LTC2420 Linear Technology, LTC2420 Datasheet
LTC2420
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LTC2420 Summary of contents
Page 1
... It uses delta-sigma technology and provides a digital filter that settles in a single cycle for multiplexed applications. Through a single pin, the LTC2420 can be configured for better than 110dB rejection at 50Hz or 60Hz 2 can be driven by an external oscillator for a user-defined rejection frequency in the range 1Hz to 800Hz ...
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... Reference Input Voltage to GND .. – 0. Digital Input Voltage to GND ........ – 0. Digital Output Voltage to GND ..... – 0. Operating Temperature Range LTC2420C ............................................... LTC2420I ............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C U CONVERTER CHARACTERISTICS ...
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... I = 1.6mA – 800 A (Note 10 1.6mA (Note 10) O The denotes specifications which apply over the full operating temperature range, CONDITIONS (Note 12 (Note 12) CC LTC2420 MIN TYP MAX UNITS – 0.125 • V 1.125 • V REF REF 0 1.5 pF – 100 ...
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... LTC2420 CHARACTERISTICS range, otherwise specifications are at T 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 Frequency ISCK D Internal SCK Duty Cycle ISCK f External SCK Frequency Range ...
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... W U Output Data Format The LTC2420 serial output data stream is 24 bits long. The first 4 bits represent status information indicating the sign, input range and conversion state. The next 20 bits are the conversion result, MSB first. ...
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... V Operation at Higher Data Output Rates The LTC2420 typically operates with an internal oscillator of 153.6kHz. This corresponds to a notch frequency of 60Hz and an output rate of 7.5 samples/second. The internal oscillator is enabled if the F (logic HIGH for a 50Hz notch possible to drive the F pin with an external oscillator for higher data output rates ...
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... U U APPLICATIO S I FOR ATIO CS BIT 23 BIT 22 SDO EOC Hi-Z SCK 1 SLEEP Table 2. LTC2420 Output Data Format Bit 23 Bit 22 Input Voltage EOC DMY V > 9/8 • REF 9/8 • REF V + 1LSB 0 0 REF REF 3/4V + 1LSB 0 0 REF 3/ REF 1/2V + 1LSB ...
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... At 100 samples/second, the LTC2420 can be used to O capture transient data. This is useful for monitoring set- tling or auto gain ranging in a system. The LTC2420 can monitor signals at an output rate of 100 samples/second. After acquiring 100 samples/second data the F be driven LOW enabling 60Hz rejection to 110dB and the highest possible DC accuracy ...
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... TIME 9c. Digitized Waveform with No Offset Figure 9. Using the LTC2420’s High Accuracy Wide Dynamic Range to Digitize a 300mV P large DC offset. Figures 9a and 9b show the dynamic input performance with a 15Hz signal superimposed P-P level. The same signal with no DC level is shown in Figures 9c and 9d ...
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... The circuit uses an LT single-chip instrumentation amplifier to perform a differ- ential to single-ended conversion. The amplifier’s output voltage is applied to the LTC2420’s input and converted to a digital value with an overall accuracy exceeding 17 bits (0.0008%). Key circuit performance results are shown in Table 3 ...
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... U U APPLICATIO S I FOR ATIO Table 3. Typical Performance of the LTC2420 ADC When Used with the LT1920 Instrumentation Amplifiers in Figure 9’s Differential Digitizing Circuit PARAMETER Differential Input Voltage Range Zero Error Maximum Input Current Nonlinearity Noise (Without Averaging) Noise (Averaged 64 Readings) Resolution (with Averaged Readings) ...
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... LTC2420 U W PACKAGE I FOR ATIO 0.010 – 0.020 (0.254 – 0.508) 0.008 – 0.010 (0.203 – 0.254) 0.016 – 0.050 (0.406 – 1.270) * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" ...