LTC6405CMS8E-TRPBF

LTC6405 2.7GHz, 5V, Low Noise, Rail-to-Rail Input Differential Amplifier/Driver FEATURES n n n DESCRIPTION The LTC®6405 is a very low noise, low distortion, fully differential input/output amplifier optimized for 5V, single supply operation. The LTC6405 input common mode range is rail-to-rail, while the output common mode voltage is independently adjustable by applying a voltage on the VOCM pin. This makes the LTC6405 ideal for level shifting signals with a wide common mode range for driving 12-bit to 16-bit single supply, differential input ADCs. A 2.7GHz gain-bandwidth product results in 65dB linearity for 50MHz input signals. The LTC6405 is unity gain stable and the closed-loop bandwidth extends from DC to 800MHz. The output voltage swing extends from near-ground to 4V, to be compatible with a wide range of ADC converter input requirements. The LTC6405 draws only 18mA, and has a hardware shutdown feature which reduces current consumption to 400μA. The LTC6405 is available in a compact 3mm × 3mm 16-pin leadless QFN package, as well as an 8-lead MSOP package, and operates over a –40°C to 85°C temperature range. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n n n n n n n n Low Noise: 1.6nV/√Hz RTI Low Power: 18mA at 5V Low Distortion (HD2/HD3): –82dBc/–65dBc at 50MHz, 2VP-P –97dBc/–91dBc at 25MHz, 2VP-P Rail-to-Rail Differential Input 4.5V to 5.5V Supply Voltage Range Fully Differential Input and Output Adjustable Output Common Mode Voltage 800MHz –3dB Bandwidth with AV = 1 Gain-Bandwidth Product: 2.7GHz Low Power Shutdown Available in 8-Lead MSOP and 16-Lead 3mm × 3mm × 0.75mm QFN Packages APPLICATIONS n n n n n Differential Input ADC Driver Single-Ended to Differential Conversion Level-Shifting Ground-Referenced Signals Level-Shifting VCC-Referenced Signals High-Linearity Direct Conversion Receivers TYPICAL APPLICATION Single-Ended Input to Differential Output with Common Mode Level Shifting 2VP-P 0V VS 50Ω 196Ω 4 INPUT VOLTAGE NOISE DENSITY (nV/ Hz) 1.8pF 200Ω 5V 0.1μF 1VP-P VOCM 0.01μF Input Noise Density vs Input Common Mode Voltage VS = 5V NOISE MEASURED AT f = 1MHz 4 INPUT CURRENT NOISE DENSITY (pA/ Hz) 3 in 2 en 1 3 61.9Ω SIGNAL GENERATOR 2 + LTC6405UD 2.5V 1 – 1VP-P 200Ω 1.8pF 6405 TA01 2.5V 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) 5 0 221Ω 6405 TA01b 6405fa 1 LTC6405 ABSOLUTE MAXIMUM RATINGS (Note 1) Total Supply Voltage (V+ to V–) ................................5.5V Input Current (+IN, –IN, VOCM, SHDN, VTIP) (Note 2) ............±10mA Output Short-Circuit Duration (Note 3) ............ Indefinite Operating Temperature Range (Note 4) ............................................... –40°C to 85°C Specified Temperature Range (Note 5) LTC6405I.............................................. –40°C to 85°C LTC6405C ................................................ 0°C to 70°C Junction Temperature ........................................... 