LTC1164-8_09

OBSOLETE: FOR INFORMATION PURPOSES ONLY Contact Linear Technology for Potential Replacement LTC1164-8 Ultraselective, Low Power 8th Order Elliptic Bandpass Filter with Adjustable Gain FEATURES ■ ■ ■ ■ ■ ■ ■ DESCRIPTION The LTC®1164-8 is a monolithic ultraselective, 8th order, elliptic bandpass filter. The passband of the LTC1164-8 is tuned with an external clock and the clock-to-center frequency ratio is 100:1. The – 3dB pass bandwidth is typically 1% of the filter center frequency. The stopband attenuation of the LTC1164-8 is greater than 50dB. The lower and upper stopband frequencies are less than 0.96 • center frequency and greater than 1.04 • center frequency, respectively. The LTC1164-8 requires an external op amp and two external resistors (see the circuit below). The filter’s gain at center frequency is set by the ratio RIN /RF. For a gain equal to one and an optimum dynamic range, RF should be set to 61.9k and RIN should be 340k. For gains other than one, RIN = 340k/Gain. Gains up to 1000 are obtainable. Setting the filter’s gain with input resistor RIN does not increase the filter’s wideband noise. The 270μVRMS wideband noise of the LTC1164-8 is independent of the filter’s center frequency. The LTC1164-8 is available in a 14-pin PDIP or a 16-pin surface mount SO Wide package. , LTC and LT are registered trademarks of Linear Technology Corporation. Ultraselectivity (50dB Attenuation at ± 4% of Center Frequency) Adjustable Passband Gain Noise Independent of Gain Filter Noise: 270μVRMS, VS = Single 5V Supply Clock-Tunable (Center Frequency = fCLK /100) Center Frequencies up to 5kHz, VS = ± 5V (Typical ISUPPLY = 3.2mA) Center Frequencies up to 4kHz, VS = Single 5V Supply (Typical ISUPPLY = 2.3mA) APPLICATIONS ■ ■ ■ ■ Asynchronous Narrowband Signal Detectors Low Frequency Asynchronous Demodulators Handheld Spectrum Analyzers In-Band Tone Signaling Detectors TYPICAL APPLICATION Ultranarrow 1kHz Bandpass Filter with Gain = 10 Gain = 340k/R IN, 1/(2π • RF • CF) ≥ 10 • Center Frequency RIN 34k VIN 5V 1 2 3 4 5 6 7 LTC1164-8 14 13 11 10 9 8 3 SHORT CONNECTION UNDER IC AND SHIELDED BY A GROUND PLANE 2 12 CF 200pF RF 61.9k 5V 30 20 10 0 GAIN (dB) –5V 100kHz –10 –20 –30 –40 – + 7 6 VOUT LT ®1006 4 –5V –50 –60 LTC1164-8 • TA01 –70 0.90 U U U Frequency Response 50dB 0.95 1.05 1.00 FREQUENCY (kHz) 1.10 1.15 1164-8 TA02 11648fb 1 LTC1164-8 ABSOLUTE MAXIMUM RATINGS Total Supply Voltage (V + to V –) .......................... 16.5V Power Dissipation ............................................. 700mW Burn-In Voltage ................................................... 16.5V Voltage at Any Input .... (V – – 0.3V) ≤ VIN ≤ (V + + 0.3V) Operating Temperature Range* .................. 0°C to 70°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C Maximum Clock Frequency VS = ± 7.5V .................................................... 720kHz VS = ± 5V ....................................................... 540kHz VS = Single 5V ............................................... 