LTC2412IGN Linear Technology, LTC2412IGN Datasheet
LTC2412IGN
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LTC2412IGN Summary of contents
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... The LTC2412 communicates through a flexible 3-wire digital interface which is compatible with SPI and MICROWIRE , LTC and LT are registered trademarks of Linear Technology Corporation. No Latency is a trademark of Linear Technology Corporation. MICROWIRE is a trademark of National Semiconductor Corporation. ...
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... REF = GND 2.5V INCM – = GND 1.25V, (Note 6) INCM + – 5.5V, REF = 5V, REF = GND, – (Note 13 ORDER PART NUMBER TOP VIEW 16 GND LTC2412CGN 15 GND LTC2412IGN SCK 12 SDO PART MARKING 10 GND 9 GND 2412 2412I GN PACKAGE = 125 C, = 110 C/W JA MIN TYP MAX ...
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U CO VERTER CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS Input Common Mode Rejection DC 2.5V REF GND IN Input Common Mode Rejection 2.5V REF 60Hz 2% GND IN Input Common Mode Rejection 2.5V REF 50Hz 2% ...
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LTC2412 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 CS Low Level Input Voltage IL CS High ...
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CHARACTERISTICS range, otherwise specifications are SYMBOL PARAMETER f External Oscillator Frequency Range EOSC t External Oscillator High Period HEO t External Oscillator Low Period LEO t Conversion Time CONV f Internal SCK ...
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LTC2412 W U TYPICAL PERFOR A CE CHARACTERISTICS Total Unadjusted Error vs Temperature ( 5V) REF 1.5 1.0 0 –0.5 + REF = 5V T ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Noise Histogram (Output Rate = 7.5Hz 5V 2.5V) CC REF 12 10,000 CONSECUTIVE GAUSSIAN READINGS DISTRIBUTION 0.033ppm 2.5V = 0.293ppm ...
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LTC2412 W U TYPICAL PERFOR A CE CHARACTERISTICS RMS Noise vs V INCM 850 825 800 775 750 + REF = 5V – REF = GND 725 REF + INCM ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS + Full-Scale Error REF = 2.5V – REF = GND – 2.5V REF + IN = 1.25V – GND –2 F ...
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LTC2412 W U TYPICAL PERFOR A CE CHARACTERISTICS Conversion Current vs Temperature 240 V = 5.5V 230 CC 220 210 F = GND GND 200 SCK = NC SDO = NC 190 180 ...
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CTIO S F (Pin 14): Frequency Control Pin. Digital input that O controls the ADC’s notch frequencies and conversion time. When the F pin is connected converter uses its internal oscillator and ...
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LTC2412 U U APPLICATIO S I FOR ATIO CONVERTER OPERATION Converter Operation Cycle The LTC2412 is a low power, alternate channel selection between the two differential channels and an easy-to-use 3-wire serial interface (see Figure 1). Channel 0 is selected ...
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U U APPLICATIO S I FOR ATIO The LTC2412 performs offset and full-scale calibrations every conversion cycle. This calibration is transparent to the user and has no effect on the cyclic operation de- scribed above. The advantage of continuous calibration ...
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LTC2412 U U APPLICATIO S I FOR ATIO Bit 31 (first output bit) is the end of conversion (EOC) indicator. This bit is available at the SDO pin during the conversion and sleep states whenever the CS pin is LOW. ...
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U U APPLICATIO S I FOR ATIO Table 2. LTC2412 Output Data Format Differential Input Voltage 0.5 • REF 0.5 • – 1LSB REF 0.25 • REF 0.25 ...
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LTC2412 U U APPLICATIO S I FOR ATIO outside specifications but the following conversions will not be affected. If the change occurs during the data output state and the converter is in the Internal SCK mode, the serial clock duty ...
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U U APPLICATIO S I FOR ATIO anytime a LOW-to-HIGH transition is detected at the CS pin after the converter has entered the data output state (i.e., after the first rising edge of SCK occurs with CS = LOW). Finally, ...
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LTC2412 U U APPLICATIO S I FOR ATIO The serial data output pin (SDO) is Hi-Z as long HIGH. At any time during the conversion cycle, CS may be pulled LOW in order to monitor the state ...