150°C Storage Temperature Range................... –65°C to 150°C PIN CONFIGURATION TOP VIEW –OUTF 12 V– 17 11 V+ 10 V+ 9 5 VTIP 6 –IN 7 +OUT 8 +OUTF V– –OUT +IN NC TOP VIEW –IN 1 VOCM 2 V+ 3 +OUT 4 9 8 7 6 5 +IN SHDN V– –OUT SHDN V+ V– VOCM 1 2 3 4 MS8E PACKAGE 8-LEAD PLASTIC MSOP TJMAX = 150°C, θJA = 40°C/W, θJC = 10°C/W EXPOSED PAD (PIN 9) IS V –, MUST BE SOLDERED TO PCB 16 15 14 13 UD PACKAGE 16-LEAD (3mm × 3mm) PLASTIC QFN TJMAX = 150°C, θJA = 68°C/W, θJC = 4.2°C/W EXPOSED PAD (PIN 17) IS V–, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH LTC6405CMS8E#PBF LTC6405IMS8E#PBF LTC6405CUD#PBF LTC6405IUD#PBF TAPE AND REEL LTC6405CMS8E#TRPBF LTC6405IMS8E#TRPBF LTC6405CUD#TRPBF LTC6405IUD#TRPBF PART MARKING* LTDKN LTDKN LDKP LDKP PACKAGE DESCRIPTION 8-Lead Plastic MSOP 8-Lead Plastic MSOP 16-Lead (3mm × 3mm) Plastic QFN 16-Lead (3mm × 3mm) Plastic QFN SPECIFIED TEMPERATURE RANGE 0°C to 70°C –40°C to 85°C 0°C to 70°C –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ This product is only offered in trays. For more information go to: http://www.linear.com/packaging/ 6405fa 2 LTC6405 DC ELECTRICAL CHARACTERISTICS SYMBOL VOSDIFF PARAMETER Differential Offset Voltage (Input Referred) The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. V+ = 5V, V– = 0V, VCM = VOCM = VICM = 2.5V, VSHDN = open, circuit component values in Figure 1 used, unless otherwise noted. VS is defined as (V+ – V–). VOUTCM is defined as (V+OUT + V–OUT)/2. VICM is defined as (V+IN + V–IN)/2. VOUTDIFF is defined as (V+OUT – V–OUT). CONDITIONS VICM = 5V (Note 12) VICM = 2.5V VICM = 0V (Note 12) VICM = 5V (Note 12) VICM = 2.5V VICM = 0V (Note 12) VICM = 5V VICM = 2.5V VICM = 0V VICM = 5V VICM = 2.5V VICM = 0V Common Mode Differential Mode Differential f = 1MHz, Not Including RI/RF Noise f = 1MHz, Not Including RI/RF Noise f = 1MHz Op-Amp Inputs VICM from 0V to 5V VOCM from 0.5V to 3.9V VS = 4.5V to 5.5V VS = 4.5V to 5.5V VOCM from 0.5V to 3.9V VOCM from 0.5V to 3.9V ΔVOUTDIFF = 2V Single-Ended Input Differential Input l l l l l l l l l l l l l l l l l l l l MIN TYP ±1 ±0.5 ±1 1.5 1 3 8 –7 –14 ±0.5 ±0.5 ±0.5 230 3.5 1 1.6 2.4 9.5 MAX ±7 ±3.5 ±7 UNITS mV mV mV μV/°C μV/°C μV/°C μA μA μA μA μA μA kΩ kΩ pF nV/√Hz pA/√Hz nV/√Hz ΔVOSDIFF/ΔT Differential Offset Voltage Drift (Input Referred) IB Input Bias Current (Note 6) –24 IOS Input Offset Current (Note 6) l ±4 RIN CIN en in enVOCM VICMR (Note 7) CMRRI (Note 8) CMRRIO (Note 8) PSRR (Note 9) PSRRCM (Note 9) GCM ΔGCM BAL Input Resistance Input Capacitance Differential Input Referred Noise Voltage Density Input Noise Current Density Input Referred Common Mode Output Noise Voltage Density Input Signal Common Mode Range Input Common Mode Rejection Ratio (Input Referred) ΔVICM/ΔVOSDIFF Output Common Mode Rejection Ratio (Input Referred) ΔVOCM/ΔVOSDIFF Differential Power Supply Rejection (ΔVS/ΔVOSDIFF) Output Common Mode Power Supply Rejection (ΔVS/ΔVOSCM) Common Mode Gain (ΔVOUTCM/ΔVOCM) Common Mode Gain Error 100 • (GCM – 1) Output Balance (ΔVOUTCM/ΔVOUTDIFF) V– 50 50 50 55 75 75 75 70 1 ±0.25 –60 –65 ±6 20 0.5 13 2.35 3.9 3.85 19 2.5 4 3.95 0.3 0.42 ±60 V+ V dB dB dB dB V/V ±0.8 –40 –40 ±15 3.9 25 2.65 % dB dB mV μV/°C V kΩ V V V V V mA VOSCM ΔVOSCM/ΔT VOUTCMR (Note 7) RINVOCM VOCM VOUT Common Mode Offset Voltage (VOUTCM – VOCM) Common Mode Offset Voltage Drift