LTC5583 Matched Dual-Channel 6GHz RMS Power Detector FEATURES DESCRIPTION n The LTC®5583 is a dual-channel RMS power detector, capable of measuring two AC signals with wide dynamic range, from –59dBm to 4dBm, depending on frequency. Each AC signal’s power in decibel-scaled value is precisely converted to a DC voltage on a linear scale, independent of the crest factor of the input signal waveforms. The LTC5583 is suitable for precision power measurement and level control for a variety of RF standards, including LTE, EDGE, W-CDMA, CDMA2000, TD-SCDMA, and WiMAX. n n n n n n n n n n Frequency Range: 40MHz to 6GHz Linear Dynamic Range: Up to 60dB ±0.5dB (Typ) Accuracy Over Temperature 40dB Channel-to-Channel Isolation at 2GHz Even with Single-Ended RF Inputs Matched Dual-Channel Outputs: <1.25dB (Typ) Single-Ended RF Inputs—No Transformer Required Accurate RMS Power Measurement of High Crest Factor Modulated Waveforms Difference Output Provides VSWR Measurement Fast Envelope Detector Outputs Fast Response Time: 140ns Rise Time Small 4mm × 4mm QFN24 Package Good channel-to-channel isolation is necessary for operating the dual channels simultaneously. For applications where the two input signals are at the same frequency (e.g. measuring VSWR), the LTC5583 provides 40dB isolation at 2.14GHz even with single-ended inputs. No baluns are needed. When the two input signals are at different frequencies, the isolation can be as high as 50dB. The isolation can be improved to >55dB with differential inputs. APPLICATIONS n n n n n VSWR Monitor MIMO Transmit Power Control Basestation PA Control Transmit and Receive Gain Control RF Instrumentation The power difference of the two input signals is provided at a difference output pin. Each channel also has a fast envelope detector, which tracks the RF input signal’s envelope and outputs a voltage directly proportional to the signal’s instantaneous power. The envelope detectors can be disabled to reduce power consumption. 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. Protected by U.S. Patents including 7262661, 7317357, 7622981. TYPICAL APPLICATION Output Voltage and Linearity Error vs RF Input Power, 2140MHz CW Inputs, Single-Ended Drive Block Diagram IN+A 2.5 IN–A ENVA 2.0 2.0 1.5 RMS DETECT + VODF – ENVB ENVELOPE DETECT DIFFERENCE AMPLIFIER RMS DETECT IN+B IN–B INV VOB VOA, VOB (V) 1.0 1.5 0.5 1.0 –0.5 0 0.5 0 –65 VOS 5583 BD 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –1.0 LINEARITY ERROR (dB) ENVELOPE DETECT LTC5583 2.5 VOA –1.5 –2.0 –2.5 5 5583 TA01b 5583fa 1 LTC5583 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Note 1) VCCN ENVA FLTA RP1 IN+A IN–A TOP VIEW Supply Voltage .........................................................3.8V Enable Voltage .................................–0.3V to VCC + 0.3V VOS Voltage ......................................–0.3V to VCC + 0.3V INV Voltage ............................................... –0.3V to 3.6V Input Signal Power (Single-Ended, 50Ω) .............18dBm Input Signal Power (Differential, 50Ω) .................24dBm TJMAX .................................................................... 125°C Operating Temperature Range .................–40°C to 85°C Storage Temperature Range .................. –65°C to 125°C 24 23 22 21 20 19 DECA 1 18 VOA VCCA 2 17 RT1 VCCR 3 16 VODF 25 GND EN 4 15 VOS 13 VOB INV ENVB RP2 9 10 11 12 FLTB 8 IN 7 –B 14 RT2 DECB 6 IN+B VCCB 5 UF PACKAGE 24-LEAD (4mm s 4mm) PLASTIC QFN TJMAX = 125°C, θJA = 37°C/W EXPOSED PAD (PIN 25) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC5583IUF#PBF LTC5583IUF#TRPBF 5583 24-Lead (4mm × 4mm) Plastic QFN –40°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/ 5583fa 2 LTC5583 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C to 85°C, otherwise specifications are at TA = 25°C, VCC = 3.3V, EN = 3.3V. Test circuits are shown in Figures 1 and 2 (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS AC Input Input Frequency Range (Note 4) Input Impedance Differential 40 to 6000 MHz 400//0.5 Ω//pF fRF = 450MHz (Single-Ended Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) l RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) (Note 3) Deviation from CW Response 11dB Peak to Average Ratio (3-Carrier CDMA2K) 12dB Peak to Average Ratio (4-Carrier WCDMA) Input A to Input B Isolation Single-Ended Inputs lnput A to Output B Isolation Input B to Output A Isolation Single-Ended Inputs (Notes 6, 7) dB 57 dB –59 to 4 Output Slope Logarithmic Intercept 63 dBm 29.6 mV/dB –78.5 dBm 0.7 0.4 Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz dB dB 77 dB 50 >55 >55 dB dB dB 61 dB 56 dB fRF = 880MHz (Single-Ended Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) l RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) –58 to 3 Output Slope Logarithmic Intercept (Note 3) Deviation from CW Response 11dB Peak to Average Ratio (3-Carrier CDMA2K) 12dB Peak to Average Ratio (4-Carrier WCDMA) Input A to Input B Isolation Single-Ended inputs Input A to Output B Isolation Input B to Output A Isolation Single-Ended inputs (Notes 6, 7) dBm 29.7 mV/dB –77.8 dBm 0.7 0.4 Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz dB dB 68 dB 41 52 51 dB dB dB 60 dB 55 dB fRF = 2140MHz (Single-Ended Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) 50 l RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) Output Slope –58 to 2 dBm 26 29.6 34 mV/dB –90 –77.4 –64 dBm Logarithmic Intercept (Note 3) Channel Mismatch Input Power = 0dBm to Both Channels <1.25 dB Deviation from CW Response 11dB Peak to Average Ratio (3-Carrier CDMA2K) 12dB Peak to Average Ratio (4- Carrier WCDMA) 0.6 0.3 dB dB Input A to Input B Isolation Single-Ended Inputs 54 dB Input A to Output B Isolation Input B to Output A Isolation Single-Ended Inputs (Notes 6, 7) Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz 40 52 51 dB dB dB Differential Inputs (Notes 6, 7) Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz >55 >55 >55 dB dB dB 5583fa 3 LTC5583 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C to 85°C, otherwise specifications are at TA = 25°C, VCC = 3.3V, EN = 3.3V. Test circuits are shown in Figures 1 and 2 (Note 2). PARAMETER CONDITIONS MIN TYP MAX UNITS fRF = 2700MHz (Single-Ended Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) l RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) dB dB –56 to 3 Output Slope Logarithmic Intercept 59 52 (Note 