LTC1164-8 Ultraselective, Low Power 8th Order Elliptic Bandpass Filter with Adjustable Gain U DESCRIPTION FEATURES ■ ■ ■ ■ ■ ■ ■ 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. 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) 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. U APPLICATIONS ■ ■ ■ ■ Asynchronous Narrowband Signal Detectors Low Frequency Asynchronous Demodulators Handheld Spectrum Analyzers In-Band Tone Signaling Detectors 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. U TYPICAL APPLICATION Frequency Response Ultranarrow 1kHz Bandpass Filter with Gain = 10 Gain = 340k/R IN, 1/(2π • RF • CF) ≥ 10 • Center Frequency VIN 5V 1 14 2 13 3 12 4 LTC1164-8 11 5 10 6 9 7 8 20 CF 200pF 10 0 RF 61.9k –5V GAIN (dB) RIN 34k 30 100kHz 5V 2 7 LT ®1006 3 SHORT CONNECTION UNDER IC AND SHIELDED BY A GROUND PLANE – + 6 –20 –30 –40 VOUT 4 –5V 50dB –10 –50 –60 LTC1164-8 • TA01 –70 0.90 0.95 1.05 1.00 FREQUENCY (kHz) 1.10 1.15 1164-8 TA02 1 LTC1164-8 W W U W 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. U W U PACKAGE/ORDER INFORMATION ORDER PART NUMBER TOP VIEW NC 1 INVB 2 13 NC AGND 3 12 V – V+ 4 11 fCLK AGND 5 NC 6 9 IOUT INVA 7 8 NC 14 R(h, l) LTC1164-8CN 10 NC ORDER PART NUMBER TOP VIEW NC 1 16 R(h, l) INVB 2 15 NC AGND 3 14 V – V+ 4 13 NC AGND 5 12 fCLK NC 6 11 NC NC 7 10 NC INVA 8 9 N PACKAGE 14-LEAD PDIP LTC1164-8CSW IOUT SW PACKAGE 16-LEAD PLASTIC SO WIDE TJMAX = 110°C, θJA = 65°C/ W TJMAX = 110°C, θJA = 85°C/ W Consult factory for Industrial and Military grade parts. ELECTRICAL CHARACTERISTICS (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. PARAMETER Gain at Center Frequency CONDITIONS VS = ±2.375V fIN = 1000Hz ● VS = ±5V fIN = 1000Hz Gain at 0.995 • Center Frequency and 1.005 • Center Frequency (Referenced to Gain at Center Frequency) VS = ±2.375V Lower Stopband Attenuation (Referenced to Gain at Center Frequency) VS = ±2.375V fIN = 995Hz fIN = 1005Hz fIN = 995Hz fIN = 1005Hz fIN = 960Hz (Note 1) fIN = 800Hz ● VS = ±5V ● ● ● VS = ±5V 2 fIN = 960Hz (Note 1) fIN = 800Hz MIN TYP –3 –4 –3 –4 –9 –9 0 ± 1.5 0 ± 2.0 0 ± 1.5 0 ± 2.0 – 48 – 50 – 48 – 48 – 3 ±2 – 3 ±2 – 52 – 52 – 52 – 52 MAX 3 4 3 4 3 3 – 58 – 60 UNITS dB dB dB dB dB dB dB dB dB dB dB dB dB LTC1164-8 ELECTRICAL CHARACTERISTICS (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. PARAMETER Upper Stopband Attenuation (Referenced to Gain at Center Frequency) VS = ±2.375V CONDITIONS MIN TYP fIN = 1040Hz (Note 1) – 48 – 52 – 50 – 48 – 52 – 48 – 52 – 52 dB dB 1.0 2.5 VRMS VRMS fIN = 1200Hz ● VS = ±5V fIN = 1040Hz (Note 1) fIN = 1200Hz Maximum Output for < 0.25% Total Harmonic Distortion VS = ±2.5V VS = ±5V fIN = 1000Hz fIN = 1000Hz Output DC Offset VS = ±2.5V (At the Output of External Op Amp) VS = ±5V Power Supply Current (Note 2) VS = ±2.375V UNITS dB – 58 – 60 dB dB – 40 ±50 – 50 ±60 VS = ±5V 4.0 4.5 mA mA 3.2 7.0 8.0 mA mA 4.5 11.0 12.5 mA mA ±8 V ● VS = ±7.5V ● ±2.375 Power Supply Range mV mV 2.3 ● 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. MAX 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. U