ltc1264-7csw-trpbf Linear Technology Corporation, ltc1264-7csw-trpbf Datasheet
ltc1264-7csw-trpbf
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ltc1264-7csw-trpbf Summary of contents
Page 1
... The clock-to-center frequency ratio is internally set to 20:1, but it can be modified via external resistors. The aliasing performance of the LTC1264 is improved by double-sampling each 2nd order section. Input signal frequencies can reach up to twice the clock frequency before any alias products will be detectable. ...
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... CLK f < 2MHz CLK U W TOP VIEW ORDER PART 1 24 INV C NUMBER 2 23 HPC/ BPC 4 21 LPC LTC1264CN LTC1264CSW – CLK LPD 10 15 BPD 11 14 HPD/ INV D SW PACKAGE 24-LEAD PLASTIC SO (WIDE) = 110°C, θ ...
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... MODES MODES 3.0 1.0 1.5 2.0 2.5 3.5 CLOCK FREQUENCY (MHz) LTC1264 = ±5V 1MHz, all sides mode CLK MIN TYP MAX ±20 ● ±45 ● ±45 ● 160 120 ● error is calculated as: O ...
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... LTC1264 W U TYPICAL PERFOR A Typical Bandpass Gain Error vs Clock Frequency 5 MODE 25° ± ±7. 2.0 2.4 2.8 3.2 3.6 4.0 CLOCK FREQUENCY (MHz) 1264 G04 Typical Bandpass Gain Error vs Clock Frequency 5 MODE 25° SINGLE ...
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... SHOULD BE TIED TO PIN 6 Figure 2. Single Supply Ground Plane Connections LTC1264 greater than 1MHz, pin 6 should be CLK LTC1264 DIGITAL GROUND 200Ω PLANE CLOCK SOURCE 1264 F02 ...
Page 6
... When evaluating the distortion or noise performance of a particular filter design imple- mented with an LTC1264, the final output of the filter should be buffered with a wideband noninverting high LOW LEVEL slew rate amplifier (Figure 3). ...
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... ON OBP AGND Figure 6. Mode 3, 2nd Order Section Providing Highpass, Bandpass and Lowpass Outputs LTC1264 . – – + Σ ∫ + 1/4 LTC1264 ( ) √ √ CLK 1.005 – – ...
Page 8
... OHPn frequency than the notch in Mode 2. This mode, shown in Figure 8, is most useful in lowpass elliptic designs. When cascading the sections of the LTC1264, the highpass notch and lowpass outputs can be summed directly into the inverting input of the next section. Please refer to the Maximum Frequency of Operation ...
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... √ 1.005 – 6.42•R4 LOWPASS NOTCH OUTPUT EXTERNAL OP AMP OR INPUT OP AMP OF THE LTC1264, SIDES 1264 G09 LPA + CLK ∫ + – LPB 4 ∫ + LPC 21 ∫ + LPD 16 ∫ + 1264 BD 1264fb ...
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... The value of C can be best determined experimentally, C and as a guide it should be about 5pF for each 1dB of gain error and not to exceed 15pF. When operating LTC1264 very near the limits defined by the Typical Performance Characteristics graphs, passband gain variations of 2dB or more should be expected. ...
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... PPLICATI S I FOR ATIO A For example, for an LTC1264 bandpass filter with f = 100kHz and f = 2MHz, a 3.9MHz, 10mV input will CLK produce a 100kHz, 10mV output. A 1st or 2nd order prefilter will reduce aliasing to acceptable levels in most cases. A GUIDE TO BANDPASS DESIGN Filter design tools like FCAD require design specification ...
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... These errors are due to the 1% resistors used and the side- to-side matching of the LTC1264 f which typically is 0.4%. To adjust for 0dB gain at 40kHz, reduce the value the first stage by 5%. To adjust for a flat passband, adjust by ± ...
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... Order Bandpass and Notch Filters CENTER CLK R1 BANDPASS IN INV B R2 HPB/NB R3 BPB LPB SB 0.1µF LTC1264 AGND + 7. LPA R3 BPA R2 HPA/ NOTCH IN INV A LTC1264 SIDE MODE OUT 1 INV C R2 HPC/NC R3 BPC R4 LPC C SC – V –8V 0.1µF f CLK CLK C SD LPD R4 ...
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... CUTOFF R2 R3 BPC R4 LPC C SC – –7.5V V CLK 0.1µ CLK 2MHz LPD R4 BPD R3 R2 OUT LTC1264 SIDE MODE 27. 23. MAXIMUM f CLK ±7.5V R 3.6MHz (C = 10pF) H ±5V 27.4k 2.0MHz (C = 10pF SINGLE 5V 1.6MHz (C = 10pF) C Gain vs Frequency 10 0 –10 –20 –30 – ...
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... N .325 ±.005 NOTE 3 N .093 – .104 × 45° (2.362 – 2.642) 0° – 8° TYP .050 (1.270) BSC .014 – .019 (0.356 – 0.482) TYP LTC1264 1.280* (32.512) MAX .065 (1 ...
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... Four 2nd Order Filter Sections in 28-Pin SSOP, 200kHz Max Center Frequency, Operation 3.3V to ±5V Four 2nd Order Filter Sections in 28-Pin SSOP, 40kHz Max Center Frequency, 3.5mA at Single 5V, Operation 3.3V to ±5V Four 2nd Order Filter Sections, No Clock Required, 150kHz Max Center Frequency, SSOP www.linear.com ● LTC1264 SIDE MODE 3a 3 ...