3) dBm 30.0 mV/dB –74.9 dBm Deviation from CW Response 12dB Peak to Average Ratio (WiMAX OFDM) 0.6 dB Input A to Input B Isolation Single-Ended Inputs 52 dB lnput A to Output B Isolation Input B to Output A Isolation Singled-Ended Inputs (Notes 6, 7) Frequency Separation = 0Hz Frequency separation = 1MHz Frequency separation = 10MHz 33 45 44 dB dB dB Differential Inputs (Notes 6, 7) Frequency Separation = 0Hz Frequency separation = 1MHz Frequency separation = 10MHz 50 >55 >55 dB dB dB fRF = 3600MHz (Differential Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) l RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) dB dB –53 to 3 Output Slope Logarithmic Intercept 56 49 (Note 3) dBm 30.2 mV/dB –73.1 dBm Deviation from CW Response 12dB Peak to Average Ratio (WiMAX OFDM) 0.4 dB Input A to Input B Isolation Differential Inputs 70 dB lnput A to Output B Isolation Input B to Output A Isolation Differential Inputs (Notes 6, 7) 47 >55 >55 dB dB dB 49 dB Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz fRF = 5800MHz (Differential Inputs) Linear Dynamic Range CW, 50Ω, ±1dB Linearity Error (Note 5) RF Input Power Range CW, 50Ω, ±1dB Linearity Error (Note 5) l Output Slope 44 –44 to 5 dB dBm 31.3 mV/dB –63.2 dBm Logarithmic Intercept (Note 3) Deviation from CW Response 12dB Peak to Average Ratio (WiMAX OFDM) 0.5 dB Input A to Input B Isolation Differential Inputs 50 dB lnput A to Output B Isolation Input B to Output A Isolation Differential Inputs (Notes 6, 7) 30 42 41 dB dB dB Frequency Separation = 0Hz Frequency Separation = 1MHz Frequency Separation = 10MHz Output Interface VOA, VOB Output DC Voltage No RF Signal Present 0.45 V 50 Ω Source/Sink 5/5 mA Rise Time, 10% to 90% 0.5V to 2.2V, fRF = 100MHz, CFLTRA = CFLTRB = 8.2nF 140 ns Fall Time, 90% to 10% 2.2V to 0.5V, fRF = 100MHz, CFLTRA = CFLTRB = 8.2nF 3.5 μs Output Impedance IOUT 5583fa 4 LTC5583 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, –40°C to 85°C, otherwise specifications are at TA = 25°C, VCC = 3.3V, EN = 3.3V. Test circuits are shown in Figures 1 and 2 (Note 2). PARAMETER VODF CONDITIONS Output DC Voltage MIN ENVA ENVB MAX UNITS No RF Signal Present, VOS = 0V 0.05 5 Ω Source/Sink 5/5 mA Output Impedance IOUT TYP V Rise Time, 10% to 90% 50mV to 1.8V, fRF = 100MHz, CFLTRA = CFLTRB = 8.2nF 170 ns Fall Time, 90% to 10% 1.8V to 50mV, fRF = 100MHz, CFLTRA = CFLTRB = 8.2nF 3.5 μs Output DC Voltage No RF Signal Present 2.15 V Output Impedance 140 Ω IOUT Source/Sink 4.0/1.8 mA Rise Time, 10% to 90% 0.9V to 2.1V 11 ns Fall Time, 90% to 10% 2.1V to 0.9V –3dB Bandwidth 11 ns 50 MHz Control Interface EN Input High Voltage l Input Low Voltage l Input Current INV 2 Applied Voltage = 3.3V Input High Voltage V 100 VOS 180 μA V 1 Applied Voltage = 3.3V Input Voltage Range Input Current V 2 Input Low Voltage Input Current 0.3 0 0 Applied Voltage = 2.4V V μA 2.4 77 V μA Power Supply Supply Voltage 3.1 3.3 3.5 100 Supply Current Envelope Detectors Turned Off 80.5 Supply Current Envelope Detectors Turned On 90.1 Shutdown Current EN = 0V, VCC = 3.5V 0.1 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. Note 2: The LTC5583 is guaranteed functional over the temperature range from –40°C to 85°C. Note 3: Logarithmic Intercept is an extrapolated input power level from the best-fit log-linear straight line, where the output voltage is 0V. Note 4: Operation over a wider frequency range is possible with reduced performance. Consult the factory for information and assistance. Note 5: Linearity error is the difference in dB between the actual output and the best-fit straight line at 25°C (using linear regression between PIN = –50dBm and 0dBm for 450MHz, 880MHz, 2140MHz, 2700MHz; V mA mA 20 μA between PIN = –40dBm and 0dBm for 3600MHz, 5800MHz). The dynamic range is defined as the range of input power over which the linearity error is within ±1dB. Note 6: Input A to Output B (Channel A to Channel B) isolation is defined as the ratio of input power levels at the two channels when the interfering channel (Channel A with higher power) results in a 1dB output deviation in the interfered channel (Channel B with lower power) and vice versa. Sweep one channel input power level while holding the other channel input at –45dBm for 450MHz, 880MHz, 2140MHz, 2700MHz, 3600MHz, and at –35dBm for 5800MHz. Note 7: For frequency separation = 0Hz between the two input signals, channel-to-channel isolation is a function of the phase difference between these two signals. The worst-case isolation is assumed. 5583fa 5 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. Test circuits shown in Figures 1 and 2. Output Voltage vs RF Input Power CW Input at Various Frequencies 3 2.6 450MHz, CHA 880MHz, CHA 2140MHz, CHA 2700MHz, CHA 3600MHz, CHA 5800MHz, CHA 1.8 2 LINEARITY ERROR (dB) 2.2 VOA, VOB (V) Linearity Error vs RF Input Power CW Input at Various Frequencies 1.4 450MHz, CHB 880MHz, CHB 2140MHz, CHB 2700MHz, CHB 3600MHz, CHB 5800MHz, CHB 1.0 0.6 0.2 –70 –60 –50 –40 –30 –20 –10 INPUT POWER (dBm) 0 450MHz, CHA 880MHz, CHA 2140MHz, CHA 2700MHz, CHA 3600MHz, CHA 5800MHz, CHA –1 –2 450MHz, CHB 880MHz, CHB 2140MHz, CHB 2700MHz, CHB 3600MHz, CHB 5800MHz, CHB –3 –70 –60 –50 –40 –30 –20 –10 INPUT POWER (dBm) 10 0 1 0 5583 G02 5583 G01 Logarithmic Intercept vs Frequency Slope vs Frequency –59 33 –40°C –63 25°C 31 INTERCEPT (dBm) SLOPE (mV/dB) 32 85°C 30 29 –67 –40°C 25°C –71 85°C –75 –79 28 –83 27 0 1 2 3 4 FREQUENCY (GHz) 5 0 6 1 2 3 4 FREQUENCY (GHz) 5 Intercept Distribution vs Temperature 2140MHz CW Input Slope Distribution vs Temperature 2140MHz CW Input 35 85°C 25°C –40°C PERCENTAGE DISTRIBUTION (%) PERCENTAGE DISTRIBUTION (%) 40 35 30 25 20 15 10 5 6 5583 G04 5583 G03 45 10 30 85°C 25°C –40°C 25 20 15 10 5 0 0 28.5 30.3 29.1 29.7 SLOPE (mV/dB) 30.9 5583 G05 –83 –81 –79 –77 –75 –73 LOGARITHMIC INTERCEPT (dBm) –71 5583 G06 5583fa 6 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. For temperature compensation of logarithmic intercept at 880MHz, set RP1 = Open, RP2 = 0, RT1 = 11.5kΩ, RT2 = 1.13kΩ. See Figure 1. Output Voltage and Linearity Error Difference Output and Linearity vs RF Input Power, 880MHz CW Error vs RF Input Power, 880MHz Inputs, Single-Ended Drive CW Inputs, Single-Ended Drive 2.5 2.5 2.5 1.5 VOA, VOB (V) 0.5 0 –0.5 1.0 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B 0.5 0 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –1.0 1.0 1.5 0.5 1.0 –0.5 0 –1.0 –1.5 0.5 SWEEP CH A INPUT HOLD CH B INPUT = –26dBm –2.0 –2.5 0 –65 5 –55 –1.5 85°C 25°C –40°C –45 –35 –25 –15 INPUT POWER (dBm) –5 5583 G07 –2.0 –2.5 5 5583 G08 Modulation Deviation vs RF Input Power, 880MHz Inputs, Single-Ended Drive Output Voltage and Linearity Error vs RF Input Power, 880MHz CW Inputs, Single-Ended Drive, 5 Devices 2.5 2.5 1.5 LINEARITY ERROR (dB) 1.5 LINEARITY ERROR (dB) 1.0 2.0 SWEEP CH B INPUT HOLD CH A INPUT = –26dBm 2.0 VODF (V) 2.0 2.5 VOS = 1.2V, INV = 0V 2.0 3 2.0 0.5 1.5 0 –0.5 1.0 –1.0 0.5 0 –65 –1.5 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 LINEARITY ERROR (dB) 1.0 VOA, VOB (V) 2 1.5 LINEARITY ERROR (dB) 2.0 1 4-CARRIER WCDMA –1 –2 –2.0 –2.5 CW 0 3-CARRIER CDMA2K DEVIATION MEASURED FROM LINEAR REFERENCE GENERATED WITH CW INPUT. –3 –65 5 –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 5583 G09 5583 G10 3 0.09 2 0.06 1 0.03 0 0 –0.03 –1 –3 –65 –0.06 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –0.09 5 5583 G11 INTERFERED CHANNEL OUTPUT DEVIATION (dB) Input A to Output B Isolation, Input B to Output A Isolation, 880MHz CW Inputs, Single-Ended Drive VOA – VOB (V) VOA – VOB (dB) Channel Matching vs RF Input Power, 880MHz CW Inputs, Single-Ended Drive, 5 Devices –2 5 2.5 2.0 A m B, FREQ SEP = 0Hz B m A, FREQ SEP = 0Hz A m B, FREQ SEP = 1MHz B m A, FREQ SEP = 1MHz A m B, FREQ SEP = 10MHz B m A, FREQ SEP = 10MHz NOTE 7 A m B INDICATES: CH A = INTERFERING CHANNEL CH B = INTERFERED CHANNEL B m A INDICATES: CH B = INTERFERING CHANNEL CH A = INTERFERED CHANNEL 1.5 INTERFERED CHANNEL INPUT = –45dBm, INTERFERING CHANNEL INPUT SWEPT 1.0 0.5 0 –45 FREQ SEP = FREQUENCY SEPARATION BETWEEN CH A INPUT AND CH B INPUT –35 –25 –15 –5 INTERFERING CHANNEL INPUT POWER (dBm) 5 5583 G12 5583fa 7 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. For temperature compensation of logarithmic intercept at 2140MHz, set RP1 = Open, RP2 = 0, RT1 = 9.76kΩ, RT2 = 1.1kΩ. See Figure 1. Difference Output and Linearity Error vs RF Input Power, 2140MHz CW Inputs, Single-Ended Drive Output Voltage and Linearity Error vs RF Input Power, 2140MHz CW Inputs, Single-Ended Drive 2.5 2.5 2.5 1.5 VOA, VOB (V) 0 –0.5 1.0 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B 0.5 0 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –1.0 1.0 1.5 0.5 1.0 –0.5 0 –1.0 –1.5 0.5 SWEEP CH A INPUT HOLD CH B INPUT = –26dBm –2.0 –2.5 0 –65 5 –55 –45 –35 –25 –15 INPUT POWER (dBm) –1.5 85°C 25°C –40°C –5 5583 G13 –2.0 –2.5 5 5583 G14 Output Voltage and Linearity Error vs RF Input Power, 2140MHz CW Inputs, Single-Ended Drive, 5 Devices Modulation Deviation vs RF Input Power, 2140MHz Inputs, Single-Ended Drive 2.5 2.5 1.5 LINEARITY ERROR (dB) 0.5 1.5 LINEARITY ERROR (dB) 1.0 2.0 SWEEP CH B INPUT HOLD CH A INPUT = –26dBm 2.0 VODF (V) 2.0 2.5 VOS = 1.2V, INV = 0V 2.0 3 2.0 2.0 0.5 0 –0.5 1.0 –1.0 0.5 0 –65 –1.5 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 LINEARITY ERROR (dB) 1.5 LINEARITY ERROR (dB) 1.0 VOA, VOB (V) 2 1.5 1 4-CARRIER WCDMA CW 0 3-CARRIER CDMA2K –1 –2 DEVIATION MEASURED FROM LINEAR REFERENCE GENERATED WITH CW INPUT. –3 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –2.0 –2.5 5 –5 5583 G15 5583 G16 3 0.09 2 0.06 1 0.03 0 0 –0.03 –1 –3 –65 –0.06 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –0.09 5 5583 G17 INTERFERED CHANNEL OUTPUT DEVIATION (dB) Input A to Output B Isolation, Input B to Output A Isolation, 2140MHz CW Inputs, Single-Ended Drive VOA – VOB (V) VOA – VOB (dB) Channel Matching vs RF Input Power, 2140MHz CW Inputs, Single-Ended Drive, 5 Devices –2 5 2.5 2.0 A m B, FREQ SEP = 0Hz B m A, FREQ SEP = 0Hz A m B, FREQ SEP = 1MHz B m A, FREQ SEP = 1MHz A m B, FREQ SEP = 10MHz B m A, FREQ SEP = 10MHz NOTE 7 A m B INDICATES: CH A = INTERFERING CHANNEL CH B = INTERFERED CHANNEL B m A INDICATES: CH B = INTERFERING CHANNEL CH A = INTERFERED CHANNEL 1.5 INTERFERED CHANNEL INPUT = –45dBm, INTERFERING CHANNEL INPUT SWEPT 1.0 0.5 0 –45 FREQ SEP = FREQUENCY SEPARATION BETWEEN CH A INPUT AND CH B INPUT –35 –25 –15 –5 INTERFERING CHANNEL INPUT POWER (dBm) 5 5583 G18 5583fa 8 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. For temperature compensation of logarithmic intercept at 2700MHz, set RP1 = Open, RP2 = 0, RT1 = 8.87kΩ, RT2 = 1.21kΩ. See Figure 1. Difference Output and Linearity Error vs RF Input Power, 2700MHz CW Inputs, Single-Ended Drive Output Voltage and Linearity Error vs RF Input Power, 2700MHz CW Inputs, Single-Ended Drive 2.5 2.5 2.5 1.5 VOA, VOB (V) 0.5 0 –0.5 1.0 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B 0.5 0 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –1.0 1.0 1.5 0.5 1.0 –0.5 0 –1.0 –1.5 0.5 SWEEP CH A INPUT HOLD CH B INPUT = –25dBm –2.0 0 –65 –2.5 –5 5 –55 –1.5 85°C 25°C –40°C –45 –35 –25 –15 INPUT POWER (dBm) –5 5583 G19 –2.0 –2.5 5 5583 G20 Output Voltage and Linearity Error vs RF Input Power, 2700MHz CW Inputs, Single-Ended Drive, 5 Devices Modulation Deviation vs RF Input Power, 2700MHz Inputs, Single-Ended Drive 2.5 2.5 1.5 LINEARITY ERROR (dB) 1.5 LINEARITY ERROR (dB) 1.0 2.0 SWEEP CH B INPUT HOLD CH A INPUT = –25dBm 2.0 VODF (V) 2.0 2.5 VOS = 1.2V, INV = 0V 2.0 3 2.0 0 –0.5 1.0 –1.0 0.5 0 –65 –1.5 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 LINEARITY ERROR (dB) 0.5 1.5 LINEARITY ERROR (dB) 1.0 VOA, VOB (V) 2 1.5 2.0 1 CW 0 WiMAX –1 –2 DEVIATION MEASURED FROM LINEAR REFERENCE GENERATED WITH CW INPUT. –3 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –2.0 –2.5 5 5583 G22 Input A to Output B Isolation, Input B to Output A Isolation, 2700MHz CW Inputs, Single-Ended Drive 0.09 2 0.06 1 0.03 0 0 –0.03 –1 –3 –65 –0.06 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –0.09 5 5583 G23 VOA – VOB (V) VOA – VOB (dB) 3 INTERFERED CHANNEL OUTPUT DEVIATION (dB) Channel Matching vs RF Input Power, 2700MHz CW Inputs, Single-Ended Drive, 5 Devices –2 5 –5 5583 G21 5.0 4.5 4.0 3.5 A m B, FREQ SEP = 0Hz NOTE 7 B m A, FREQ SEP = 0Hz A m B, FREQ SEP = 1MHz B m A, FREQ SEP = 1MHz A m B, FREQ SEP = 10MHz B m A, FREQ SEP = 10MHz A m B INDICATES: CH A = INTERFERING CHANNEL CH B = INTERFERED CHANNEL B m A INDICATES: CH B = INTERFERING CHANNEL CH A = INTERFERED CHANNEL 3.0 2.5 INTERFERED CHANNEL INPUT = –45dBm, INTERFERING CHANNEL INPUT SWEPT 2.0 1.5 1.0 FREQ SEP = FREQUENCY SEPARATION BETWEEN CH A INPUT AND CH B INPUT 0.5 0 –45 –35 –25 –15 –5 INTERFERING CHANNEL INPUT POWER (dBm) 5 5583 G24 5583fa 9 