W TYPICAL PERFORMANCE CHARACTERISTICS Passband Variations vs Power Supply Gain vs Frequency 10 6 3 fCLK = 100kHz GAIN = 1 0 R = 340k IN RF = 61.9k –3 –20 GAIN (dB) –40 –50 –60 0 VS = ±5V –6 VS = ±7.5V –9 –12 –70 –15 –80 –90 760 880 1120 1000 FREQUENCY (Hz) 1240 –18 990 1000 1005 1010 LTC1164-8 • TPC02 180 120 60 –3 0 –6 –60 –9 –120 –12 –180 –15 –240 –18 –300 –21 –360 –24 995 FREQUENCY (Hz) LTC1164-8 • TPC01 TA = 25°C VS = ±5V fCLK = 100kHz 3 984 992 1008 1000 FREQUENCY (Hz) 1016 PHASE (DEG) –30 VS = ±2.5V GAIN (dB) TA = 25°C 0 VS = ±5V = 100kHz f –10 CLK GAIN (dB) Passband Gain and Phase vs Frequency –420 LTC1164-8 • TPC03 3 LTC1164-8 U W TYPICAL PERFORMANCE CHARACTERISTICS Passband Gain and Delay vs Frequency THD + Noise vs Input Voltage 90 –26 80 –3 70 –6 60 –9 50 –32 –38 –56 –15 30 –18 20 –21 10 –74 0 –80 0.01 992 1008 1000 FREQUENCY (Hz) 1016 –62 –68 0.1 1 INPUT VOLTAGE (VRMS) –80 1.5 2.0 2.5 INPUT VOLTAGE (VP-P) 3.0 3.5 LTC1164-8 • TPC07 4 AGND = 2.5V AGND = 2V –62 –68 0.1 INPUT VOLTAGE (VRMS) 1 2 LTC1164-8 • TPC06 Output vs Input 10 0 25°C 4.0 70°C 3.0 2.0 OUTPUT LEVEL (dBV) POWER SUPPLY CURRENT (mA) 20 LOG (THD + NOISE/VIN) (dB) AGND AT 2V 1.0 –50 –56 –80 0.01 5 5.0 AGND AT 2.5V 0.5 –44 Power Supply Current vs Power Supply Voltage –40 –70 –38 LTC1164-8 • TPC05 THD + Noise vs Input Voltage –60 –32 –74 LTC1164-8 • TPC04 TA = 25°C VS = SINGLE 5V fIN = 1kHz –50 fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 TA = 25°C VS = SINGLE 5V fIN = 1kHz fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 –26 –50 40 984 TA = 25°C VS = ±5V fIN = 1kHz fCLK = 100kHz FILTER GAIN AT fCENTER = 1 OUTPUT OP AMP IS LT1006 –44 –12 –24 THD + Noise vs Input Voltage –20 20 LOG (THD + NOISE/VIN) (dB) –20 DELAY (ms) GAIN (dB) TA = 25°C 3 VS = ±5V = 100kHz f 0 CLK 100 20 LOG (THD + NOISE/VIN) (dB) 6 fCLK = 100kHz fCENTER = 1kHz fIN = 1kHz –10 –20 VS = SINGLE 5V (PINS 3, 5 AT 2V) –30 –40 1.0 VS = ± 5V –50 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 LTC1164-8 U U U PIN FUNCTIONS (14-Lead PDIP) 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. 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. 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. Table 1. Clock Source High and Low Threshold Levels POWER SUPPLY 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 RIN 340k VIN 1 14 2 13 3 4 5V *1N4148 OR EQUIVALENT 0.1µF >1.45V <0.5V Single Supply = 12V >7.80V <6.5V Dual Supply = ±2.5V >0.73V <– 2.0V Dual Supply = ±5V >1.45V <0.5V Dual Supply = ±7.5V >2.18V <0.5V RF 61.9k 11 5 10 6 9 7 8 LOW LEVEL Single Supply = 5V 12 LTC1164-8 HIGH LEVEL fCLK 0.1µF 5V –5V 1N4148* OR EQUIVALENT 0.1µF – 2 7 6 *FOR SURFACE MOUNT CIRCUITS USE MOTOROLA DIODE MBR0530 OR EQUIVALENT VOUT + 3 LTC1164-8 • F01 4 0.1µF –5V Figure 1. Dual Power Supply Operation (Gain = 1) RIN 340k VIN 14 2 13 3 12 4 5V 0.1µF 15k + 1µF 1 10k LTC1164-8 11 5 10 6 9 7 8 RF 61.9k 5V fCLK 0.1µF 2 – 3 + 7 6 VOUT 4 LTC1164-8 • F02 Figure 2. Single Power Supply Operation (Gain = 1) 5 LTC1164-8 U U U PIN FUNCTIONS AGND (Pins 3, 