PDF《LTC5587 6 GHz RMS Power Detector》

LTC5587

1 5587f BLOCK DIAGRAM FEATURES DESCRIPTION

6 GHz RMS Power Detector with Digital Output The LTC?

5587 is a 10MHz to 6GHz, low power monolithic precision RMS power detector with an integrated 12-bit serial analog-to-digital converter (ADC).

The RMS detec- tor uses a proprietary technique to accurately measure the RF power of modulated signals with crest-factor as high as 12dB. For an input frequency of 2.14GHz the detection range is from C34dBm to 6dBm. The serial digital output 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 resistor to the analog output pin (VOUT). This enables further filtering of the output modu- lation ripple using an off-chip capacitor before analog-to- digitalconversion. TheADCfeaturesincludenodatalatency, no missing codes, and a sampling rate of up to 500ksps. A dedicated external reference pin (VREF) can be tied to VDD orothersuitablelow-impedancevoltagereferencetosetthe ADC full-scale input voltage range. The ADC also features an automatic power down after each conversion making the LTC5587 ideal for low-power applications. APPLICATIONS n Frequency Range: 10MHz to 6GHz n Accurate Power Measurement of High Crest Factor (Up to 12dB) Waveforms n 40dB Log Linear Dynamic Range n Exceptional Accuracy Over Temperature n Single-Ended RF Input n 0.014dB/Bit (12-Bit) ADC Resolution (VREF = 1.8V) n ADC Sample Rate Up to 500ksps n SPI/MICROWIRE Serial I/O n Compatible with 1V to 3.6V Digital Logic n Fast Response Time: 1μs Rise, 8μs Fall n Low Power: 3mA at 3.3V and 500ksps n Small 3mm * 3mm 12-pin DFN Package n LTE, WiMAX, W-CDMA, TD-SCDMA, CDMA, CDMA2000, EDGE, GSM n Pico-Cells, Femto-Cells RF Power Control n Wireless Repeaters n CATV/DVB Transmitters n MIMO Wireless Access Points n Portable RMS Power Measurement n Antenna Monitor L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

5587 BD EXPOSED PAD VOUT SDO VDD VREF GND VCC EN CSQ OVDD RF

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13 150kHz LPF OUTPUT BUFFER 300Ω RMS DETECTOR THREE-STATE SERIAL OUTPUT PORT S/H 12-BIT ADC

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1 SCK

2 CONV

12 TIMING LOGIC BIAS

5 Linearity Error vs RF Input Power 2140MHz Modulated Waveforms

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0 C2 C1 C3

3 RF INPUT POWER (dBm) LINEARITY ERROR (dB) C30 C20 C10 C35 C25

0 10 C15 C5

5 5587 G12 TA = 25°C CW WCDMA, UL WCDMA DL 1C WCDMA DL 4C LTE DL 1C LTE DL 4C LTC5587

2 5587f PIN CONFIGURATION ABSOLUTE MAXIMUM RATINGS (Note 1) TOP VIEW DFN PACKAGE 12-LEAD (3mm * 3mm) PLASTIC DFN

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2 1 CONV VDD VREF EN VCC RF SDO SCK OVDD VOUT GND CSQ

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13 GND TJMAX = 150°C, θJA = 76°C/W EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC5587IDD#PBF LTC5587IDD#TRPBF LFRH 12-Lead (3mm * 3mm) Plastic DFN C40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ VDD, VCC Voltage, (Note 12)4V OVDD Supply Voltage Min(VDD + 0.3V, 4V) Maximum Input Signal Power (Average)15dBm Maximum Input Signal Power (Peak)25dBm DC Voltage at RF.0.3V to 2V VOUT Voltage.0.3V to VDD + 0.3V EN Voltage 0.3V to VDD + 0.3V SDO, SCK, CONV Voltage.0.3V to VDD + 0.3V VREF Voltage.0.3V to VDD + 0.3V Power Dissipation.100mW Maximum Junction Temperature, TJMAX 150°C Operating Temperature Range (Note 2)....C40°C to 85°C Storage Temperature Range.65°C to 150°C Caution:Thispartissensitivetoelectrostaticdischarge.It isveryimportantthatproperESDprecautionsbeobserved when handling the LTC5587. PARAMETER CONDITIONS MIN TYP MAX UNITS RF Input Input Frequency Range (Note 4)