Output Signal Common Mode Range (Voltage Range for the VOCM Pin) Input Resistance, VOCM Pin Self-Biased Voltage at the VOCM Pin Output Voltage, High, +OUT/–OUT Pins Output Voltage, Low, +OUT/–OUT Pins VOCM = Open IL = 0 IL = –5mA IL = 0 IL = 5mA l l l l l l 0.4 0.54 ISC Output Short-Circuit Current, +OUT/–OUT Pins (Note 10) ±40 6405fa 3 LTC6405 DC ELECTRICAL CHARACTERISTICS SYMBOL AVOL VS IS ISHDN RSHDN VIL VIH tON tOFF PARAMETER Large-Signal Open Loop Voltage Gain Supply Voltage Range Supply Current Supply Current in Shutdown SHDN Pull-Up Resistor SHDN Input Logic Low SHDN Input Logic High Turn-On Time Turn-Off Time VSHDN = 0V VSHDN = 0V to 0.5V l l l l l l The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. V+ = 5V, V– = 0V, VCM = VOCM = VICM = 2.5V, VSHDN = open, circuit component values in Figure 1 used, unless otherwise noted. VS is defined as (V+ – V–). VOUTCM is defined as (V+OUT + V–OUT)/2. VICM is defined as (V+IN + V–IN)/2. VOUTDIFF is defined as (V+OUT – V–OUT). CONDITIONS MIN 4.5 18 0.4 30 1.25 50 1.8 2 200 50 2.55 TYP 90 5.5 23 1 70 MAX UNITS dB V mA mA kΩ V V ns ns AC ELECTRICAL CHARACTERISTICS SYMBOL SR GBW f–3dB PARAMETER Slew Rate Gain-Bandwidth Product –3dB Frequency (See Figure 2) 50MHz Distortion Differential Input, VOUTDIFF = 2VP-P (Note 13) The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. V+ = 5V, V– = 0V, VCM = VOCM = VICM = 2.5V, VSHDN = open, RLOAD = 400Ω, circuit component values in Figure 2 used, unless otherwise noted. VS is defined as (V+ – V–). VICM is defined as (V+IN + V–IN)/2. VOUTDIFF is defined as (V+OUT – V–OUT). CONDITIONS Differential Output fTEST = 27MHz QFN Package MSOP Package VOCM = 2.5V, VS = 5V 2nd Harmonic 3rd Harmonic VOCM = 2.5V, VS = 5V, RLOAD = 800Ω 2nd Harmonic 3rd Harmonic VOCM = 2.5V, VS = 5V, RLOAD = 800Ω, RI = RF = 499Ω 2nd Harmonic 3rd Harmonic 50MHz Distortion Single-Ended Input, VOUTDIFF = 2VP-P (Note 13) 3rd-Order IMD at 49.5MHz, 50.5MHz Equivalent OIP3 at 50MHz (Note 11) VOCM = 2.5V, VS = 5V, RLOAD = 800Ω, RI = RF = 499Ω 2nd Harmonic 3rd Harmonic VOUTDIFF = 2VP-P Envelope, RLOAD = 800Ω RLOAD = 800Ω VOUTDIFF = 2V Step 1% Settling 0.1% Settling Shunt-Terminated to 50Ω, RS = 50Ω ZIN = 200Ω (RI = 100Ω, RF = 300Ω) 500 400 MIN TYP 690 2.7 800 750 –80 –64 –82 –66 MAX UNITS V/μS GHz MHz MHz dBc dBc dBc dBc l –53 –82 –64 dBc dBc –72 –77 –63 35.5 6 11 14.4 7.5 dBc dBc dBc dBm ns ns dB dB tS Settling Time NF Noise Figure at 50MHz 6405fa 4 LTC6405 ELECTRICAL CHARACTERISTICS 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: Input pins (+IN, –IN, VOCM, SHDN and VTIP) are protected by steering diodes to either supply. If the inputs should exceed either supply voltage, the input current should be limited to less than 10mA. In addition, the inputs +IN, –IN are protected by a pair of back-to-back diodes. If the differential input voltage exceeds 1.4V, the input current should be limited to less than 10mA. Note 3: A heat sink may be required to keep the junction temperature below the Absolute Maximum Rating when the output is shorted indefinitely. Note 4: The LTC6405C/LTC6405I are guaranteed functional over the operating