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. For temperature compensation of logarithmic intercept at 3600MHz, set RP1 = Open, RP2 = 0, RT1 = 10.2kΩ, RT2 = 1.65kΩ. See Figure 2. Difference Output and Linearity Error vs RF Input Power, 3600MHz CW Inputs, Differential Drive Output Voltage and Linearity Error vs RF Input Power, 3600MHz CW Inputs, Differential Drive 2.5 2.5 2.5 VOA, VOB (V) 0.5 0 –0.5 1.0 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B 0.5 0 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –1.0 1.0 1.5 0.5 1.0 –0.5 0 –1.0 0.5 –1.5 SWEEP CH A INPUT HOLD CH B INPUT = –25dBm –2.0 0 –65 –2.5 –5 5 –55 –1.5 85°C 25°C –40°C –45 –35 –25 –15 INPUT POWER (dBm) –5 –2.0 –2.5 5 5583 G26 5583 G25 Modulation Deviation vs RF Input Power, 3600MHz Inputs, Differential Drive Output Voltage and Linearity Error vs RF Input Power, 3600MHz CW Inputs, Differential Drive, 3 Devices 3 2.5 2.5 1.5 LINEARITY ERROR (dB) 1.5 LINEARITY ERROR (dB) 1.0 2.0 SWEEP CH B INPUT HOLD CH A INPUT = –25dBm 2.0 1.5 VODF (V) 2.0 2.5 VOS = 1.2V, INV = 0V 2.0 2.0 0 –0.5 1.0 –1.0 0.5 0 –65 –1.5 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 LINEARITY ERROR (dB) 0.5 1.5 LINEARITY ERROR (dB) 1.0 VOA, VOB (V) 2 1.5 2.0 1 CW 0 WiMAX –1 –2 DEVIATION MEASURED FROM LINEAR REFERENCE GENERATED WITH CW INPUT. –3 –65 –55 –45 –35 –25 –15 INPUT POWER (dBm) –2.0 –2.5 5 –5 5583 G28 5583 G27 3 0.09 2 0.06 1 0.03 0 0 –0.03 –1 –3 –65 –0.06 85°C 25°C –40°C –55 –45 –35 –25 –15 INPUT POWER (dBm) –5 –0.09 5 5583 G29 INTERFERED CHANNEL OUTPUT DEVIATION (dB) Input A to Output B Isolation, Input B to Output A Isolation, 3600MHz CW Inputs, Differential Drive VOA – VOB (V) VOA – VOB (dB) Channel Matching vs RF Input Power, 3600MHz CW Inputs, Differential Drive, 3 Devices –2 5 2.5 2.0 A m B, FREQ SEP = 0Hz B m A, FREQ SEP = 0Hz A m B, FREQ SEP = 1MHz B m A, FREQ SEP = 1MHz A m B, FREQ SEP = 10MHz B m A, FREQ SEP = 10MHz A m B INDICATES: CH A = INTERFERING CHANNEL CH B = INTERFERED CHANNEL B m A INDICATES: CH B = INTERFERING CHANNEL CH A = INTERFERED CHANNEL 1.5 1.0 INTERFERED CHANNEL INPUT = –45dBm, INTERFERING CHANNEL INPUT SWEPT NOTE 7 0.5 0 –45 FREQ SEP = FREQUENCY SEPARATION BETWEEN CH A INPUT AND CH B INPUT –35 –25 –15 –5 INTERFERING CHANNEL INPUT POWER (dBm) 5 5583 G30 5583fa 10 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. For temperature compensation of logarithmic intercept at 5800MHz, set RP1 = Open, RP2 = 0, RT1 = 10kΩ, RT2 = 1.47kΩ. See Figure 2. Output Voltage and Linearity Error vs RF Input Power, 5800MHz CW Inputs, Differential Drive Difference Output and Linearity Error vs RF Input Power, 5800MHz CW Inputs, Differential Drive 2.5 2.5 2.5 VOA, VOB (V) 0.5 0 –0.5 1.0 85°C, CH A 85°C, CH B 25°C, CH A 25°C, CH B –40°C, CH A –40°C, CH B 0.5 0 –55 –45 –1.0 1.0 1.5 0.5 1.0 –0.5 0 –1.0 0.5 –1.5 SWEEP CH A INPUT HOLD CH B INPUT = –20dBm –2.0 0 –55 –2.5 5 10 –35 –25 –15 –5 INPUT POWER (dBm) 1.5 –45 LINEARITY ERROR (dB) 1.5 LINEARITY ERROR (dB) 1.0 2.0 SWEEP CH B INPUT HOLD CH A INPUT = –20dBm 2.0 1.5 VODF (V) 2.0 2.5 VOS = 1.2V, INV = 0V 2.0 –1.5 85°C 25°C –40°C –2.0 –2.5 5 10 –35 –25 –15 –5 INPUT POWER (dBm) 5583 G32 5583 G31 Output Voltage and Linearity Error vs RF Input Power, 5800MHz CW Inputs, Differential Drive, 3 Devices Modulation Deviation vs RF Input Power, 5800MHz Inputs, Differential Drive 2.5 2.5 3 2.0 2 LINEARITY ERROR (dB) VOA, VOB (V) 1.0 0.5 1.5 0 –0.5 1.0 –1.0 0.5 0 –55 –1.5 85°C 25°C –40°C –45 –35 –25 –15 –5 INPUT POWER (dBm) LINEARITY ERROR (dB) 1.5 2.0 1 CW 0 WiMAX –1 –2 DEVIATION MEASURED FROM LINEAR REFERENCE GENERATED WITH CW INPUT. –3 –55 –45 –35 –25 –15 –5 INPUT POWER (dBm) –2.0 –2.5 5 10 5583 G33 5583 G34 3 0.09 2 0.06 1 0.03 0 0 –0.03 –1 –3 –55 85°C 25°C –40°C –45 –35 –25 –15 –5 INPUT POWER (dBm) 5 10 5583 G35 –0.06 –0.09 INTERFERED CHANNEL OUTPUT DEVIATION (dB) Input A to Output B Isolation, Input B to Output A Isolation, 5800MHz CW Inputs, Differential Drive VOA – VOB (V) VOA – VOB (dB) Channel Matching vs RF Input Power, 5800MHz CW Inputs, Differential Drive, 3 Devices –2 5 10 2.5 2.0 1.5 A m B, FREQ SEP = 0Hz NOTE 7 B m A, FREQ SEP = 0Hz A m B, FREQ SEP = 1MHz B m A, FREQ SEP = 1MHz A m B, FREQ SEP = 10MHz B m A, FREQ SEP = 10MHz A m B INDICATES: CH A = INTERFERING CHANNEL CH B = INTERFERED CHANNEL B m A INDICATES: CH B = INTERFERING CHANNEL CH A = INTERFERED CHANNEL INTERFERED CHANNEL INPUT = –35dBm, INTERFERING CHANNEL INPUT SWEPT 1.0 0.5 0 –35 –30 –25 –20 –15 –10 –5 0 INTERFERING CHANNEL INPUT POWER (dBm) FREQ SEP = FREQUENCY SEPARATION BETWEEN CH A INPUT AND CH B INPUT 5 10 5583 G36 5583fa 11 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. Test circuits shown in Figures 1 and 2. Input A to Input B Isolation, Differential Inputs –40 –40 –50 –50 ISOLATION (dB) ISOLATION (dB) Input A to Input B Isolation, Single-Ended Inputs –60 –70 –60 –70 –80 –80 –90 –90 0 0.5 1 1.5 2 FREQUENCY (GHz) 2 3 2.5 2.5 3 3.5 4 4.5 5 FREQUENCY (GHz) 5583 G38 5583 G37 Output Response to RF Burst Input, 100MHz CW Input, CFLTRA = CFLTRB = 8.2nF 3.4 Output Response to RF Burst Input, 100MHz CW Input, CFLTRA = CFLTRB = 1μF 3.4 RF BURST ON 3.0 RF BURST ON 3.0 2.6 2.6 RF BURST OFF INPUT = 0dBm INPUT = –10dBm INPUT = –20dBm INPUT = –30dBm INPUT = –40dBm INPUT = –50dBm 1.8 1.4 1.4 1.0 0.6 0.6 0.2 1 2 3 4 5 6 TIME (μs) 7 8 0.2 10 9 INPUT = 0dBm INPUT = –10dBm INPUT = –20dBm INPUT = –30dBm INPUT = –40dBm INPUT = –50dBm 1.8 1.0 0 RF BURST OFF 2.2 VOA (V) 2.2 VOA (V) 6 5.5 0 1 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 TIME (ms) 5583 G39 5583 G40 Supply Current vs Supply Voltage Envelope Detectors Disabled Supply Current vs Supply Voltage Envelope Detectors Enabled 110 100 85°C 105 85°C 100 90 ICC (mA) ICC (mA) 95 25°C 80 70 –40°C 25°C 90 85 80 75 60 70 50 60 –40°C 65 3.1 3.2 3.3 VCC (V) 3.4 3.5 5583 G41 3.1 3.2 3.3 VCC (V) 3.4 3.5 5583 G42 5583fa 12 LTC5583 TYPICAL PERFORMANCE CHARACTERISTICS VCC = 3.3V, EN = 3.3V, TA = 25°C, unless otherwise noted. Test circuits shown in Figures 1 and 2. Envelope Detector Peak Output Supply Current vs RF Input Power, Voltage vs Crest Factor, 2140MHz CW Inputs to Both Channels 2140MHz Input 100 2.15 ENVELOPE DETECTORS ENABLED 2.05 ENVA PEAK VALUE (V) ICC (mA) 90 AVERAGE INPUT POWER –10dBm –20dBm –30dBm –40dBm 2.10 80 ENVELOPE DETECTORS DISABLED 70 2.00 1.95 1.90 1.85 60 1.80 50 –70 –60 1.75 0 5 –50 –40 –30 –20 –10 INPUT POWER (dBm) 1 5583 G43 2.2 0.14 0.12 2.1 0.12 2.0 0.10 