5): Analog Ground Pins. For dual supply operation, Pins 3 and 5 (AGND) are connected to an analog ground plane. For single supply operation, Pins 3 and 5 should be biased at 1/2 of the V + supply and be bypassed to the analog ground plane with a 1µF (tantalum or better) capacitor (Figure 2). For optimum gain linearity and single 5V supply operation, the analog ground Pins 3 and 5 should be biased at 2V. Under these conditions the typical output AC swing is 0.5V to 3.5V (please refer to the THD + Noise vs Input Voltage graph). The filter performance depends on the quality of the analog ground. For either a dual or a single supply operation, an analog ground plane surrounding the package is necessary. The analog ground plane for the filter should be connected to any digital ground plane at a single point. INVB, INVA, IOUT, [R (h, l]) (Pins 2, 7, 9, 14): External Connection Pins. Pin 2 (INVB) is the inverting input on an op amp. Pin 9 (IOUT) is the junction of two internal resistors. Pin 7 (INVA) is the inverting input of an op amp, Pin 14 [R (h, l)] is the junction of two internal resistors. For normal filter operation an external input resistor (RIN) should be connected to input Pin 2 and the output Pin 9 should be connected to the inverting input of an external op amp with a feedback resistor (RF). Also Pins 7 and 14 should be connected together (Figures 1 and 2). On a printed circuit board the external connections should be less than one inch and surrounded by a ground plane. The input resistor and output op amp with feedback resistor determine the filter’s gain and dynamic range. Please refer to the Applications Information section for more information. NC (1, 6, 8, 10, 13): NC Pins. Pins 1, 6, 8, 10 and 13 are not connected to any circuit point on the device and should be tied to analog ground for dual or single supply operation. TEST CIRCUIT 100pF RIN 340k VIN 14 2 13 3 12 4 VS 1N4148 1 0.1µF LTC1164-8 61.9k –VS 11 5 10 6 9 7 8 0.1µF 15V 1N4148 2 – 3 + 0.1µF 7 LT1220 6 VOUT 4 fCLK 100kHz –15V 0.1µF LTC1164-8 • TC 6 LTC1164-8 U U W U APPLICATIONS INFORMATION 3 Passband Gain and Dynamic Range VS = ±5V RIN = 340k 0 R = 61.9k F The filter’s gain at fCENTER is set with an external op amp and resistors RIN and RF (Figure 1). The filter’s center frequency (fCENTER) is equal to the clock frequency divided by 100. The output dynamic range of LTC1164-8 is optimized for minimum noise and maximum voltage swing when resistor RF is 61.9k. The value of resistor RIN depends on the filter’s gain and it is calculated by the equation RIN = 340k/Gain. Table 2 lists the values of RIN and RF for some typical gains. Increasing the filter’s gain with resistor RIN does not increase the noise generated by the filter. Table 3 shows the noise generated by the filter with its input grounded. Table 2. Passband Gain at Center Frequency, RIN and RF GAIN RIN (±1%) RF (±1%) 1 340k 61.9k GAIN IN dB RIN (±1%) 0 340k RF (±1%) 61.9k GAIN (dB) –3 –6 –9 –12 –15 –18 –0.50 fCENTER 1.00 0.50 –1.00 PERCENT DEVIATION FROM fCENTER (±% fCENTER) LTC1164-8 • F03 Figure 3. Typical Passband Variations the filter, only a small amount of input noise will reach the filter’s output. If the output noise of the LTC1164-8 is neglected, the signal-to-noise ratio at the output of the filter divided by the signal-to-noise ratio at the input of the filter equals: 2 169k 61.9k 10 107k 61.9k 5 68.1k 61.9k 15 60.4k 61.9k 10 34k 61.9k 20 34k 61.9k 20 16.9k 61.9k 25 19.1k 61.9k 50 6.81k 61.9k 30 10.7k 61.9k where, 100 3.4k 61.9k 35 6.01k 61.9k 200 1.69k 61.9k 40 3.4k 61.9k 500 680Ω 61.9k 45 1.91k 61.9k (BW)IN = noise bandwidth at the input of the filter (BW)f = 0.01 • fCENTER = noise equivalent filter bandwidth 1000 340Ω 61.9k 50 1.07k 61.9k Table 3. LTC1164-8 Noise with Its Input Grounded POWER SUPPLY NOISE (µVRMS) ±5V Single 5V 360 ±10% 270 ±10% The passband of the LTC1164-8 is from 0.995 • fCENTER to 1.005 • fCENTER. At the passband’s end points the typical filter gain is – 3dB ±2dB relative to the gain at fCENTER. Figure 3 shows typical passband gain variations versus percent of frequency deviation from fCENTER. Outside the filter’s passband, signal attenuation increases to – 50dB for frequencies less than 0.96 • fCENTER and greater than 1.04 • fCENTER. In applications where a signal is to be detected in the presence of wideband noise, the ultraselectivity of the LTC1164-8 can improve the output signal-to-noise ratio. When wideband noise (white noise) appears at the input to (S/N)OUT/(S/N)IN = 20 • Log √(BW)IN/(BW)f Example: A small 1kHz signal is sent through a cable that also conducts random noise. The cable bandwidth is 3.4kHz. An LTC1164-8 is used to detect the 1kHz signal. The signal-to-noise ratio at the output of the filter is 25.3dB larger than the signal-to-noise ratio at the input of the filter (20 • Log√(BW)IN/(BW)f = 20 • Log√3.4kHz/ 0.01 • 1kHz 1kHz = 25.3dB). The AC output swing with ±5V supplies is ±4V, with a single 5V supply it is 1V to 4V, when AGND (Pins 3, 5) is biased at 2.5V. Table 4 lists op amps that are recommended for use with an LTC1164-8. The LTC1164-8 is designed and specified for a dual ±5V or single 5V supply operation. The filter’s passband gain linearity is optimum at single 5V supply and with Pins 3, 5 (AGND) biased at 2V. Filter operation at ±7.5V supplies is not tested or specified. At VS = 7.5V, the filter will operate with center frequencies up to 7kHz. Please refer to the Passband Variations vs Power Supply graph in the Typical Performance Characteristics. 7 LTC1164-8 U W U U APPLICATIONS INFORMATION Table 4. Recommended Op Amps for LTC1164-8 Clock Feedthrough DUAL QUAD LT1006 LT1012 LT1077 LT1013 LT1078 LT1112 LT1413 LT1014 LT1079 LT1114 A 10mV/DIV SINGLE B Aliasing At the filter’s output, alias signals will appear when signals at the filter’s input have substantial energy very near the clock frequency or any of its multiples (2 • fCLK, 3 • fCLK, ... etc.). For example, if an LTC1164-8 filter operates with a 100kHz clock and has a 99kHz, 10mV signal at its input, a 1kHz, 10mV alias signal will appear at the