DEMO CIRCUIT 1599A QUICK START LTC5583 GUIDE LTC5583. DUAL 6GHz RMS POWER DETECTOR DESCRIPTION

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1 DEMO CIRCUIT 599A QUICK START LTC558 GUIDE LTC558 DUAL 6GHz RMS POWER DETECTOR DESCRIPTION Demonstration circuit 599A is a Mean-Squared Power Detector featuring the LTC 558 IC. LTC558 is a dual-channel RMS power detector, capable of measuring two AC signals. It provides 40dB of channel to channel isolation with no frequency separation at 40MHz that is suited for measuring VSWR. The LTC558 is a wide dynamic range Mean Squared RF Power Detector, operational from 40MHz to 6GHz. The input dynamic range with ±db nonlinearity is 60dB depending on frequency(from 58dBm to +dbm, single-ended 50 input). The detector output voltage slope is normally 0mV/dB, and the typical output variation over temperature is ±0.5dB at 880MHz. The DC599A Demo Circuit is ideal for frequency operation below.0ghz. It has the single ended input drive to LTC558. The input A to output B (or input B to output A) isolation is db at.7ghz, and degrades as input frequency increases. As a result, operating above GHz may require differential input matching for improved isolation. Temperature performance is optimized for 40MHz. Contact LTC applications for more information. LTC is a trademark of Linear Technology Corporation Design files for this circuit board are available. Call the LTC factory. Typical Performance Summary (V CC =.V, EN = HIGH, T A = 5 C, unless otherwise noted. Test circuit shown in Figure.) PARAMETER CONDITION VALUE Supply Voltage.V to.5v Supply Current Envelope detector off 80.5mA Envelope detector on 90.mA Shutdown Current EN = Lo 0.μA EN Voltage EN Input Current Low, Chip Disabled HIGH, Chip Enabled V EN = 0V V EN =.V 0.V max V min 0μA 00μA Output Start Voltage No Input Signal Present 0.45V Rise Time 0.5V to.v, 0% to 90%, C FLTRA =C FLTRB = 8.nF, F RF = 00 MHz 40nS Fall Time.V to 0.5V, 90% to 0%, C FLTRA =C FLTRB =8.nF, F RF = 00 MHz.5uS Input Frequency Range Operation over wider frequency range with reduced performance 40MHz to 6GHz f =450MHz Linear Dynamic Range ± db linearity error 6 db RF Input Power Range CW, 50Ω, ±db Linearity Error -59 to 4 dbm Slope 9.6mV/dB Logarithmic Intercept -78.5dBm

2 LTC558 Deviation from CW Response db peak-to-average ratio (4 carrier WCDMA) 0.4 INA to VOB isolation P INB = -45dBm, VOB= VOB p INB ± db, Frequency Separation=0Hz 50dB INB to VOA isolation P INA = -45dBm, VOA= VOA p INA ± db, Frequency Separation=0Hz 50dB f =40MHz Linear Dynamic Range ± db linearity error 60 db RF Input Power Range CW, 50Ω, ±db Linearity Error -58 to dbm Slope 9.6mV/dB Logarithmic Intercept -77.4dBm Deviation from CW Response db peak-to-average ratio (4 carrier WCDMA) 0. INA to VOB isolation P INB = -45dBm, VOB= VOB p INB ± db, Frequency Separation=0Hz 40dB INB to VOA isolation P INA = -45dBm, VOA= VOA p INA ± db, Frequency Separation=0Hz 40dB f =700MHz Linear Dynamic Range ± db linearity error 59 db RF Input Power Range CW, 50Ω, ±db Linearity Error -56 to dbm Slope 0mV/dB Logarithmic Intercept -74.9dBm Deviation from CW Response db peak-to-average ratio (WiMAX OFDM) 0.6dB INA to VOB isolation P INB = -45dBm, VOB= VOB p INB ± db, Frequency Separation=0Hz db INB to VOA isolation P INA = -45dBm, VOA= VOA p INA ± db, Frequency Separation=0Hz db Table. Jumper Description JUMPER FUNCTION RANGE/SETTING (DEFAULT) JP Chip Enable. EN for High, DIS for Lo EN JP N. Power supply to the envelop detector for both channels. HI=on, LO=off LO JP INV. Swap control for the polarity of VODF. HI=(VOB-VOA)+VOS, LO=(VOA-VOB)+VOS LO QUICK START PROCEDURE Demonstration circuit 599A is easy to set up to evaluate the performance of the LTC558. Refer to Figure for measurement equipment setup and follow the procedure below:. Connect voltmeter s negative (-) lead to demo board GND test point(tp8 or TP9).. Connect voltmeter s positive (+) lead to the demo board VOA(TP) and VOB(TP5) to measure channel A and channel B output respectively.. Connect DC power supply s negative (-) output to demo board GND(TP8 or TP9). 4. Connect DC power supply s positive (+) output (.V to.5v) to demo board V CC test point(tp7). Do not exceed.8v, the absolute maximum supply voltage. Set N jumper to LO, to turn off the envelope detector if not needed. Set the Swap jumper to LO for: VODF= (VOA-VOB)+VOS. Set swap to HI for: VODF=(VOB-VOA)+VOS 5. Connect signal generator s output to demo board INPUT port (SMA connector J for channel A input, or J for channel B input) via coaxial cable.

3 LTC A db attenuator may be inserted for broadband input match, the detected power range is shifted higher by db. 7. Set the JP to EN to enable the IC. Now the detector is enabled (on) and is ready for measurement. 8. Apply RF input signal and measure OUTPUT DC voltages at VOA and VOB. Do not exceed +8dBm, the absolute maximum RF input power. NOTES:. The voltage on the EN test point must never exceed + 0.V.. For digitally modulated signals, an oscilloscope can be used to observe the AC components of the output.. Suggest to set N LO when envelope detector is not used. This will result in lower power consumption. 4. Temperature compensation values for RT and RT may be different at different frequencies. See table for additional information. Figure. Proper Test Equipment Setup

4 LTC558 Frequency (MHz) RP RP RT RT 450 Open Open Open Open Open Open Open Open Table. Suggested RT and RT values for the optimum temperature performance at various RF input frequencies. 4

5 LTC558 TP8 GND C4 0.pF JP EN DIS C7 uf C8 0nF C5 C 00pF R 0 C6 C0 C C 00nF R9 0 C8 C4 C9 TP6 ENVB INA J C9 0.pF DECA A R EN B DECB VOA 8 RT VODF RT 7 6 VOS 5 4 VOB INPB U LTC558IUF INNB RP FLTRB ENVB INV INPA INNA RP FLTRA ENVA 4 0 N 9 TP7 GND TP9 R 060 C L 0 L 0 C C7 C C6 C9 0pF C8 0pF C C 0pF R8 OPT C 00nF R OPT C5 OPT R JP N HI LO R4 OPT R0 75 C5 C0 00pF R OPT C OPT R C6 0pF 0 NOTE: UNLESS OTHERWISE SPECIFIED,. ALL CAPACITORS AND RESISTORS ARE 040. TP ENVA INB J 75 C7 JP INV R6.0k % R7 OPT.V -.5V C4 C R5 9.76k % HI C0 LO TP TP TP4 TP5 VOA VODF VOS VOB 5

6 LTC558 Bill of Materials: 6