2.0 0.10 1.9 0.08 1.9 0.08 1.8 0.06 1.8 0.06 1.7 0.04 ENVA (V) 0.14 2.1 1.7 0.04 1.6 0.02 1.6 0.02 1.5 0 1.5 0 1.4 –0.02 1.4 –0.02 1.3 –0.04 1.3 –0.04 –0.06 1.2 –0.06 1 2 3 4 5 TIME (μs) 5583 G46 CREST FACTOR = 10, OSCILLOSCOPE WAVEFORM ACQUIRED IN AVERAGE MODE 2 3 4 5 TIME (μs) 5583 G45 CREST FACTOR = 6 OSCILLOSCOPE WAVEFORM ACQUIRED IN AVERAGE MODE 0 Envelope Detector Output Over Temperature, 2140MHz Input Average Power = –30dBm Envelope Detector Output Over Temperature, 2140MHz Input Average Power = –30dBm 0 1 2.25 2.20 2.20 2.15 2.15 2.10 2.10 ENVA (V) 2.25 2.05 2.00 INPUT SIGNAL (V) 2.2 1.2 ENVA (V) 3 4 5 6 7 8 9 10 11 12 PEAK TO AVERAGE POWER RATIO 5583 G44 (CREST FACTOR) Envelope Detector Output and Input Signal Envelope, 100MHz Input Average Power = –30dBm INPUT SIGNAL (V) ENVA (V) Envelope Detector Output and Input Signal Envelope, 100MHz Input Average Power = –30dBm 2 2.05 2.00 1.95 1.95 1.90 PEAK 85°C 25°C –40°C 1.85 1.80 0 1 CREST FACTOR = 6 OSCILLOSCOPE WAVEFORM ACQUIRED IN AVERAGE MODE 2 3 TIME (μs) 4 5 5583 G47 CREST FACTOR = 10 OSCILLOSCOPE WAVEFORM ACQUIRED IN AVERAGE MODE 1.90 85°C 25°C –40°C 1.85 PEAK 1.80 0 1 2 3 TIME (μs) 4 5 5583 G48 5583fa 13 LTC5583 PIN FUNCTIONS DECA, DECB (Pins 1, 6): Input Common Mode Decoupling Pins for Channel A and Channel B. These pins are internally biased to 1.6V. The input impedance is 1.75kΩ in parallel with a 40pF internal shunt capacitor to ground. The impedance between DECA and IN+A (or IN–A) is 200Ω. The pin can be connected to the center tap of an external balun or to a capacitor to ground. VCCA, VCCB, VCCR (Pins 2, 5, 3): Power Supply Pins for Channel A, Channel B, and Bias Circuits. Typical total current consumption of these pins is 81mA. Each of these pins should be bypassed with 1nF and 1μF capacitors, placed as close to the IC as possible. EN (Pin 4): Enable Input Pin. An applied voltage above 2V will activate the bias for the IC. For an applied voltage below 0.3V, the circuit will be shut down (disabled) with a corresponding reduction in power supply current. If the enable function is not required, then this pin can be connected to VCC. The applied voltage to this pin should not exceed VCC by more than 0.3V. RP2 (Pin 9): Pin for Setting Polarity of Second Order Output Temperature Compensation. Connect this pin to ground to change the output voltage inversely proportional to ambient temperature. Float this pin to change the output voltage proportional to ambient temperature. INV (Pin 12): Control Input Pin to Invert the Polarity of the Difference Output VODF. RT2 (Pin 14): Second Order Output Temperature Compensation Pin for Both Channels. Connect this pin to ground to disable. The output voltage will increase or decrease with the ambient temperature by connecting this pin to ground via an off-chip resistor, depending on the polarity set by RP2 pin. VOS (Pin 15): Input Pin for Setting the DC Offset of the Difference Output VODF. It is recommended to set this DC offset such that VODF does not fall below 100mV. VODF (Pin 16): DC Difference Output. This voltage is equal to the difference of the two channels’ output voltages, plus a DC offset: RT1 (Pin 17): First Order Output Temperature Compensation Pin for Both Channels. Connect this pin to ground to disable. The output voltage will increase or decrease with the ambient temperature by connecting this pin to ground via an off-chip resistor, depending on the polarity set by RP1 pin. VOA, VOB (Pins 18, 13): DC Output of Channel A and Channel B, respectively. VCCN (Pin 19): Power Supply Pin for the Envelope Detectors in Both Channels. Typical total current consumption of this pin is 9.6mA. This pin should be bypassed with 1nF and 1μF capacitors. Connect this pin to ground to disable the envelope detectors. ENVA, ENVB (Pins 20, 11): Envelope Detector Output Pins for Channel A and Channel B, respectively. Each output tracks the input signal’s RF envelope and outputs a DC voltage directly proportional to the signal power, normalized to the average power. FLTA, FLTB (Pins 21, 10): Connection for an External Filtering Capacitor for Channel A and Channel B, respectively. A minimum 8nF capacitor is required for stable AC average power measurement. Each capacitor should be connected between FLTA and VCCA, and between FLTB and VCCB. RP1 (Pin 22): Pin for Setting Polarity of First Order Output Temperature Compensation. Connect this pin to ground to change the output voltage proportional to ambient temperature. Float this pin to change the output voltage inversely proportional to ambient temperature. IN+A, IN–A, IN+B, IN–B (Pins 24, 23, 7, 8): Differential RF Input Signal Pins for Channel A and Channel B. Each channel can be driven with a single-ended or differential signal. These pins are internally biased to 1.6V and should be DC-blocked externally. The differential impedance is 400Ω. GND (Exposed Pad Pin 25): Circuit Ground Return for the Entire IC. This must be soldered to the printed circuit board ground plane. VODF = (VOA – VOB) + VOS, if INV pin is held low, (<1V) VODF = (VOB – VOA) + VOS, if INV pin is held high, (>2V) 5583fa 14 LTC5583 TEST CIRCUITS R1 1Ω VCC 3.3V 1μF 100pF 1nF 20pF 1nF 1nF RF INPUT A CFLTRA 100nF VCC 1nF 75Ω RP1 24 0.3pF IN+A 20pF 1nF 1 2 3 VCC 1nF 4 5 VCC 1nF 6 22 21 RP1 FLTA 20 19 ENVA VCCN LTC5583 DECA VOUTA VCCA RT1 VCCR VODF EXPOSED PAD 25 EN VOS VCCB RT2 DECB VOUTB 18 1nF RT1 17 16 15 1nF 14 RT2 13 20pF 1nF IN+B 7 1nF RF INPUT B 23 IN–A IN–B 8 75Ω RP2 9 FLTB ENVB 10 11 INV 12 1nF RP2 0.3pF 1nF 20pF CFLTRB 100nF 100pF 5583 F01 COMP VALUE SIZE PART NUMBER C 20pF 0402 Murata GRM1555CIH200JB01 C 100pF 0402 Murata GRM1555CIH101JDO1B C 1nF 0402 Murata GRM155R71H102KA01D C 100nF 0402 Murata GRM155R61A104KA01 C 1μF 0402 Murata GRM155R60J105KE19 R 75Ω 0402 Vishay CRCW040275R0FKED FREQUENCY RP1 RP2 RT1 RT2 INPUT RETURN LOSS 450MHz Open 0Ω 11.5kΩ 1.13kΩ 21dB 880MHz Open 0Ω 11.5kΩ 1.13kΩ 14dB 2140MHz Open 0Ω 9.76kΩ 1.10kΩ 14dB 2700MHz Open 0Ω 8.87kΩ 1.21kΩ 14dB Figure 1. Test Circuit Optimized for 40MHz to 3GHz Operation in Single-Ended Input Configuration 5583fa 15 LTC5583 TEST CIRCUITS RF INPUT A VCC T1 1:1 L1 CFLTRA 100nF 1nF 1 3 C1 2 5 62Ω 24 TDK HHM17XX 1 20pF 1nF 2 3 VCC 1nF 20pF 1nF 1 2 5 6 23 IN–A 22 RP1 21 FLTA 20 ENVA LTC5583 DECA 19 VCCN VOUTA VCCA RT1 VCCR VODF EXPOSED PAD 25 EN VOS VCCB RT2 DECB VOUTB IN+B 7 3 C2 4 5 VCC T2 1:1 L2 3.3V 1μF RP1 IN+A RF INPUT B VCC 1nF 4 