filter’s output. Table 5 shows details. Table 5. Aliasing (fCLK = 100kHz) 5µs/DIV LTC1164-8 • F04 Figure 4. Clock Feedthrough at the Output of External Op Amp A. With No Capacitor Across Feedback Resistor RF B. With Capacitor CF Across Feedback Resistor RF 1/(2π • RF • CF) = 10 • fCENTER OUTPUT FREQUENCY (ALIAS FREQUENCY) 99.04kHz (or 100.96kHz) < – 50dB 960Hz 99.02kHz (or 100.98kHz) < – 40dB 980Hz 99.01kHz (or 100.99kHz) < – 6dB 990Hz 99.005kHz (or 100.995Hz) – 3dB ±2dB 995Hz 99.00kHz (or 101.00kHz) 0dB ±1dB 1000Hz 98.995kHz (or 101.005kHz) – 3dB ±2dB 1005Hz 98.99kHz (or 101.01kHz) < – 6dB 1010Hz 98.98kHz (or 101.02kHz) < – 40dB 1020Hz 98.96kHz (or 101.04kHz) < – 50dB 1040Hz 1V/DIV FOR INPUT 20mV/DIV FOR OUTPUT Transient Response OUTPUT LEVEL (RELATIVE TO INPUT) OUTPUT INPUT VS = ±5V fCLK = 500kHz fCENTER = 5kHz 5ms/DIV LTC1164-8 • F05 Figure 5. Square Wave Input (±2.5V) OUTPUT 2V/DIV INPUT FREQUENCY LT1006 VS = ±5V fCLK = 100kHz INPUT VS = ±5V fCLK = 100kHz fCENTER = 1kHz 50ms/DIV Figure 6. Sine Wave Burst Input 8 LTC1164-8 • F06 LTC1164-8 U U W U APPLICATIONS INFORMATION Printed Circuit Layout For optimum filter performance, an LTC1164-8 should be operating on a printed circuit board that has been laid out for precision analog signal processing circuits. On a printed circuit board, an LTC1164-8 should be surrounded with an adequate analog signal ground plane and its power supply pins bypassed to ground with 0.1µF capacitors. The ground plane of an LTC1164-8 and any digital ground plane should preferably meet at a single point on a system ground (star system ground). The following external filter connections should be one inch or less: N Package Resistor RIN to Pin 2 Pin 14 to Pin 7 Pin 9 to the Inverting Node of an External Op Amp Ground Pins 1, 3, 5, 6, 8, 10 and 13 SW Package Resistor RIN to Pin 2 Pin 16 to Pin 8 Pin 9 to the Inverting Node of External Op Amp Ground Pins 1, 3, 5, 6, 7, 10, 11, 13 and 15 Any signal or power supply printed circuit traces should be at least 0.2 inches away from the above mentioned connections (this rule applies also to the routing of the printed circuit trace originating from a clock source in a digital circuit and terminating at a clock input pin of an LTC1164-8). Operating an LTC1164-8 in an IC socket is not recommended. U TYPICAL APPLICATIONS N Tone Detector and Average Value Circuit RIN 340k VIN 14 2 13 3 12 4 5V 1N4148 1 0.1µF LTC1164-8 CF 5 10 6 9 7 8 RF 61.9k –5V 11 0.1µF 1N4148 – C1 R1 10k 1/2 LT1413 + 5k 1N458 5k 1N458 A B – 1/2 LT1413 + fCLK 100kHz 5k 5V – 5k R2 100k 5k 0.1µF 4 5k – R3 100k + 1/2 LT1413 + A C2 11 –5V 0.1µF 1/2 LT1413 B VOUT = AVERAGE OF ABS [VPEAK × SIN (2π × fCENTER × t)], ±10% FROM 1VP-P TO 7VP-P RIN = 340k/GAIN; fCENTER = fCLK/100; 1/(2π × RF × CF) ≥ 10 × fCENTER 1/(2π × R1 × C1) ≤ fCENTER/10; 1/(2π × R2 × C2) ≤ fCENTER/25; R2 × C2 = R3 × C3 VOUT C3 LTC1164-8 • TA03 9 LTC1164-8 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. N Package 14-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.770* (19.558) MAX 14 13 12 11 10 9 8 1 2 3 4 5 6 7 0.255 ± 0.015* (6.477 ± 0.381) 0.130 ± 0.005 (3.302 ± 0.127) 0.300 – 0.325 (7.620 – 8.255) 0.045 – 0.065 (1.143 – 1.651) 0.015 (0.380) MIN 0.065 (1.651) TYP 0.009 – 0.015 (0.229 – 0.381) +0.025 0.325 –0.015 ( 8.255 +0.635 –0.381 ) 0.125 (3.175) MIN 0.075 ± 0.015 (1.905 ± 0.381) 0.100 ± 0.010 (2.540 ± 0.254) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm). 