temperature range –40°C to 85°C. Note 5: The LTC6405C is guaranteed to meet specified performance from 0°C to 70°C. The LTC6405C is designed, characterized, and expected to meet specified performance from –40°C to 85°C but is not tested or QA sampled at these temperatures. The LTC6405I is guaranteed to meet specified performance from –40°C to 85°C. Note 6: Input bias current is defined as the average of the input currents flowing into the inputs (–IN, and +IN). Input Offset current is defined as the difference between the input currents (IOS = IB+ – IB–). Note 7: Input common mode range is tested using the test circuit of Figure 1 by taking 3 measurements of differential gain with a ±1VDC differential output with VICM = 0V; VICM = 2.5V; VICM = 5V, verifying that the differential gain has not deviated from the VICM = 2.5V case by more than 0.5%, and that the common mode offset (VOSCM) has not deviated from the common mode offset at VICM = 2.5V by more than ±35mV. The voltage range for the output common mode range is tested using the test circuit of Figure 1 by applying a voltage on the VOCM pin and testing at both VOCM = 2.5V and at the Electrical Characteristics table limits to verify that the common mode offset (VOSCM) has not deviated by more than ±20mV from the VOCM = 2.5V case. Note 8: Input CMRR is defined as the ratio of the change in the input common mode voltage at the pins +IN or –IN to the change in differential input referred voltage offset. Output CMRR is defined as the ratio of the change in the voltage at the VOCM pin to the change in differential input referred voltage offset. This specification is strongly dependent on feedback ratio matching between the two outputs and their respective inputs, and it is difficult to measure actual amplifier performance. (See the “Effects of Resistor Pair Mismatch” in the Applications Information section of this data sheet.) For a better indicator of actual amplifier performance independent of feedback component matching, refer to the PSRR specification. Note 9: Differential Power Supply Rejection (PSRR) is defined as the ratio of the change in supply voltage to the change in differential input referred voltage offset. Common mode power supply rejection (PSRRCM) is defined as the ratio of the change in supply voltage to the change in the common mode offset, VOUTCM – VOCM. Note 10: Extended operation with the output shorted may cause the junction temperature to exceed the 150°C limit. Note 11: Because the LTC6405 is a feedback amplifier with low output impedance, a resistive load is not required when driving an ADC. Therefore, typical output power can be very small in many applications. In order to compare the LTC6405 with “RF style” amplifiers that require 50Ω load, the output voltage swing is converted to dBm as if the outputs were driving a 50Ω load. For example, 2VP-P output swing is equal to 10dBm using this convention. Note 12: Includes offset/drift induced by feedback resistors mismatch. See the Applications Information section for more details. Note 13: QFN package only—refer to datasheet curves for MSOP package numbers. 