1nF R1 1Ω 100pF IN–B 8 RP2 9 RP2 62Ω 4 FLTB ENVB 10 11 18 1nF RT1 17 16 1nF 15 14 RT2 13 INV 12 1nF CFLTRB 100nF 100pF TDK HHM17XX 5583 F02 COMP VALUE SIZE PART NUMBER C 20pF 0402 Murata GRM1555CIH200JB01 C 100pF 0402 Murata GRM1555CIH101JD01B C 1nF 0402 Murata GRM155R71H102KA01D C 100nF 0402 Murata GRM155R61A104KA01 C 1μF 0402 Murata GRM155R60J105KE19 R 62Ω 0402 Vishay CRCW040262R0FKED FREQUENCY L1, L2 C1, C2 T1, T2 RP1 RP2 RT1 RT2 INPUT RETURN LOSS 2140MHz 2.7nH 1pF Murata LDB212G1005C-001 Open 0 9.76kΩ 1.10kΩ 15dB 2700MHz 1.5nH X TDK_HHM1710J1 Open 0 8.87kΩ 1.21kΩ 15dB 3600MHz 1.2nH 0.3pF TDK_HHM1727D1 Open 0 10.2kΩ 1.65kΩ 17dB 5800MHz Short 0.3pF TDK_HHM1733B1 Open 0 10.0kΩ 1.47kΩ 11dB Figure 2. Test Circuit Optimized for 2GHz to 6GHz Operation in Differential Input Configuration 5583fa 16 LTC5583 TEST CIRCUITS Figure 3. Top Side of Evaluation Board for Single-Ended Input Configuration 5583fa 17 LTC5583 APPLICATIONS INFORMATION The LTC5583 is a dual-channel true RMS power detector, capable of measuring two RF signals over the frequency range from 40MHz to 6GHz, independent of input waveforms with different crest factors such as CW, CDMA2K, WCDMA, LTE and WiMAX signals. Up to 60dB dynamic range is achieved with very stable output over the full temperature range from –40°C to 85°C. Input sensitivity can be as low as –56dBm up to 2.7GHz even with singleended 50Ω input termination. Table 1. Single-Ended Input Impedance S11 FREQUENCY (MHz) INPUT IMPEDANCE (Ω) MAG ANGLE (°) 40 207.4 – j15.5 0.613 –2.2 100 193.0 – j34.0 0.599 –5.4 200 188.9 – j56.8 0.611 –8.9 400 151.6 – j68.7 0.576 –15.2 600 127.8 – j62.8 0.530 –19.5 800 107.6 – j66.0 0.513 –26.2 1000 96.1 – j61.5 0.485 –30.3 1200 85.6 – j59.2 0.467 –35.4 The differential RF inputs are internally biased at 1.6V. The differential impedance is about 400Ω. These pins should be DC blocked when connected to ground or other matching components. 1400 76.2 – j57.4 0.455 –41.0 1600 67.7 – j55.0 0.445 –47.1 1800 60.4 – j52.0 0.435 –53.5 2000 54.9 – j48.7 0.423 –59.4 The LTC5583 can be driven in a single-ended configuration. The single-ended input impedance vs frequency is given in Table 1. Figure 4 shows the simplified circuit of this single-ended configuration for each channel. The DECA pin can be either left floating or AC-coupled to ground via an external capacitor. While the RF signal is applied to the IN+A (or IN–A) pin, the other pin, IN–A (or IN+A), should be AC-coupled to ground. By simply terminating the signal side of the inputs with a 75Ω resistor in front of the AC-blocking capacitor and coupling the other side to ground using a 1nF capacitor, a broadband 50Ω input match can be achieved with typical input return loss better than 14dB from 40MHz to 2.7GHz. At higher RF frequencies, additional matching components may be needed. Contact LTC Applications for more information. 2200 50.3 – j45.6 0.414 –65.2 2400 46.5 – j42.7 0.406 –70.8 2600 43.7 – j39.8 0.396 –76.0 2800 41.6 – j37.0 0.384 –80.8 3000 40.2 – j34.5 0.371 –84.9 3200 39.3 – j32.0 0.356 –88.8 3400 37.8 – j30.1 0.350 –93.1 3600 35.6 – j26.4 0.336 –101.5 3800 35.0 – j23.3 0.314 –107.4 4000 34.4 – j19.8 0.291 –115.0 4200 33.6 – j16.7 0.275 –123.2 4400 32.9 – j14.2 0.264 –130.6 4600 31.7 – j11.1 0.260 –141.0 4800 30.5 – j8.0 0.261 –152.0 5000 29.3 – j5.1 0.268 –162.5 5200 28.0 – j2.1 0.283 –173.0 5400 26.7 + j0.5 0.304 178.4 5600 25.4 + j2.7 0.328 171.7 5800 24.2 + j4.8 0.353 165.8 6000 23.1 + j6.6 0.377 161.1 RF Inputs 5583fa 18 LTC5583 APPLICATIONS INFORMATION LTC5583 1nF RF INPUT IN+A 24 R1 75Ω 0.3pF 200Ω 1 1nF DECA 40pF 20pF 200Ω 23 1nF IN–A 20pF 5583 F04 Figure 4. Single-Ended Input Configuration LTC5583 RF INPUT J1 T1 1:1 TDK HHM17xx L1 1 IN+A 24 3 200Ω C5 2 5 1 R1 62Ω DECA 40pF 200Ω 4 23 IN–A C4 1nF C6 20pF 5583 F05 Figure 5. Differential Input Configuration MATCHING NETWORK CS1 RF INPUT TO IN+ CS1 LM TO IN– 5583 F06 Figure 6. Single-Ended to Differential Conversion 5583fa 19 LTC5583 APPLICATIONS INFORMATION The LTC5583 differential inputs can also be driven from a fully balanced source as shown in Figure 5. When the two input sources are single-ended, conversion to differential signals can improve channel-to-channel isolation to obtain accurate outputs from the dual channels, particularly at very high frequencies (i.e. 3.6GHz and above). This can be achieved using a 1:1 balun to match the chip’s internal 400Ω input impedance to the 50Ω source by adding a 62Ω resistor (R1) at the differential inputs as shown in Figure 5. Since there is no voltage conversion gain from impedance transformation in this case, the sensitivity of the detector is similar to the one using single-ended inputs as shown in Figure 4. dynamic range can also be shifted to tailor to a particular application. By simply inserting an attenuator in front of the RF input, the power range is shifted higher by the amount of the attenuation. If better sensitivity is needed, a 1:4 balun can be used and R1 should be increased to 400Ω correspondingly to match 200Ω input impedance to the 50Ω source. This impedance transformation results in 6dB voltage gain, thus 6dB improvement in sensitivity is obtained while the overall dynamic range remains the same. At high frequency, additional LC elements may be needed for input impedance matching due to the parasitics of the transformer and PCB traces. These pins are internally biased at VCC – 0.43V via a 1.2k resistor from the VCCA and VCCB voltage supply. To ensure stable operation of the LTC5583, an external capacitor with a value of 8nF or higher is required to connect the FLTA pin to VCCA, and the FLTB pin to VCCB, respectively. Do not connect these filter capacitors to ground or any other low voltage reference to prevent an abnormal startup condition. Alternatively, a narrowband LC matching network can be used for the conversion of a single-ended signal to a balanced signal. Such a matching network is shown in Figure 6. By this means, the sensitivity and overall linear dynamic range of the detector can be similar to the one using a 1:4 RF input balun, as described above. For a 50Ω input termination, the approximate RF input power range of the LTC5583 is from –58dBm to 4dBm, even with high crest factor signals such as a 4-carrier WCDMA waveform, but the minimum detectable RF power level varies as the input RF frequency increases. The linear The sensitivity of LTC5583 is dictated by