LTC1742 LINER [Linear Technology], LTC1742 Datasheet
LTC1742
Related parts for LTC1742
LTC1742 Summary of contents
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... Pin selectable input ranges of 1V and 1.6V along with a resistor programmable mode allow the LTC1742’s input range to be optimized for a wide variety of applications. The LTC1742 is perfect for demanding communications applications with AC performance that includes 76.5dB SNR and 90dB spurious free dynamic range ...
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... Digital Output Voltage ................. – 0. OGND Voltage ..............................................– 0. Power Dissipation ............................................ 2000mW Operating Temperature Range LTC1742C ............................................... LTC1742I ............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 VERTER CHARACTERISTICS temperature range, otherwise specifications are at T ...
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... Input Signal, First 5 Harmonics (3.2V Range 2.52MHz 5.2MHz (2V Range) IN1 IN2 f = 2.52MHz 5.2MHz (3.2V Range) IN1 IN2 SOURCE (Note 5) CONDITIONS OUT OUT 4.75V V 5.25V DD 1mA I 1mA OUT LTC1742 MIN TYP MAX UNITS 72 76 76.5 dB 72 ...
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... LTC1742 U U DIGITAL I PUTS A D DIGITAL OUTPUTS operating temperature range, otherwise specifications are at T SYMBOL PARAMETER V High Level Input Voltage IH V Low Level Input Voltage IL I Digital Input Current IN C Digital Input Capacitance IN V High Level Output Voltage OH V Low Level Output Voltage ...
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... FREQUENCY (MHz) LTC1742 = 5V 65MHz, differential ENC/ENC = 2V SAMPLE 8192 Point FFT, Input Frequency = 15MHz, –1dB, 3.2V Range –10 –20 –30 –40 –50 –60 –70 –80 – ...
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... LTC1742 W U TYPICAL PERFOR A CE CHARACTERISTICS 8192 Point FFT, Input Frequency = 30MHz, –10dB, 3.2V Range –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 FREQUENCY (MHz) 1742 G07 8192 Point FFT, Input Frequency = 40MHz, – ...
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... INPUT LEVEL (dBFS) 1742 G23 LTC1742 8192 Point 2-Tone FFT, Input Frequency = 5MHz and 7MHz, –7dB, 3.2V Range –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 – ...
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... LTC1742 W U TYPICAL PERFOR A CE CHARACTERISTICS SFDR vs Input Frequency and Amplitude, 3.2V Range, 2nd and 3rd Harmonic 100 –20dB 95 –10dB 90 –6dB 85 80 –1dB 100 60 INPUT FREQUENCY (MHz) 1742 G25 SNR vs Input Frequency 3.2V and 2V Range 77.0 76.5 76.0 75.5 75.0 74.5 74.0 73.5 73.0 72.5 72.0 71 ...
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... Positive Supply for the Output Driv- DD ers. Bypass to ground with 0.1 F ceramic chip capacitor. D4-D6 (Pins 33 to 35): Digital Outputs. D7-D10 (Pins 39 to 42): Digital Outputs. D11-D13 (Pins 44 to 46): Digital Outputs. OF (Pin 48): Over/Under Flow Output. High when an over or under flow has occurred. LTC1742 1742f 9 ...
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... LTC1742 DIAGRA • N ANALOG INPUT t 3 ENC t 7 DATA t 6 CLKOUT DATA U U APPLICATIO S I FOR ATIO DYNAMIC PERFORMANCE Signal-to-Noise Plus Distortion Ratio The signal-to-noise plus distortion ratio [S/(N + D)] is the ratio between the RMS amplitude of the fundamental input frequency and the RMS amplitude of all other frequency components at the ADC output ...
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... The encode input is also differential for improved common mode noise immunity. The LTC1742 has two phases of operation, determined by the state of the differential ENC/ENC input pins. For brev- ity, the text will refer to ENC greater than ENC as ENC high and ENC less than ENC as ENC low ...
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... SAMPLE/HOLD OPERATION AND INPUT DRIVE Sample/Hold Operation Figure 2 shows an equivalent circuit for the LTC1742 CMOS differential sample-and-hold. The differential ana- log inputs are sampled directly onto sampling capacitors (C ) through CMOS transmission gates ...
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... Poor matching will result in higher even order harmonics, especially the second. Input Drive Circuits Figure 3 shows the LTC1742 being driven transformer with a center tapped secondary. The second- ary center tap is DC biased with V CM signal at its optimum DC level ...
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... See the Typical Performance Charac- teristics section. Driving the Encode Inputs The noise performance of the LTC1742 can depend on the encode signal quality as much as on the analog input. The ENC/ENC inputs are intended to be driven differentially, primarily for noise immunity from common mode noise sources ...
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... DD single-ended drive. Maximum and Minimum Encode Rates The maximum encode rate for the LTC1742 is 65Msps. For the ADC to operate properly the encode signal should have a 50% ( 5%) duty cycle. Each half cycle must have at least 7.3ns for the ADC internal circuitry to have enough settling time for proper operation ...
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... APPLICATIO S I FOR ATIO At sample rates slower than 65Msps the duty cycle can vary from 50% as long as each half cycle is at least 7.3ns. The lower limit of the LTC1742 sample rate is determined by droop of the sample-and-hold circuits. The pipelined architecture of this ADC relies on storing analog signals on small valued capacitors ...
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... ADC OGND (Pin 38). HEAT TRANSFER Most of the heat generated by the LTC1742 is transferred from the die through the package leads onto the printed circuit board. In particular, ground pins 12, 13, 36 and 37 are fused to the die attach pad. These pins have the lowest thermal resistance between the die and the outside envi- ronment ...
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... LTC1742 U U APPLICATIO S I FOR ATIO 1742f ...
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... 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights Layer 4 Solder Side LTC1742 Layer 1 Component Side Layer 3 Power Plane 19 1742f ...
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... Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Pin Compatible with the LTC1742 Rail-to-Rail Input and Output www.linear.com 7.9 – ...