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U U APPLICATIO S I FOR ATIO CS SDO SCK (EXTERNAL) CONVERSION Figure 7. External Serial Clock Operation (2-Wire) typically 1ms after V exceeds 2V. The level applied to CC SCK at this time determines if SCK ...
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LTC2412 U U APPLICATIO S I FOR ATIO <t EOCtest CS SDO Hi-Z Hi-Z SCK (INTERNAL) CONVERSION SLEEP SLEEP TEST EOC (OPTIONAL) device returns to the sleep state and the conversion result is held in the internal static shift register. ...
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U U APPLICATIO S I FOR ATIO > t EOCtest CS TEST EOC BIT 0 SDO EOC Hi-Z Hi-Z Hi-Z SCK (INTERNAL) SLEEP CONVERSION SLEEP DATA OUTPUT Figure 9. Internal Serial Clock, Reduced Data Output Length internal pull-up may not ...
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LTC2412 U U APPLICATIO S I FOR ATIO CS BIT 31 SDO EOC CH0/CH1 SCK (INTERNAL) CONVERSION PRESERVING THE CONVERTER ACCURACY The LTC2412 is designed to reduce as much as possible the conversion result sensitivity to device decoupling, PCB layout, ...
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U U APPLICATIO S I FOR ATIO Parallel termination near the LTC2412 pin will eliminate this problem but will increase the driver power dissipation. A series resistor between 27 and 56 placed near the driver or near the LTC2412 pin ...
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LTC2412 U U APPLICATIO S I FOR ATIO For a simple approximation, the source impedance R + – driving an analog input pin ( considered to form, together with R Figure 11), a first order passive network with ...
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U U APPLICATIO S I FOR ATIO of input multiplexers, wires, connectors or sensors, the LTC2412 can maintain its exceptional accuracy while operating with relative large values of source resistance as shown in Figures 13 and 14. These measured results ...
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LTC2412 U U APPLICATIO S I FOR ATIO 120 100 REF = 5V A – REF = GND 80 + – INCM ...
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U U APPLICATIO S I FOR ATIO REF = 5V – REF = GND – – 2. GND O – –30 ...
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LTC2412 U U APPLICATIO S I FOR ATIO 1000 12 SOURCE 500 SOURCE – 100 SOURCE –6 –9 –12 –15 –0.5 –0.4–0.3–0.2–0.1 0 0.1 0.2 0.3 0.4 0.5 V ...
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U U APPLICATIO S I FOR ATIO 500 450 REF = 5V – REF = GND 400 V = 2.5V INCM 350 EXTERNAL OSCILLATOR O 300 250 T = ...
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LTC2412 U U APPLICATIO S I FOR ATIO REF 2.5V REF – REF = GND 2.5V INCM ...
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U U APPLICATIO S I FOR ATIO input driving amplifier. This bandwidth includes the band limiting effects of the ADC internal calibration and filtering. The noise of the driving amplifier referred to the converter input and including all these effects ...
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LTC2412 U U APPLICATIO S I FOR ATIO Figure 36 (rejection 256f ) where notch frequency. These curves have been derived for the external oscillator mode but they can be used in all operating ...
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U U APPLICATIO S I FOR ATIO of full scale. In many industrial applications not un- common to have to measure microvolt level signals super- imposed over volt level perturbations and LTC2412 is eminently suited for such tasks. ...
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LTC2412 U U APPLICATIO S I FOR ATIO 0 –20 –40 – 60 –80 –100 –120 0 15 Figure 39. Measured Input Normal Mode Rejection vs Input Frequency with Input Perturbation of 150% Full Scale (60Hz Notch) 0 –20 –40 ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...
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... Noise, 8ppm INL, Pin Compatible with LTC2404/LTC2408 4kHz Output Rate, 200nV Noise, 24.6 ENOBs www.linear.com SELECTED FOR 60Hz REJECTION 13 SCK 12 SDO 11 CS 2412 TA05 Noise P-P Noise, 2ppm INL RMS Noise RMS LT/TP 1202 2K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2002 2412f ...