6405fa 5 LTC6405 TYPICAL PERFORMANCE CHARACTERISTICS Differential Input Referred Offset Voltage vs Temperature 1.0 0.8 0.6 DIFFERENTIAL VOS (mV) 0.4 0.2 0 VS = 5V VOCM = 2.5V VICM = 2.5V RI = RF = 200Ω FIVE REPRESENTATIVE UNITS 1.0 0.8 0.6 DIFFERENTIAL VOS (V) 0.4 0.2 0 Differential Input Referred Offset Voltage vs Input Common Mode Voltage COMMON MODE OFFSET VOLTAGE (mV) VS = 5V 0.1% FEEDBACK NETWORK VOCM = 2.5V RESISTORS REPRESENTRI = RF = 200Ω ATIVE UNIT 9 Common Mode Offset Voltage vs Temperature VS = 5V VOCM = 2.5V 8 VICM = 2.5V FIVE REPRESENTATIVE UNITS 7 6 5 4 3 2 –50 –0.2 –0.2 TA = – 40°C TA = 0°C TA = 25°C TA = 70°C TA = 85°C 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) 6405 G02 –0.4 –0.6 –0.8 –0.4 –0.6 –0.8 –1.0 –50 –1.0 –25 25 50 0 TEMPERATURE (°C) 75 100 6405 G01 5 –25 25 50 0 TEMPERATURE (°C) 75 100 6405 G03 Supply Current vs Supply Voltage 20 TOTAL SUPPLY CURRENT (mA) VSHDN = OPEN TOTAL SUPPLY CURRENT (mA) TA = –40°C TA = 0°C TA = 25°C TA = 70°C TA = 85°C 20 Supply Current vs SHDN Voltage VS = 5V SHUTDOWN SUPPLY CURRENT (μA) 600 500 400 300 200 100 0 Shutdown Supply Current vs Supply Voltage VSHDN = V – TA = – 40°C TA = 0°C TA = 25°C TA = 70°C TA = 85°C 15 15 10 10 5 5 0 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 SUPPLY VOLTAGE (V) 6405 G04 TA = – 40°C TA = 0°C TA = 25°C TA = 70°C TA = 85°C 0 0.5 1 1.5 2 2.5 3 3.5 SHDN VOLTAGE (V) 4 4.5 5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 SUPPLY VOLTAGE (V) 6405 G06 6405 G05 6405fa 6 LTC6405 TYPICAL PERFORMANCE CHARACTERISTICS Input Noise Density vs Frequency 100 INPUT VOLTAGE NOISE DENSITY (nV/ Hz) INPUT VOLTAGE NOISE DENSITY (nV/ Hz) VS = 5V VICM = 2.5V 100 INPUT CURRENT NOISE DENSITY (pA/ Hz) 4 Input Noise Density vs Input Common Mode Voltage VS = 5V NOISE MEASURED AT f = 1MHz 4 INPUT CURRENT NOISE DENSITY (pA/ Hz) 720 700 SLEW RATE (V/μs) 680 660 640 620 Differential Slew Rate vs Temperature VS = 5V 3 in 2 en 1 3 10 10 2 in en 1 100 1k 10k 100k FREQUENCY (Hz) 1M 1 10M 6405 G07 1 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) 5 0 600 –50 –25 25 50 0 TEMPERATURE (°C) 75 100 6405 G09 6405 G08 Differential Output Impedance vs Frequency 1000 VS = 5V RI = RF = 200 90 80 70 CMRR (dB) 10 CMRR vs Frequency 80 70 60 PSRR (dB) 50 40 30 20 10 Differential PSRR vs Frequency VS = 5V OUTPUT IMPEDANCE (Ω) 100 60 50 40 1 0.1 0.01 1 10 100 FREQUENCY (MHz) 1000 2000 6405 G10 VS = 5V VOCM = 2.5V 30 RI = RF = 200 , CF = 1.8pF 0.1% FEEDBACK NETWORK RESISTORS 20 1 10 100 1000 2000 FREQUENCY (MHz) 6405 G11 1 10 100 FREQUENCY (MHz) 1000 2000 6405 G12 6405fa 7 LTC6405 TYPICAL PERFORMANCE CHARACTERISTICS Small Signal Step Response +OUT VOLTAGE (V) 20mV/DIV 0.2V/DIV (QFN Package) Overdriven Output Transient Response 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 6405 G14 Large Signal Step Response +OUT –OUT –OUT 6405 G13 –OUT 10ns/DIV VS = 5V RLOAD = 400 VIN = 2VP-P, DIFFERENTIAL +OUT 100ns/DIV VS = 5V VOCM = 2.5V RLOAD = 400 6405 G15 10ns/DIV VS = 5V RI = RF = 200 VOCM = VICM = 2.5V CF = 1.8pF RLOAD = 400 CL = 0pF 0 TO GROUND PER OUTPUT Frequency Response vs Closed Loop Gain 50 40 30 20 GAIN (dB) 