the broadband input noise power, which also determines the output DC offset voltage. When the inputs are terminated differently, the DC output voltage may vary slightly. When the input noise power is minimized, the DC offset voltage is also reduced to a minimum, and the sensitivity and dynamic range are improved accordingly. External Filtering Capacitors at FLTA and FLTB Pins The value of these two filtering capacitors has a dominant effect on the output transient response. The lower the capacitance, the faster the output rise and fall times. For signals with AM content such as W-CDMA, ripple can be observed when the loop bandwidth set by the filtering capacitors is close to the modulation bandwidth of the signal. In general, the LTC5583 output ripple remains relatively constant regardless of the RF input power level for a fixed filtering capacitor and modulation format of the RF signal. Typically, this capacitor must be selected to average out the ripple to achieve the desired accuracy of RF power measurement. 5583fa 20 LTC5583 APPLICATIONS INFORMATION RMS Power Detector Output: VOA, VOB The output buffer amplifier of the LTC5583 is shown in Figure 7. This Class-AB buffer amplifier can output ±5mA current to the load. The output impedance is determined primarily by the 50Ω series resistor connected to the buffer amplifier inside the chip. This will prevent any overstress on the internal devices in the event that the output is shorted to ground. The –3dB small-signal bandwidth of the buffer amplifier is about 22.4MHz and the full-scale rise/fall time can be as fast as 140ns, limited by the slew rate of the internal circuit instead. When the output is resistively terminated or open, the fastest output transient response is achieved when a large signal is applied to the RF input. The rise time of the LTC5583 is about 140ns and the fall time is 3.5μs, respectively, for full-scale pulsed RF input power with 8.2nF filtering capacitors. The speed of the output transient response is dictated mainly by the filtering capacitors (at least 8nF) at the FLTA and FLTB pins. See the detailed output transient response in the Typical Performance Characteristics section. When the RF input has AM content, residual ripple may be present at the output depending upon the low frequency content of the modulated RF signal. This ripple can be reduced with a larger filtering capacitor at the expense of a slower transient response. Since the output buffer amplifier of the LTC5583 is capable of driving an arbitrary capacitive load, the residual ripple can be further filtered at the output with a series resistor RSS and a large shunt capacitor CLOAD (see Figure 7). This lowpass filter also reduces the output noise by limiting the output noise bandwidth. When this RC network is designed properly, a fast output transient response can be maintained with reduced residual ripple. For example, we can estimate CLOAD with an output voltage swing of 1.7V at 2140MHz. In order to not allow the maximum 5mA sourcing current to limit the fall time (about 5μs), the maximum value of CLOAD can be chosen as follows: CLOAD ≤ 5mA • Allowable Additional Time/1.7V = 5mA • 0.25μs/1.7V = 735pF Once CLOAD is determined, RSS can be chosen properly to form an RC low-pass filter with a corner frequency of 1/[2π • (RSS + 50) • CLOAD]. In general, the rise time of the LTC5583 is much shorter than the fall time. However, when the output RC filter is used, the rise time may be dominated by the time constant of this filter. Accordingly, the rise time becomes very similar to the fall time. Although the maximum sinking capability of the LTC5583 is 5mA, it is recommended that the output load resistance should be greater than 1.2k in order to achieve the full output voltage swing. LTC5583 VCC 50Ω INPUT VOA OR VOB RSS VOUT CLOAD 5583 F07 Figure 7. Simplified Circuit Schematic of the RMS Power Detector Output Interface 5583fa 21 LTC5583 APPLICATIONS INFORMATION Temperature Compensation of Logarithmic Intercept The simplified interface schematics of the intercept temperature compensation are shown in Figure 8 and Figure 9. The adjustment of the output voltage can be described by the following equation with respect to the ambient temperature: where TC1 and TC2 are the first order and second order temperature compensation coefficients, respectively; TA is the actual ambient temperature; and tNOM is the reference room temperature 25°C; detV1 and detV2 are the output voltage variation when RT1 and RT2 are not set to zero. ΔVOUT = TC1 • (TA – tNOM) + TC2 • (TA – tNOM)2 + detV1 + detV2 LTC5583 VCC RP1 OR RP2 OPEN OR SHORT 22.2k 5583 F08 Figure 8. Simplified Interface Circuit Schematic of the Polarity Pins RP1 and RP2 LTC5583 VCC 250k RT1 OR RT2 5583 F09 Figure 9. Simplified Interface Circuit Schematic of the Control Pins RT1 and RT2 5583fa 22 LTC5583 APPLICATIONS INFORMATION The temperature coefficients TC1 and TC2 are shown as functions of the tuning resistors RT1 and RT2 in Figure 10 and Figure 11. 1.6 40 TC1 1.2 30 20 RP1 = 0 0.4 10 detV1 0 0 –0.4 detV1 RP1 = 0PEN –10 –0.8 –20 –1.2 –1.6 detV1 (mV) TC1 (mV/°C) 0.8 –30 TC1 5 10 15 20 25 RT1 (kΩ) –40 35 30 5583 F10 Figure 10. First Order Temperature Compensation Coefficient TC1 vs External RT1 Value 16 TC2 12 RP2 = OPEN RP2 RT2 (kΩ) 450 Open 11.5 0 1.13 880 Open 11.5 0 1.13 2140 Open 9.76 0 1.10 Open 8.87 0 1.21 3600 Open 10.2 0 1.65 150 5800 Open 10.0 0 1.47 –50 –8 –100 –12 –16 RT1 (kΩ) 2700 0 detV2 RP2 = 0 RP1 200 50 0 –4 Frequency (MHz) 100 detV2 4 Table 2. Suggested RP and RT Values for Optimal Temperature Performance vs RF Frequency detV2 (mV) TC2 (μV/°C2) 8 When pins RT1 and RT2 are shorted to ground, the temperature compensation circuit is disabled automatically. Polarity of the temperature coefficient TC1 (or TC2), can be selected by either shorting the RP1 pin (or RP2 pin) to ground or leaving it open, while the coefficients’ values can be controlled by external resistors RT1 and RT2 independently, according to Figures 10 and 11. At a given RF frequency, the polarities and optimal values of TC1 and TC2 can be chosen to ensure a stable output over the operating temperature range. Table 2 lists the suggested RP1, RP2, RT1 and RT2 values at various RF frequencies for the best output performance over temperature. –150 TC2 0 1 2 3 4 5 6 RT2 (kΩ) 7 8 9 –200 10 5583 F11 Figure 11. Second Order Temperature Compensation