430kHz *For an extended operating temperature range contact LTC Marketing for details. PACKAGE/ORDER INFORMATION TOP VIEW NC INVB AGND V+ AGND NC INVA 1 2 3 4 5 6 7 N PACKAGE 14-LEAD PDIP TJMAX = 110°C, θJA = 65°C/ W ORDER PART NUMBER 14 R(h, l) 13 NC 12 V – 11 fCLK 10 NC 9 8 IOUT NC LTC1164-8CN Consult factory for Industrial and Military grade parts. ELECTRICAL CHARACTERISTICS PARAMETER Gain at Center Frequency VS = ± 2.375V VS = ± 5V Gain at 0.995 • Center Frequency and 1.005 • Center Frequency (Referenced to Gain at Center Frequency) Lower Stopband Attenuation (Referenced to Gain at Center Frequency) VS = ± 2.375V VS = ± 5V VS = ± 2.375V (See Test Circuit) TA = 25°C, Center Frequency = fCLK /100, fCLK = 100kHz (the clock signal is a TTL or CMOS square wave, clock rise or fall time ≤ 1μs), the AC test signal level is 1VRMS for VS = ± 5V or 0.5VRMS for VS = ± 2.375V, unless otherwise specified. CONDITIONS fIN = 1000Hz ● VS = ± 5V 2 U U W WW U W TOP VIEW NC INVB AGND V+ AGND NC NC INVA 1 2 3 4 5 6 7 8 16 R(h, l) 15 NC 14 V – 13 NC 12 fCLK 11 NC 10 NC 9 IOUT ORDER PART NUMBER LTC1164-8CSW SW PACKAGE 16-LEAD PLASTIC SO WIDE TJMAX = 110°C, θJA = 85°C/ W MIN –3 –4 –3 –4 –9 –9 TYP 0 ± 1.5 0 ± 2.0 0 ± 1.5 0 ± 2.0 MAX 3 4 3 4 3 3 UNITS dB dB dB dB dB dB dB dB dB dB dB dB dB fIN = 1000Hz ● fIN = 995Hz fIN = 1005Hz fIN = 995Hz fIN = 1005Hz fIN = 960Hz (Note 1) fIN = 800Hz fIN = 960Hz (Note 1) fIN = 800Hz ● ● ● – 48 – 50 – 48 – 48 – 3 ±2 – 3 ±2 – 52 – 52 – 52 – 52 – 58 – 60 11648fb LTC1164-8 ELECTRICAL CHARACTERISTICS PARAMETER Upper Stopband Attenuation (Referenced to Gain at Center Frequency) VS = ± 2.375V (See Test Circuit) TA = 25°C, Center Frequency = fCLK /100, fCLK = 100kHz ( the clock signal is a TTL or CMOS square wave, clock rise or fall time ≤ 1μs), the AC test signal level is 1VRMS for VS = ± 5V or 0.5VRMS for VS = ± 2.375V, unless otherwise specified. CONDITIONS fIN = 1040Hz (Note 1) fIN = 1200Hz ● MIN – 48 – 50 – 48 – 48 TYP – 52 – 52 – 52 – 52 1.0 2.5 – 40 ± 50 – 50 ± 60 2.3 MAX – 58 – 60 UNITS dB dB dB dB dB VRMS VRMS mV mV VS = ± 5V Maximum Output for < 0.25% Total Harmonic Distortion Output DC Offset Power Supply Current (Note 2) VS = ± 2.5V VS = ± 5V fIN = 1040Hz (Note 1) fIN = 1200Hz fIN = 1000Hz fIN = 1000Hz VS = ± 2.5V (At the Output of External Op Amp) VS = ± 5V VS = ± 2.375V ● 4.0 4.5 7.0 8.0 11.0 12.5 ±8 mA mA mA mA mA mA V VS = ± 5V ● 3.2 4.5 ● VS = ± 7.5V Power Supply Range The ● denotes specifications which apply over the full operating temperature range. Note 1: The minimum stopband attenuation at 960Hz and 1040Hz is guaranteed by design and test correlation. ± 2.375 Note 2: The maximum current over temperature is at 0°C. At 70°C the maximum current is less than its maximum value at 25°C. TYPICAL PERFORMANCE CHARACTERISTICS Gain vs Frequency TA = 25°C 0 VS = ± 5V = 100kHz f –10 CLK –20 10 GAIN (dB) GAIN (dB) –6 –9 –12 –15 –18 990 VS = ± 7.5V GAIN (dB) –30 –40 –50 –60 –70 –80 –90 760 880 1120 1000 FREQUENCY (Hz) 1240 LTC1164-8 • TPC01 UW Passband Variations vs Power Supply fCLK = 100kHz GAIN = 1 0 R = 340k IN RF = 61.9k –3 3 6 Passband Gain and Phase vs Frequency VS = ± 2.5V 3 0 –3 TA = 25°C VS = ± 5V fCLK = 100kHz 180 120 60 0 VS = ± 5V PHASE (DEG) –6 –9 –12 –15 –18 –21 –24 –60 –120 –180 –240 –300 –360 984 992 1008 1000 FREQUENCY (Hz) 1016 LTC1164-8 • TPC03 995 1000 FREQUENCY (Hz) 1005 1010 –420 LTC1164-8 • TPC02 11648fb 3 LTC1164-8 TYPICAL PERFORMANCE CHARACTERISTICS Passband Gain and Delay vs Frequency 6 TA = 25°C 3 VS = ± 5V = 100kHz f 0 CLK –3 GAIN (dB) 20 LOG (THD + NOISE/VIN) (dB) 80 70 DELAY (ms) –32 –38 –44 –50 –56 –62 –68 –74 –80 0.01 20 LOG (THD + NOISE/VIN) (dB) –6 –9 –12 –15 –18 –21 –24 984 992 1008 1000 FREQUENCY (Hz) 1016 LTC1164-8 • TPC04 THD + Noise vs Input Voltage TA = 25°C VS = SINGLE 5V fIN = 1kHz –50 fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 –60 –40 POWER SUPPLY CURRENT (mA) 20 LOG (THD + NOISE/VIN) (dB) OUTPUT LEVEL (dBV) AGND AT 2.5V AGND AT 2V –70 –80 0.5 1.0 1.5 2.0 2.5 INPUT VOLTAGE (VP-P) 3.0 3.5 4 UW LTC1164-8 • TPC07 THD + Noise vs Input Voltage 100 90 –20 –26 TA = 25°C VS = ± 5V fIN = 1kHz fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 –20 –26 –32 –38 –44 –50 –56 –62 –68 –74 0.1 1 INPUT VOLTAGE (VRMS) 5 THD + Noise vs Input Voltage TA = 25°C VS = SINGLE 5V fIN = 1kHz fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 AGND = 2.5V AGND = 2V 60 50 40 30 20 10 0 –80 0.01 0.1 INPUT VOLTAGE (VRMS) 1 2 LTC1164-8 • TPC05 LTC1164-8 • TPC06 Power Supply Current vs Power Supply Voltage 5.0 25°C 70°C 3.0 10 0 –10 –20 –30 –40 –50 Output vs Input fCLK = 100kHz fCENTER = 1kHz fIN = 1kHz 4.0 VS = SINGLE 5V (PINS 3, 5 AT 2V) 2.0 1.0 VS = ± 5V 0 0 0.8 1.6 2.4 3.2 4.0 4.8 5.6 6.4 7.2 8.0 POWER SUPPLY VOLTAGE (V + OR V –) LTC1164-8 • TPC08 –60 –60 –50 –40 –30 –20 –10 INPUT LEVEL (dBV) 0 10 LTC1164-8 • TPC09 11648fb LTC1164-8 PIN FUNCTIONS V +, V – (Pins 4, 12): Power Supply Pins. The V + (Pin 4) and the V – (Pin 12) should be bypassed with a 0.1μF capacitor to a reliable ground plane. The filter’s power supplies should be isolated from other digital or high voltage analog supplies. A low noise linear supply is recommended. Using a switching power supply will lower the signal-to-noise ratio of the filter. The power supply during power-up should have a slew rate of less than 1V/μs. For dual supply operation if the V + supply is applied before the V – supply or the V – supply is applied before the V + supply, a signal diode on each supply pin to ground will prevent latchup. Figures 1 and 2 show typical connections for dual and single supply operation. fCLK (Pin 11): Clock Input Pin. Any TTL or CMOS clock source with a square wave output and 50% duty cycle (±10%) is an adequate clock source for the device. The VIN 7 8 Figure 1. Dual Power Supply Operation (Gain = 1) RF 61.9k 5V fCLK RIN 340k VIN 1 2 3 14 13 12 LTC1164-8 11 10 5V 0.1μF 15k 4 5 6 7 + 8 Figure 2. Single Power Supply Operation (Gain = 1) 11648fb + 1μF 10k 3 – 9 2 + *FOR SURFACE MOUNT CIRCUITS USE MOTOROLA DIODE MBR0530 OR EQUIVALENT 3 – 5V *1N4148 OR EQUIVALENT U U U (14-Lead PDIP) power supply for the clock source should not be the filter’s power supply. The analog ground for the filter should be connected to the clock’s ground at a single point only. Table 1 shows the clock’s low and high level threshold values for dual or single supply operation. A pulse generator can be used as a clock source provided the high level on-time is at least 1μs. Sine waves are not recommended for clock input frequencies less than 100kHz. The clock’s rise or fall time should be equal to or less than 1μs. Table 1. Clock Source High and Low Threshold Levels POWER SUPPLY Single Supply = 5V Single Supply = 12V Dual Supply = ± 2.5V Dual Supply = ± 5V Dual Supply = ± 7.5V HIGH LEVEL >1.45V >7.80V >0.73V >1.45V >2.18V LOW LEVEL