LTC1566-1 AD | Alldatasheet

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1566-1 is a 7th order continuous time lowpass filter with 12dB of passband gain. The selectivity, linearity and dynamic range makes the LTC1566-1 suitable for filtering in data communications or data acquisition systems. The filter attenuation is 40dB at 1.5 × f CUTOFF and at least 60dB for frequencies above 10MHz. The LTC1566-1 has an input referred noise of 62µVRMS in a 2MHz bandwidth. In receiver applications where the signal levels are small, the filter features 71dB of spurious free dynamic range. With 5% accuracy of the cutoff frequency, the LTC1566-1 can be used in applications requiring pairs of matched filters, such as transceiver I and Q channels. The differential inputs and outputs provide a simple inter- face for wireless systems. The high impedance inputs are easily coupled to differential demodulators or D/A con- verters. The output DC common mode voltage and output DC offset voltage are adjustable so the signal path can be optimized for driving an A/D converter or differential modulator. Other cutoff frequencies and single-ended I/O can be provided upon request. Please contact LTC Marketing. ■ WCDMA Basestations ■ Communication Filters ■ Antialiasing Filters ■ Smoothing or Reconstruction Filters ■ Matched Filter Pairs ■ Replacement for LC Filters , LTC and LT are registered trademarks of Linear Technology Corporation. ■ 7th Order, 2.3MHz Lowpass Filter in an SO-8 ■ 62µVRMS Input Referred Noise ■ Operates on a Single 5V or a ±5V Supply ■ Differential Inputs and Outputs ■ Low Offset (3mV typical, 10mVMAX) ■ Adjustable Output Common Mode Voltage ■ 40dB Attenuation at 1.5 × fCUTOFF ■ Requires No External Components Low Noise 2.3MHz Continuous Time Lowpass Filter Frequency Response Single 5V Supply, Differential 2.3MHz Lowpass Filter LTC1566-1 OUT+ OUT– VODC IN+ IN– GND V V IN VOUT 10k 10k 0.1µF 0.1 µF 1566-1 TA01 FREQUENCY (MHz) 0.1 GAIN (dB) –10 –20 –30 –40 –50 –60 –70 –80 1000 900 800 700 600 500 400 300 200 100 1.0 10 100 1566-1 G01 DELAY (ns) DELAY GAIN

Operating Temperature Range ORDER PART NUMBER TJMAX = 125°C, θJA = 80°C/W (Note 4) Consult factory for parts specified with wider operating temperature ranges. LTC1566-1CS8 LTC1566-1IS8 ABSOLUTE AXI U RATI GSW WW U PACKAGE/ORDER I FOR ATIOUU W (Note 1) ELECTRICAL CHARACTERISTICSThe ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V (V+ = 5V, V– = 0V), RLOAD = 10k from each output to AC ground, Pin 5 connected to Pin 3, Pin 3 biased to mid supply, unless otherwise specified. PARAMETER CONDITIONS MIN TYP MAX UNITS Filter Gain, VS = 5V V IN = 0.25VP-P fIN = 20kHz to 100kHz ● 11.8 12.1 12.3 dB fIN = 1.8MHz (Gain Relative to 100kHz) ● –0.35 0 0.8 dB fIN = 2MHz (Gain Relative to 100kHz) ● –0.85 – 0.1 0.8 dB fIN = 2.3MHz (Gain Relative to 100kHz) ● –7.5 –3 –0.95 dB fIN = 3MHz (Gain Relative to 100kHz) ● –2 2 –1 7 d B fIN = 5MHz (Gain Relative to 100kHz) – 42 dB fIN = 10MHz (Gain Relative to 100kHz) – 62 dB Filter Phase, VS = ±5V V IN = 0.25VP-P fIN = 900kHz ● –165 –150 –135 deg fIN = 1.8MHz ● –330 –285 –265 deg Phase Linearity, VS = ±5V Ratio of phases: 1.8MHz/900kHz ● 1.9 1.95 2.05 Filter Gain, VS = ±5V V IN = 0.25VP-P fIN = 20kHz to 100kHz ● 11.9 12.1 12.3 dB fIN = 900kHz (Gain Relative to 100kHz) ● –0.2 0 0.2 dB fIN = 1.8MHz (Gain Relative to 100kHz) ● –0.3 0.1 0.9 dB fIN = 2MHz (Gain Relative to 100kHz) ● –0.55 0.1 0.75 dB fIN = 2.3MHz (Gain Relative to 100kHz) ● –6 –2 –0.3 dB fIN = 3MHz (Gain Relative to 100kHz) ● –2 0 –1 6 d B fIN = 5MHz (Gain Relative to 100kHz) – 41 dB fIN = 10MHz (Gain Relative to 100kHz) –61 dB Input Referred Wideband Noise Noise BW = 50kHz to 2MHz 62 µVRMS THD f IN = 100kHz, VOUT = 2VP-P (Note 2) 80 dB Filter Differential DC Swing Maximum Difference Between Pins 7 and Pin 8 V S = 5V ● ±1.3 ±1.7 V P with Pin 5, Pin 3 Biased to Mid Supply V S = ±5V ● ±2.7 ±2.9 V P Input Bias Current ● 300 600 nA Input Offset Current ±10 nA Input Resistance Common Mode, V IN = 1.5V to 3.5V 70 M Ω Differential 140 M Ω Input Capacitance 2p F Output DC Offset VS = 5V ±3 ±10 mV (Notes 3, 5) VS = ±5V ±3 ±10 mV TOP VIEW OUT+ OUT– VODC IN+ IN– GND V – S8 PACKAGE 8-LEAD PLASTIC SO S8 PART MARKING 15661 15661I

