary high-speed power detector with an internal 150kHz lowpass averaging filter and a true 12-bit successive approximation ADC with a serial output interface. It can accurately measure the RMS power of high crest-factor modulated RF signals. The output voltage of the RF power detector is converted to a 12-bit digital word that is directly proportional to the average RF input power in dBm ...
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... C 900MHz sampling accuracy. For example, when the sample rate of the ADC is changed from 25ksps to 500ksps, the output 5587 F04 value changes less than 0.2dB with any choice of C pin of the LTC5587 is shown in OUT OUT (or V whichever is lower) without ...
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... Figure 9 shows the rise time and fall time is a strong function of the RF input power when the filter capacitor is not present. NO CAP 0.047μF Figure 9. RF Pulse Response Rise Time and Fall Time vs RF Input Power 1.6 1.8 2 5587 F07 LTC5587 9 1000 RIPPLE T = 25°C A RISE 8 FALL ...
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... LTC5587 APPLICATIONS INFORMATION For a given RF modulation type, WCDMA for example, the internal 150kHz filter provides nominal filtering of the residual ripple level. Additional external filtering happens in the log-domain, which introduces a systematic log-er- ror in relation to the signal’s crest factor as shown in the 1 following equation – ...
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... SCK will produce the 12-bit data and four 0.45 trailing zeros on SDO. 0.375 Sleep Mode 0.3 The LTC5587 ADC enters sleep mode to save power after 0.225 each conversion if CONV remains high. In sleep mode, all 0.15 bias currents are shut down and only leakage currents 0.075 remain (about 0.1μ ...
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... INPUT VOLTAGE (V) Figure 15. ADC Transfer Characteristics 18 Detector Enable Pin A simplified schematic of the EN pin is shown in Figure 16. down to 1.4V enable the LTC5587 detector it is necessary to put DD pin greater than 2V on this pin. To disable or turn off the OUT detector, this voltage should be below 0.3V enable voltage of 3.3V the pin draws roughly 20μ ...
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... Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1725 Rev A) 0.70 ±0.05 2.38 ±0.05 PACKAGE OUTLINE 0.45 BSC 2.25 REF R = 0.115 TYP 7 3.00 ±0.10 1.65 ± 0.10 (4 SIDES) 6 0.75 ±0.05 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD LTC5587 0.40 ± 0.10 12 2.38 ±0.10 PIN 1 NOTCH R = 0.20 OR 0.25 × 45° CHAMFER 1 0.23 ± 0.05 0.45 BSC 2.25 REF (DD12) DFN 0106 REV A 5587f 19 ...
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... Quadrature Modulator Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 10MHz to 6GHz Infrastructure Power Amplifier Level Control 1 12 SDO CONV 2 11 SCK V DD LTC5587 1μ REF OUT 1000pF 5 8 GND V CC 0.01μ ...