LTC1067 Linear Technology, LTC1067 Datasheet
LTC1067
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LTC1067 Summary of contents
Page 1
... The center frequency of each 2nd order section is tuned by the external clock frequency. The internal clock-to-center frequency ratio (100:1 for the LTC1067 and 50:1 for the LTC1067-50) can be modified by the external resistors. These devices have a double sampled architecture which places aliasing and imaging components at twice the clock frequency ...
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... Input Voltage ........................ (V + 0.3V Output Short-Circuit Duration .......................... Indefinite Power Dissipation............................................... 500mV Operating Temperature Range LTC1067C................................................ LTC1067I............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C ELECTRICAL CHARACTERISTICS PARAMETER CONDITIONS Operating Supply Range Positive Output Voltage Swing ...
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... OS2 V OS3 Clock Feedthrough Maximum Clock Frequency Q < 2.5, V Power Supply Current 4.75V 5V LTC1067-50 (internal op amps 4.75V PARAMETER CONDITIONS Operating Supply Range Positive Output Voltage Swing 4.75V 5V Negative Output Voltage Swing ...
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... C, unless otherwise noted. CLK A (DC Offset of Input Inverter) (DC Offset of First Integrator) (DC Offset of Second Integrator 125kHz CLK = 125kHz CLK = 250kHz CLK Note 1: See Typical Performance Characteristics. LTC1067 Maximum Q vs Center Frequency (Modes 2 where R4 < 10R2 2MHz CLK(MAX ...
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... CLK(MAX 3. 800kHz CLK(MAX 600kHz CLK(MAX CENTER FREQUENCY, f (kHz) O 1067 G14 LTC1067/LTC1067-50 LTC1067 Noise vs Q 220 200 5V 180 160 140 5V 120 100 LTC1067 Power Supply Current vs Power Supply 4 ...
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... S CLK – 5kHz IN RMS –3dB R = 20k L –70 MODE 1 –75 MODE 3 –80 –85 – INPUT FREQUENCY (kHz) LTC1067-50 Output Voltage Swing vs Load Resistance, Single Supply Voltage 5 4.5 S 4.0 3.5 3 2.5 2.0 1.5 1 – LOAD RESISTANCE ( ...
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... 0 200 CLOCK SOURCE FOR MODE 3, THE SA AND SB SUMMING NODE PINS 1067 F01 ARE TIED TO THE AGND PIN Figure 2. Single Supply Ground Plane Connections LTC1067/LTC1067-50 LTC1067/LTC1067-50 Mode 3 Noise Increase vs R2/R4 Ratio 2.0 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.6 0.8 0.9 1.0 0.2 0.3 0.4 0.5 0.7 R2/R4 RATIO ...
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... LPA, BPA, HPA/NA, HPB/NB, BPB, LPB (Pins 10, 11, 12): Output Pins. Each 2nd order section of the LTC1067 has three outputs which typically source 33mA and sink 2mA. Driving coaxial cable, capacitive loads or resistive loads less than 10k will degrade the total har- monic distortion performance of any filter design ...
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... W ODES OF OPERATIO Linear Technology’s universal switched-capacitor filters are designed with a fixed internal, nominal f The LTC1067 has a 100:1 f CLK LTC1067-50 has a 50 ratio. Filter designs often CLK O require the f /f ratio of each section to be different from CLK O the nominal ratio and in most cases different from each other ...
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... CLK 1.005 O RATIO – (RATIO)(0.32)(R4 – – OHP OBP – (RATIO)(0.32)(R4) NOTE: RATIO = 100 FOR LTC1067 = 50 FOR LTC1067- HPN S – – CLK CLK RATIO RATIO ...
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... R3 1 – (RATIO)(0.32)(R4 OLPn FOR LTC1067- HIGHPASS OR LOWPASS NOTCH OUTPUT EXTERNAL OP AMP OR INPUT OP AMP OF THE LTC1067, SIDES 1067 F07 R2 CLK 0 ...
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... Please refer to Figures 3 through 8. The value of C can be best determined experimentally, and guide it should be about 5pF for each 1dB of gain error and not to exceed 15pF. When operating the LTC1067 near the Table 2. Output DC Offsets for a Second Order Section MODE V OSHP/N ...
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... The 1 probe will probably cause oscillation. ) that falls into the IN What to Do with an Unused Section If the LTC1067 or LTC1067-50 is used as a single 2nd . If the CLK order filter, the other 2nd order section is not used. Do not leave this section unconnected. If the section is uncon- nected, inputs and outputs are left to float to undetermined levels and oscillation may occur ...
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... ADC running on a single 5V supply with a 4.096 reference voltage is a standard example. The LTC1067 or LTC1067-50 will easily reach the 4.096V level for a full- scale reading. The issue is how close does the output go to ground. The further the output is from ground, the more codes that are essentially lost ...
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... ADC and a 0V input signal gives the lowest possible value. For this application, the power supply must be above 2.7V for an LTC1067-50 filter and above 3V for an LTC1067 filter ...
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... IN TP10 Figure 15. Schematic for the LTC1067/LTC1067-50 Demo Board Several other jumpers should be connected as follows: JP1: Install a jumper wire from position 1 to position 2, leave the other positions open. JP5: Install a jumper wire if split supply, leave open if single supply. ...
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... U U APPLICATIONS INFORMATION Figure 16. Silkscreen for the LTC1067/LTC1067-50 Demo Board U TYPICAL APPLICATIONS 5th Order Lowpass with Input RC (Fixed Frequency) 5V 0.1 F R41, 20k R31, 47. R21, 22.6k R IN1 R IN2 16.9k 22.6k C IN1 1500pF 5% Frequency Response (f CUTOFF 10 0 –10 –20 –30 –40 –50 –60 –70 –80 – ...
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... CENTER CLK CENTER CLK 64kHz AGND – R62 SA SB R52 8.66k LTC1067-50 4.99k 12 5 LPA LPB R32, 255k 11 6 BPA BPB R22, 4.99k 10 7 HPA/NA HPB/ INV A INV 115k B1 –5V 0 (OR 2.5V) 3V (OR 1.5V) ...
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... U TYPICAL APPLICATIONS Gain vs Frequency – 500 700 900 1100 1300 1500 FREQUENCY (kHz) 1067 TA07b LTC1067 Dual Bandpass Filters 150kHz (f S CLK CENTER1 0 R61 3 15k + V 4 R51 SA LTC1067 4.99k 5 LPA R31, 232k ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE U TYPICAL APPLICATION 1.02kHz Notch Filter for Telecom System 0 R61, 9.88k LTC1067 R51, 4.99k* 5 LPA R31, 61.9k 6 BPA R21, 10k 7 HPA/NA HPB/NB C21, 300pF** 8 INV A RH1, 40.2k V *** IN R11, 18.7k R51, R61, R52, R62 ARE 0 ...