10 0 –10 –20 –30 VS = 5V –40 VOCM = VICM = 2.5V RLOAD = 400 –50 1 10 100 FREQUENCY (MHz) AV (V/V) RI ( ) 1 2 5 10 20 100 200 200 200 200 200 200 RF ( ) 200 400 1k 2k 4k 20k AV = 2 AV = 1 AV = 100 AV = 20 AV = 10 AV = 5 GAIN (dB) 30 20 10 0 –10 –20 Frequency Response vs Load Capacitance CL = 0pF CL = 2pF CL = 3pF CL= 4.7pF CL = 10pF GAIN (dB) 10 5 0 –5 –10 –15 –20 –25 Frequency Response vs Input Common Mode Voltage 1000 2000 CF (pF) 1.8 1.5 0.6 0.2 0 0 6405 G16 VS = 5V –30 VOCM = VICM = 2.5V RLOAD = 400 –40 RI = RF = 200 , CF = 1.8pF CAPACITOR VALUES ARE FROM EACH –50 OUTPUT TO GROUND. NO SERIES RESISTORS ARE USED. –60 1 10 100 1000 2000 FREQUENCY (MHz) 6405 G17 VICM = 0V VICM = 0.5V VICM = 1.25V VICM = 2.5V VICM = 4V VICM = 5V VS = 5V VOCM = 2.5V –35 RLOAD = 400 RI = RF = 200 , CF = 1.8pF –40 1 10 100 FREQUENCY (MHz) –30 1000 2000 6405 G18 6405fa 8 LTC6405 TYPICAL PERFORMANCE CHARACTERISTICS Harmonic Distortion vs Frequency –30 –40 –50 DISTORTION (dBc) –60 –70 –80 –90 VS = 5V VOCM = VICM = 2.5V VTIP = OPEN (2.8V) RLOAD = 800 , VOUTDIFF = 2VP-P DIFFERENTIAL INPUTS HD3 RI = RF = 499 HD3 RI = RF = 200 HD2 RI = RF = 200 100 6405 G19 (QFN Package) Harmonic Distortion vs Input Amplitude –40 VS = 5V VOCM = VICM = 2.5V –50 VTIP = OPEN (2.8V) fIN = 50MHz RLOAD = 800 –60 RI = RF = 200 DIFFERENTIAL INPUTS –70 –80 HD2 –90 –100 –4 –2 (0.4VP-P) HD3 Harmonic Distortion vs Input Common Mode Voltage –40 RLOAD = 800 VS = 5V VOCM = 2.5V VOUTDIFF = 2VP-P –50 VTIP = OPEN (2.8V) DIFFERENTIAL INPUTS fIN = 50MHz RI = RF = 200 HD3 –60 –70 –80 –90 –100 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) 5 6405 G20 DISTORTION (dBc) RI = RF = 499 HD2 RI = RF = 499 –100 –110 –120 1 HD2 RI = RF = 499 RI = RF = 200 10 FREQUENCY (MHz) DISTORTION (dBc) 0 2 4 6 INPUT AMPLITUDE (dBm) 8 10 (2VP-P) 6405 G21 Harmonic Distortion vs Frequency –30 VS = 5V RLOAD = 800 –40 VOCM = VICM = 2.5V VOUTDIFF = 2VP-P SINGLE-ENDED INPUT VTIP = 2.35V –50 DISTORTION (dBc) DISTORTION (dBc) –60 –70 –80 –90 –100 –110 1 HD2, RI = RF = 200 HD2, RI = RF = 499 HD3, RI = RF = 200 HD3, RI = RF = 499 10 FREQUENCY (MHz) 100 6405 G22 Harmonic Distortion vs Input Common Mode Voltage –40 –50 –60 –70 HD3 –80 –90 –100 VS = 5V VOCM = 2.5V VTIP = 2.35V fIN = 50MHz RLOAD = 800 RI = RF = 499 VOUTDIFF = 2VP-P SINGLE-ENDED INPUT 5 DISTORTION (dBc) HD2 –40 Harmonic Distortion vs Input Amplitude VS = 5V VOCM = VICM = 2.5V –50 VTIP = 2.35V fIN = 50MHz RLOAD = 800 –60 RI = RF = 499 SINGLE-ENDED INPUT –70 –80 –90 –100 –4 –2 (0.4VP-P) HD2 HD3 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) 0 2 4 6 INPUT AMPLITUDE (dBm) 8 10 (2VP-P) 6405 G24 6405 G23 Intermodulation Distortion vs Frequency –30 VS = 5V –40 VOCM = VICM = 2.5V VTIP = OPEN (2.8V) RLOAD = 800 –50 RI = RF = 200 2 TONES, 1MHz TONE SPACING, –60 2VP-P COMPOSITE DIFFERENTIAL INPUTS –70 –80 –90 –100 –110 1 10 FREQUENCY (MHz) 100 6405 G25 Intermodulation Distortion vs Input Common Mode Voltage –40 –50 THIRD ORDER IMD (dBc) –60 VS = 5V VOCM = 2.5V VTIP = OPEN (2.8V) –80 fIN = 50MHz RLOAD = 800 RI = RF = 200 –90 2 TONES,1MHz TONE SPACING, 2VP-P COMPOSITE DIFFERENTIAL INPUTS –100 