PARAMETER CONDITIONS MIN TYP MAX UNITS Output DC Offset Drift V S = 5V –160 µV/°C VS = ±5V –160 µV/°C Output DC Common Mode Voltage V S = 5V, VS = ±2.5V –80 mV Power Supply Current V S = 5V ● 24 32 mA VS = ±5V ● 25 34 mA ELECTRICAL CHARACTERISTICSThe ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = 5V (V+ = 5V, V– = 0V), RLOAD = 10k from each output to AC ground, and Pin 5 connected to Pin 3 unless otherwise specified Note 4: Thermal resistance varies depending upon the amount of PC board metal attached to the device. θJA is specified for a 3.8 square inch test board covered with 2oz copper on both sides. Note 5: Output DC offset measurements are performed by automatic test equipment approximately 0.5 seconds after application of power. TYPICAL PERFOR A CE CHARACTERISTICSUW FREQUENCY (Hz) 10k GAIN (dB) 12.4 12.0 11.6 11.2 10.8 10.4 100k 1M 5M 1566-1 G02 DELAY (µs) TA = 25°C GAIN ±5V GAIN 5V DELAY FREQUENCY (Hz) 10k GAIN (dB) 12.4 12.0 11.6 11.2 10.8 10.4 100k 1M 5M 1566-1 G03 TA = 85°C TA = –40°C TA = 25°C VIN (dbm) –25 –20 –40 –60 –80 –100 –10 0 1566-1 G07 –20 –15 –5 5 10 VOUT (dBm) 500kHz 1MHz 1.5MHz NOISE FLOOR 1dB COMPRESSION Passband Gain and Delay vs Frequency Passband Gain vs Frequency and Temperature Stopband Gain vs Frequency Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Input and output voltages expressed as peak-to-peak numbers are assumed to be fully differential. Note 3: Output DC offset is measured between Pin 8 and Pin 7 with Pin 1, Pin 2 and Pin 5 connected to Pin 3. Pin 3 biased to mid supply. Stopband Gain vs Frequency and Temperature 450k/2M Intermodulation, VS = 5V 500kHz Distortion vs Input Level, VS = 5V FREQUENCY (MHz) GAIN (dB) –10 –20 –30 –40 –50 –60 47 8 9 51 0 6 1566-1 G04 ±5V TA = 25°C FREQUENCY (MHz) GAIN (dB) –10 –20 –30 –40 –50 –60 47 8 9 51 0 6 1566-1 G05 TA = 25°C TA = –40, 85°C VS = 5V VX (dBm) –25 VOUT (dBm) –20 –40 –60 –80 –100 –20 –15 –10 –5 1566-1 G06 450k 1.55M 2.45M 3.55M NOISE FLOOR 1.1M OIP3 = 38dBm OIP2 = 74dBm VIN = VX COS(2π • 450kHz) + VX COS (2π • 2MHz)

