LTC1405 Linear Technology, LTC1405 Datasheet
LTC1405
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LTC1405 Summary of contents
Page 1
... This easy-to-use device includes a high dynamic range sample-and-hold, a precision reference and a PGA input circuit. The LTC1405 has a flexible input circuit that allows full- scale input ranges of 2.048V, 1.024V and 0.512V. The input common mode range is rail-to-rail and a common mode bias voltage is provided for single supply applica- tions ...
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... Digital Output Voltage ........ (V – 0.3V Power Dissipation .............................................. 500mW Operating Temperature Range LTC1405C ............................................... LTC1405I ............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 VERTER CHARACTERISTICS The denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T With Internal 4 ...
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... C. Specifications are guaranteed for both dual supply and single supply A CONDITIONS V = 5.25V 5.25V – 4.75V 4.75V – LTC1405 MIN TYP MAX – 250 0 4.096V – 0.1dBFS single ended input, REF IN MIN TYP MAX 69.0 71.6 68.7 71.3 – 87 – 78.5 – 83 – 77.0 – 89 – ...
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... LTC1405 U U DIGITAL I PUTS AND OUTPUTS temperature range, otherwise specifications are at T operation. (Note 5) SYMBOL PARAMETER I Digital Input Current IN C Digital Input Capacitance IN V High Level Output Voltage OH V Low Level Output Voltage OL I Output Source Current SOURCE I Output Sink Current ...
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... CLK (Pin 26): Conversion Start Signal. This active high signal starts a conversion on its rising edge. OF (Pin 27): Overflow Output. This signal is high when the digital output is 011111111111 or 100000000000. GAIN (Pin 28): Gain Select for Input PGA. 5V selects an input gain selects a gain of 2. LTC1405 ...
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... LTC1405 CTIO AL BLOCK DIAGRA – MODE SELECT SENSE V REF 0V OR – DIAGRA ANALOG INPUT CLK DATA OUTPUT GAIN (PIN 7) (PIN 23) S/H PIPELINED 12-BIT ADC DIGITAL CORRECTION LOGIC 2.5V REFERENCE 2.048V V GND GND GND SS (PIN 6) ...
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... Power Supplies The LTC1405 will operate from either a single 5V or dual 5V supply, making it easy to interface the analog input to single or dual supply systems. The digital output drivers have their own power supply pin (OV from 3V to 5V, allowing direct connection to either digital systems ...
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... For single 5V supply applications it is convenient to connect A V pin. CM Driving the Analog Inputs The differential inputs of the LTC1405 are easy to drive. The inputs may be driven differentially or single-ended – (i. e., the A input is held at a fixed value). The A IN ...
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... IN LTC1405 – 1405 F05 Figure 7. AC Coupling to the LTC1405. Note That the Input Signal Can Almost Always Be Directly Coupled with Better Performance LTC1405 – A COMMENTS IN 0 Best SNR, THD 2.5 Best SINAD, THD for Single Supply 2.5 Worse Noise than Above Case 2 ...
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... If slower op amps are used, more settling time can be provided by increasing the time between conversions. The best choice for an op amp to drive the LTC1405 will depend on the application. Generally applications fall into two categories: AC applications where dynamic specifica- tions are most critical and time domain applications where DC accuracy and settling time are most critical ...
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... Thus output data can be latched on the third CLK rising edge after the rising edge that samples the input. Clock Input The LTC1405 only uses the rising edge of the CLK pin for internal timing, and CLK doesn’t necessarily need to have a 50% duty cycle. For optimal AC performance the rise time of the CLK should be less than 5ns ...
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... Figure 13. Cross Section of LTC1405 Printed Circuit Board connected to this ground plane. All bypass capacitors for the LTC1405 should also be connected to this ground plane (Figure 12). The digital system ground should be connected to the analog ground plane at only one point, is near the OGND pin. ...
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... U U APPLICATIO S I FOR ATIO W U LTC1405 13 ...
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... LTC1405 U U APPLICATIO S I FOR ATIO Figure 15. Top Silkscreen Layer for LTC1405/LTC1420 Demo Board Figure 17. Ground Plane Layer for LTC1405/LTC1420 Demo Board Figure 16. Top Layer for LTC1405/LTC1420 Demo Board Figure 18. Power Plane Layer for LTC1405/LTC1420 Demo Board ...
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... U U APPLICATIO S I FOR ATIO Figure 19. Bottom Layer for LTC1405/LTC1420 Demo Board U TYPICAL APPLICATIO Single Supply, 5Msps, 12-Bit ADC with 3V Logic Outputs 30 ANALOG INPUT (2.5V 1.024V) 1000pF LTC1405 GAIN NPO – CLK 5MHz CLOCK ...
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... COMMENTS Pin Compatible with LTC1405 Best Dynamic Performance, SINAD = 72dB at Nyquist 55mW Power Dissipation, 72dB SINAD 0.05% Max Initial Accuracy, 5ppm/ C Max Drift 1405i LT/TP 0100 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2000 0.033 (0.838) REF 0.150 – ...