10 0.018 ± 0.003 (0.457 ± 0.076) N14 0694 LTC1164-8 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. SW Package 16-Lead Plastic Small Outline (Wide 0.300) (LTC DWG # 05-08-1620) 0.398 – 0.413 (10.109 – 10.490) (NOTE 2) 16 15 14 13 12 11 10 9 0.394 – 0.419 (10.007 – 10.643) NOTE 1 0.005 (0.127) RAD MIN 1 0.291 – 0.299 (7.391 – 7.595) (NOTE 2) 0.010 – 0.029 × 45° (0.254 – 0.737) 2 3 4 5 6 7 8 0.093 – 0.104 (2.362 – 2.642) 0.037 – 0.045 (0.940 – 1.143) 0° – 8° TYP 0.009 – 0.013 (0.229 – 0.330) NOTE 1 0.016 – 0.050 (0.406 – 1.270) 0.050 (1.270) TYP 0.004 – 0.012 (0.102 – 0.305) 0.014 – 0.019 (0.356 – 0.482) TYP NOTE: 1. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS. THE PART MAY BE SUPPLIED WITH OR WITHOUT ANY OF THE OPTIONS. 2. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006 INCH (0.15mm). 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. SOL16 0392 11 LTC1164-8 U TYPICAL APPLICATION Tone Detector — Detecting a Low Level Signal Buried in Wideband Noise fCLK RIN VIN 1 14 2 13 3 12 4 5V 5 0.1µF + 1µF LTC1164-8 5V CF R2 10k RF 61.9k 11 5V 18 10 6 9 7 8 1 – C1 1/2 LT1413 + 5V 4 R1 10k 0.1µF – 8 1/2 LT1413 + 30.1k AGND (2V) 0.1µF 0.1µF 0.1µF 1k REF1 (1.9V) 8.87k REF2 (1V) 10k 0.1µF FOR OPTIMUM TONE DETECTION, THE SIGNAL’S FREQUENCY SHOULD BE IN THE FILTER’S PASSBAND AND WITHIN ±0.1% FROM fCENTER. AT VOUT, LOGIC HIGH = SIGNAL AT VIN, LOGIC LOW = NO SIGNAL AT VIN. THE MINIMUM DETECTABLE SIGNAL AT VIN: VIN(MIN) = 200mVRMS/GAIN. THE MAXIMUM NOISE SPECTRAL DENSITY AT VIN: VIN = 32mVRMS/[GAIN • √(BW)f] WHERE:(BW) f = 0.01 • fCENTER AND IS THE NOISE EQUIVALENT BANDWIDTH OF THE FILTER GAIN = 340k/R IN AND IS THE FILTER GAIN AT fCENTER RIN = 340k/GAIN; fCENTER = fCLK/100; 1/(2π • RF • CF) ≥ 10 • fCENTER 1/(2π • R1 • C1) ≤ fCENTER/10; 1/(2π • R3 • C2) ≤ fCENTER/32 R3 10k STROBE LTC1040 5 6 7 8 + – + COMP1 – 4 14 REF2 13 C2 1V 12 11 + – + COMP2 – 15 REF1 1.9V VOUT LTC1164-8 • TA04 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC1064 Universal Filter Building Block This Part, with External Resistors, Allows Design of Bandpass Filters Similar to LTC1164-8 (Up to 50kHz) LTC1164 Universal Filter Building Block This Part, with External Resistors, Allows Design of Bandpass Filters Similar to LTC1164-8 (Low Power Up to 20kHz) LTC1264 Universal Filter Building Block This Part, with External Resistors, Allows Design of Bandpass Filters Similar to LTC1164-8 (Up to 100kHz) See Table 4 for additional information 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417● (408) 432-1900 FAX: (408) 434-0507● TELEX: 499-3977 ● www.linear-tech.com 11648fa LT/TP 1297 REV A 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1995