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 INPUT COMMON MODE VOLTAGE (V) –70 THIRD ORDER IMD (dBc) –40 Intermodulation Distortion vs Input Amplitude VS = 5V VOCM = VICM = 2.5V –50 VTIP = OPEN (2.8V) fIN = 50MHz RLOAD = 800 –60 RI = RF = 200 2 TONES, 1MHz TONE SPACING DIFFERENTIAL INPUTS –70 –80 –90 –100 –4 –2 (0.4VP-P) THIRD ORDER IMD (dBc) 5 0 2 4 6 INPUT AMPLITUDE (dBm) 8 10 (2VP-P) 6405 G27 6405 G26 6405fa 9 LTC6405 TYPICAL PERFORMANCE CHARACTERISTICS Frequency Response vs Load Capacitance 30 20 10 DISTORTION (dBc) GAIN (dB) 0 –10 –20 CL = 0pF CL = 10pF –30 (MSOP Package) Harmonic Distortion vs Input Amplitude –40 VS = 5V VOCM = VICM = 2.5V –50 VTIP = OPEN (2.8V) fIN = 50MHz RLOAD = 800 –60 RI = RF = 300 DIFFERENTIAL INPUTS –70 HD3 –80 –90 –100 –4 –2 (0.4VP-P) Harmonic Distortion vs Frequency VS = 5V –40 VOCM = VICM = 2.5V VTIP = OPEN (2.8V) RLOAD = 800 –50 RI = RF = 300 = 2VP-P V –60 OUTDIFF DIFFERENTIAL INPUTS –70 –80 HD3 –90 HD2 –100 –110 1 10 FREQUENCY (MHz) 100 6405 G29 DISTORTION (dBc) HD2 VS = 5V VOCM = VICM = 2.5V = 400 R –30 RLOAD = 300 , C = 1pF I = RF F CAPACITOR VALUES ARE FROM EACH –40 OUTPUT TO GROUND. NO SERIES RESISTORS ARE USED. –50 1 10 100 1000 2000 FREQUENCY (MHz) 6405 G28 0 2 4 6 INPUT AMPLITUDE (dBm) 8 10 (2VP-P) 6405 G30 Harmonic Distortion vs Frequency –30 VS = 5V –40 VOCM = VICM = 2.5V VTIP = OPEN (2.8V) RLOAD = 800 –50 RI = RF = 300 = 2VP-P V –60 OUTDIFF SINGLE-ENDED INPUT –70 –80 –90 HD3 –100 –110 1 10 FREQUENCY (MHz) 100 6405 G31 Harmonic Distortion vs Input Amplitude –40 VS = 5V VOCM = VICM = 2.5V –50 VTIP = OPEN (2.8V) fIN = 50MHz RLOAD = 800 –60 –70 –80 –90 –100 –4 –2 (0.4VP-P) RI = RF = 300 SINGLE-ENDED INPUT HD2 DISTORTION (dBc) DISTORTION (dBc) HD3 HD2 0 2 4 6 INPUT AMPLITUDE (dBm) 8 10 (2VP-P) 6405 G32 6405fa 10 LTC6405 PIN FUNCTIONS (MSOP/QFN) VOCM (Pin 2/Pin 4): Output Common Mode Reference Voltage. The voltage on VOCM sets the output common mode voltage level (which is defined as the average of the voltages on the +OUT and –OUT pins). The VOCM voltage is internally set by a resistive divider between the supplies, developing a default voltage potential of 2.5V with a 5V supply. The VOCM pin can be over-driven by an external voltage capable of driving the 19kΩ Thevenin equivalent impedance presented by the pin. The VOCM pin should be bypassed with a high quality ceramic bypass capacitor of at least 0.01μF to minimize common mode noise from being , converted to differential noise by impedance mismatches both externally and internally to the IC. V+ (Pin 3/Pins 2, 10, 11): V– (Pin 6/Pins 3, 9, 12): Power Supply Pins. It is critical that close attention be paid to supply bypassing. For single supply applications, it is recommended that a high quality 0.1μF surface mount ceramic bypass capacitor be placed between V+ and V– with direct short connections. In addition, V– should be tied directly to a low impedance ground plane with minimal routing. For dual (split) power supplies, it is recommended that additional high quality, 0.1μF ceramic capacitors are used to bypass V+ to ground and V– to ground, again with minimal routing. For driving large loads (