IN+, IN– (Pins 1, 2): Input Pins. Signals can be applied to either or both input pins. The DC gain from differential inputs (Pin 1 to Pin 2) to the differential outputs (Pin 8 to Pin 7) is 4V/V. The input range is described in the Applica- tions Information section. GND (Pin 3): Ground. The ground pin is the reference voltage for the filter. This is a high impedance input, which requires an external biasing network. Biasing GND to one-half the total power supply voltage of the filter maxi- mizes the dynamic range. For single supply operation the ground pin should be bypassed with a quality 0.1 µF ceramic capacitor to Pin 4. For dual supply operation, connect Pin 3 to a high quality DC ground. A ground plane should be used. A poor ground will increase noise and distortion. Pin 3 also serves as the DC reference voltage for Pin 7. V –, V+ (Pins 4, 6): Power Supply Pins. For a single 5V supply (Pin 4 grounded) a quality 0.1µF ceramic bypass capacitor is required from the positive supply pin (Pin 6) to the negative supply pin (Pin 4). The bypass should be as close as possible to the IC. For dual supply applications (Pin 3 is grounded), bypass Pin 6 to Pin 3 and Pin 4 to Pin 3 with a quality 0.1µF ceramic capacitor. VODC (Pin 5): Output DC Offset. Pin 5 is the DC reference voltage for Pin 8. By applying a DC offset between Pin 3 and Pin 5, a DC offset will be added to the differential signal between Pin 7 and Pin 8. Like the GND pin, the VODC pin is a high impedance which requires no bias current. Care should be taken when biasing Pin 5 since noise between Pin 3 and Pin 5 will appear at the filter output unattenuated. The frequency response of Pin 5 is described in the Applications Information section. OUT – , OUT+ (Pins 7, 8): Output Pins. Pins 7 and 8 are the filter differential outputs. Each pin can drive 1kΩ or 300pF loads. The DC reference voltage of Pin 8 is the same as the voltage at Pin 5. The DC reference voltage of Pin 7 is the same as the voltage at Pin 3. TYPICAL PERFOR A CE CHARACTERISTICSUW TEMPERATURE (°C) –50 SUPPLY CURRENT (mA) 1566-1 G08 –10 30 –30 10 50 90 VS = ±5V VS = 5V FREQUENCY (Hz) CMRR (dB) 10k 100k 1M 10M 1566-1 G09 VIN = 1VP-P VS = 5V TA = 25°C FREQUENCY (Hz) PSRR (dB) 10k 100k 1M 10M 1566-1 G10 VIN = 0.2VP-P VS = 5V TA = 25°C Supply Current vs Temperature Common Mode Rejection Ratio Power Supply Rejection Ratio

Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com © LINEAR TECHNOLOGY CORPORATION 2001 LT/TP 0504 1K REV A • PRINTED IN USA RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC1560-1 1MHz/500kHz Continuous Time, Lowpass Elliptic Filter f CUTTOFF = 500kHz or 1MHz LTC1562/LTC1562-2 Universal 8th Order Active RC Filters f CUTOFF(MAX) = 150kHz (LTC1562), fCUTOFF(MAX) = 300kHz (LTC1562-2) LTC1563-2/LTC1563-3 4th Order Active RC Lowpass Filters f CUTOFF(MAX) = 256kHz LTC1565-31 650kHz Continuous Time, Linear Phase Lowpass Filter 7th Order, Differential Inputs and Outputs LTC1569-6/LTC1569-7 Self Clocked, 10th Order Linear Phase Lowpass Filters f CLK/fCUTOFF = 64/1, fCUTOFF(MAX) = 75kHz (LTC1569-6), fCLK/fCUTOFF = 32/1, fCUTOFF(MAX) = 300kHz (LTC1569-7) Wideband CDMA Base Station Receiver Block Diagram 1566-1 TA01a IN+ IN– GND OUT+ OUT– VODC LTC1566-1 50Ω 50Ω 10k 10k 0.1µF 0.1µF 0.1µF Σ°VIN VOUT MINICIRCUITS SPLITTER ZSCJ-2-2 –15V 15V LT1363 2.5V –2.5V CLOSE SWITCH S1 AND APPLY A VOLTAGE TO ALTER THE OUTPUT COMMON MODE. CLOSE SWITCH S2 AND APPLY A VOLTAGE TO ADD A DC OFFSET. CHANGE THE POWER SUPPLY VOLTAGES TO ALTER THE INPUT COMMON MODE VOLTAGE. FOR EXAMPLE, V S = 3, –2 MAKES THE EFFECTIVE INPUT COMMON MODE –0.5V BELOW MID SUPPLY. 1566-1 TA02a IN+ IN– GND OUT+ OUT– VODC LTC1566-1 0.1µF 0.1 µF VOUT 10k 10k2k 5V5V 5Mbps DATA 15k LTC1566-1 LPF ADC ADC 0°/90°RF/IF SECTION LO DSP I Q 90° 1566-1 TA03 LTC1566-1 LPF A Fixture for Evaluation with Single-Ended, Ground Referenced Test Equipment Simple Pulse Shaping Circuit for Single 5V Operation, 5Mbps 2 Level Data TYPICAL APPLICATIO SU 1566-1 TA02b 50ns/DIV 0300mV/ DIV