Coefficient TC2 vs External RT2 Value 5583fa 23 LTC5583 APPLICATIONS INFORMATION Envelope Detector Output: ENVA, ENVB Enable: EN Each envelope detector output linearly follows the instantaneous input power level, tracking the input signal’s RF envelope. ENVA and ENVB also indicate the peak-to-average power ratio (crest factor). Thus, reading both VOA and ENVA provides the average power, peak-to-average power ratio, peak power, and RF envelope of the input signal to Channel A. Reading VOB and ENVB provides the same information for Channel B. A simplified schematic of the EN pin interface is shown in Figure 13. The enable voltage necessary to turn on the LTC5583 is 2V. To disable or turn off the chip, set this voltage below 0.3V. It is important that the voltage applied to the EN pin should never exceed VCC by more than 0.3V. Otherwise, the supply current may be sourced through the upper ESD protection diode connected at the EN pin. Under no circumstances should voltage be applied to the EN pin before the supply pins (VCCA , VCCB, VCCR, VCCN). If this occurs, damage to the IC may result. LTC5583 VCC ENVA OR ENVB 5583 F12 Figure 12. Simplified Schematic of the ENVA and ENVB Pin LTC5583 VCC EN 49k 49k 5583 F13 Figure 13. Simplified Schematic of the Enable Pin 5583fa 24 LTC5583 APPLICATIONS INFORMATION Difference Output: VODF This voltage is equal to the difference of the two channels’ output voltages, plus a DC offset: VODF = (VOA – VOB) + VOS if INV voltage < 1V. A simplified schematic of the VOS pin interface is shown in Figure 16. The output range of VODF is from 50mV to VCC – 50mV; it cannot go below 50mV. If VOA – VOB is negative (for INV = low), a positive offset voltage VOS is needed. Similarly, if VOB – VOA is negative (for INV = high), a positive offset voltage VOS is needed. VODF = (VOB – VOA) + VOS if INV voltage > 2V. LTC5583 VCC A simplified schematic of the VODF interface is shown in Figure 14. The low 5Ω output impedance at this pin is due to internal feedback circuitry. VOS 30k * LTC5583 * VOA IF INV = LOW VOB IF INV = HIGH 15k VCC – 5583 F16 VODF + Figure 16. Simplified Schematic of the VOS Pin Supply Voltage Ramping 5583 F14 Figure 14. Simplified Schematic of the VODF Pin Figure 15 shows a simplified schematic of the INV pin interface. INV determines the sign of the difference function at the VODF output. LTC5583 VCC INV Fast ramping of the supply voltage can cause a current glitch in the internal ESD protection circuits. Depending on the supply inductance, this could result in a supply voltage overshoot at initial turn-on that exceeds the maximum rating. A supply voltage ramp time of greater than 1ms is recommended. In case this voltage ramp time is not controllable, a small (i.e. 1Ω) series resistor can be inserted between VCC pin and the supply voltage source to mitigate the problem and protect the IC. The R1 shown in Figures 1 and 2 serves this purpose. 10k 5583 F15 Figure 15. Simplified Schematic of the INV Pin 5583fa 25 LTC5583 PACKAGE DESCRIPTION UF Package 24-Lead Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1697) 0.70 ±0.05 4.50 ± 0.05 2.45 ± 0.05 3.10 ± 0.05 (4 SIDES) PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 ± 0.10 (4 SIDES) BOTTOM VIEW—EXPOSED PAD R = 0.115 TYP 0.75 ± 0.05 PIN 1 NOTCH R = 0.20 TYP OR 0.35 × 45° CHAMFER 23 24 PIN 1 TOP MARK (NOTE 6) 0.40 ± 0.10 1 2 2.45 ± 0.10 (4-SIDES) (UF24) QFN 0105 0.200 REF 0.00 – 0.05 0.25 ± 0.05 0.50 BSC NOTE: 1. DRAWING PROPOSED TO BE MADE A JEDEC PACKAGE OUTLINE MO-220 VARIATION (WGGD-X)—TO BE APPROVED 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE, IF PRESENT 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 5583fa 26 LTC5583 REVISION HISTORY REV DATE DESCRIPTION PAGE NUMBER A 12/10 Revised the maximum Shutdown Current value in the Electrical Characteristics section. 5 5583fa Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 27 LTC5583 TYPICAL APPLICATION VSWR Monitor Tx PA DIRECTIONAL COUPLER ANTENNA OUTA LTC5583 INA INB RMS DETECT ENVELOPE DETECT RMS DETECT ENVELOPE DETECT VSWR DIFFERENCE AMPLIFIER OUTB 5583 TA01 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS Infrastructure LT5527 400MHz to 3.7GHz, 5V Downconverting Mixer 2.3dB Gain, 23.5dBm IIP3 and 12.5dB NF at 1900MHz, 5V/78mA Supply LT5557 400MHz to 3.8GHz, 3.3V Downconverting Mixer 2.9dB Gain, 24.7dBm IIP3 and 11.7dB NF at 1950MHz, 3.3V/82mA Supply LTC6400-X 300MHz Low Distortion IF Amp/ADC Driver Fixed Gain of 8dB, 14dB, 20dB and 26dB; >36dBm OIP3 at 300MHz, Differential I/O LTC6401-X 140MHz Low Distortion IF Amp/ADC Driver Fixed Gain of 8dB, 14dB, 20dB and 26dB; >40dBm OIP3 at 140MHz, Differential I/O LTC6416 2GHz 16-Bit ADC Buffer 40.25dBm OIP3 to 300MHz, Programmable Fast Recovery Output Clamping LTC6412 31dB Linear Analog VGA 35dBm OIP3 at 240MHz, Continuous Gain Range –14dB to 17dB LT5554 Ultralow Distort IF Digital VGA 48dBm OIP3 at 200MHz, 2dB to 18dB Gain Range, 0.125dB Gain Steps LT5575 700MHz to 2.7GHz Direct Conversion I/Q Demodulator Integrated Baluns, 28dBm IIP3, 13dBm P1dB, 0.03dB I/Q Amplitude Match, 0.4° Phase Match LT5578 400MHz to 2.7GHz Upconverting Mixer 27dBm OIP3 at 900MHz, 24.2dBm at 1.95GHz, Integrated RF Transformer LT5579 1.5GHz to 3.8GHz Upconverting Mixer 27.3dBm OIP3 at 2.14GHz, NF = 9.9dB, 3.3V Supply, Single-Ended LO and RF Ports LTC5598 5MHz to 1.6GHz I/Q Modulator 27.7dBm OIP3 at 140MHz, 22.9dBm at 900MHz, –161.2dBm/Hz Noise Floor LTC5588-1 200MHz to 6GHz I/Q Modulator with Ultra-High OIP3 31dBm Uncalibrated OIP3, Single-Pin Calibration to Optimize OIP3 to 35dBm, –158dBm/Hz Noise Floor, 3.3V Supply RF Power Detectors LT5534 50MHz to 3GHz Log RF Power Detector with 60dB Dynamic Range ±1dB Output Variation over Temperature, 38ns Response Time, Log Linear Response LT5537 Wide Dynamic Range Log RF/IF Detector Low Frequency to 1GHz, 83dB Log Linear Dynamic Range LT5581 6GHz Low Power RMS Detector 40dB Dynamic Range, ±1dB Accuracy Over Temperature, 1.5mA Supply Current LTC5582 10GHz RMS Power Detector 57dB Dynamic Range, ±1dB Accuracy Over Temperature LTC2208 16-Bit, 130Msps ADC 78dBFS Noise Floor, >83dB SFDR at 250MHz LTC2262-14 14-Bit, 150Msps ADC Ultralow Power 72.8dB SNR, 88dB SFDR, 149mW Power Consumption LTC2242-12 12-Bit, 250Msps ADC 65.4dB SNR, 78dB SFDR, 740mW Power Consumption ADCs 5583fa 28 Linear Technology Corporation LT 1210 REV A • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2010