LTC2424IG Linear Technology, LTC2424IG Datasheet
LTC2424IG
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LTC2424IG Summary of contents
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... The LTC2424/LTC2428 communicate through a flexible 4-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. 2.7V TO 5.5V ...
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... Operating Temperature Range LTC2424C/LTC2428C .............................. 0.3V 0.3V) LTC2424I/LTC2428I ........................... – 0.3V) Storage Temperature Range ................. – 150 0.3V) Lead Temperature (Soldering, 10 sec).................. 300 ORDER PART NUMBER 1 GND 2 V LTC2424CG SET LTC2424IG 4 ADCIN 5 ZS SET 6 GND 7 MUXOUT CH0 10 CH1 11 CH2 12 CH3 13 CH4 14 CH5 28-LEAD PLASTIC SSOP ...
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U CONVERTER CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER CONDITIONS Total Unadjusted Error V = 2.5V REF REF Output Noise Output Noise (Fast Mode 5V, 100 Samples/Second, f ...
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LTC2424/LTC2428 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 otherwise specifications are (Note 3) A SYMBOL PARAMETER f External Oscillator Frequency Range EOSC t External Oscillator High Period HEO t External Oscillator Low Period LEO t Conversion Time ...
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LTC2424/LTC2428 W U TYPICAL PERFOR A CE CHARACTERISTICS Total Unadjusted Error (3V Supply 2.5V REF –2 – –55 C, – ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS RMS Noise vs Reference Voltage REFERENCE VOLTAGE (V) 24248 G10 Noise Histogram ...
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LTC2424/LTC2428 W U TYPICAL PERFOR A CE CHARACTERISTICS Conversion Current vs Temperature 230 220 V = 5.5V CC 210 200 V = 4.1V CC 190 180 V = 2.7V CC 170 160 150 – 55 –30 – ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS INL vs Output Rate REF F = EXTERNAL – ...
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LTC2424/LTC2428 PIN FUNCTIONS CSADC (Pin 23): ADC Chip Select Input. A low on this pin enables the SDO digital output and following each conver- sion, the ADC automatically enters the Sleep mode and remains in a low ...
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U U APPLICATIONS INFORMATION Converter Operation Cycle The LTC2424/LTC2428 are low power, 4-/8-channel delta- sigma analog-to-digital converters with easy-to-use 4-wire interfaces. Their operation is simple and made up of four states. The converter operation begins with the conversion, followed by ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION Ease of Use The LTC2424/LTC2428 data output has no latency, filter settling or redundant data associated with the conversion cycle. There is a one-to-one correspondence between the conversion and the output data. Therefore, multiplexing an ...
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U U APPLICATIONS INFORMATION The LTC2424/LTC2428 can be interchanged with the LTC2404/LTC2408. The two devices are designed to allow the user to incorporate either device in the same design as long as ZS (Pin 5) of the LTC2424/LTC2428 is tied ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION CSMUX/CSADC SDO Hi-Z SCK/CLK Table 2. LTC2424/LTC2428 Output Data Format Bit 23 Bit 22 Input Voltage EOC DMY V > 9/8 • REF 9/8 • V ...
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U U APPLICATIONS INFORMATION LOW. The multiplexer should be programmed after the previous conversion is complete. In order to guarantee the conversion is complete, the multiplexer addressing should be delayed a minimum t (approximately 133ms for a CONV 60Hz notch) ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION Table 4 summarizes the duration of each state as a function Operation at Higher Data Output Rates The LTC2424/LTC2428 typically operate with an internal oscillator of 153.6kHz. This corresponds to a ...
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U U APPLICATIONS INFORMATION For output data rates samples/second, the total unadjusted error (TUE) is better than 16 bits, and better than 12 bits at 100 samples/second. As shown in Figure 8, for output data rates of ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION 0.20 500ms 0.15 0.10 0.05 0 –0.05 –0.10 –0.15 –0.20 0 0.5 1 1.5 TIME (SEC) Figure 11a. Digitized Waveform 2. 300mV + P-P 2.15 2.10 2.05 2.00 1.95 1.90 ...
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U U APPLICATIONS INFORMATION In the Internal SCK mode of operation, the SCK pin is an output and the LTC2424/LTC2428 creates its own serial clock by dividing the internal conversion clock the External SCK mode of operation, ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION External Serial Clock (SPI/MICROWIRE Compatible) This timing mode uses an external serial clock (SCK) to shift out the conversion result, see Figure 13. This same external clock signal drives the CLK pin in order to ...
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U U APPLICATIONS INFORMATION the 24th rising edge of SCK. On the 24th falling edge of SCK, the device begins a new conversion. SDO goes HIGH (EOC = 1) indicating a conversion is in progress. At the conclusion of the ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION CSADC/ CSMUX SCK/CLK TEST EOC TEST EOC SDO Hi-Z D DON’T CARE Figure 15. External Serial Clock with Reduced Data Output Length Timing Diagram CSMUX t EOCtest CSADC SCKCLK TEST EOC TEST ...
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U U APPLICATIONS INFORMATION In order to select the internal serial clock timing mode, the serial clock pin (SCK) must be floating (Hi-Z) or pulled HIGH prior to the falling edge of CSADC. The device will not enter the internal ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION CSMUX t EOCtest CSADC SCKCLK TEST EOC TEST EOC SDO Hi-Z Hi-Z D DON’T CARE IN Figure 17. Internal Serial Clock with Reduced Data Output Length Timing Diagram A similar situation may occur during the ...
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U U APPLICATIONS INFORMATION While a digital input signal is in the 0. range, the CMOS input receiver draws additional current from the power supply. It should be noted that, when any one of the digital input signals ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION Input Current ( complete settling occurs on the input, conversion re- sults will be unaffected by the dynamic input current. If the settling is incomplete, it does not degrade the linearity performance ...
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U U APPLICATIONS INFORMATION 0 0. 0.001 ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION REF 1000pF VREF 100pF VREF 0.01 F VREF 0 –10 C –20 ...
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U U APPLICATIONS INFORMATION 5V IN OUT + 10 F 0.1 F LT1461-2.5 16V CER TANT GND Figure 30. Low Power Reference than 60% full scale, and only marginally increases noise approaching full scale. Even lower power references can be ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION The LTC2428’s Resolution and Accuracy Allows You to Measure Points in a Ladder of Sensors In many industrial processes, for example, cracking tow- ers in petroleum refineries, a group of temperature mea- surements must be ...
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U U APPLICATIONS INFORMATION Adding gain requires that one of the resistors (PT1 to PT7 precision resistor in order to eliminate the error asso- ciated with the gain setting resistors R2 and R3. Note, that if a precision ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION channel resistance of the multiplexer does not contribute much to the error budget, as only input op amp current flows through the switch. The LTC1050 was chosen for its low input current and offset voltage, ...
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U U APPLICATIONS INFORMATION An 8-Channel DC-to-Daylight Digitizer The circuit in Figure 36 shows an example of the LTC2428’s flexibility in digitizing a number of real-world physical phenomena—from DC voltages to ultraviolet light. All of the examples implement single-ended signal ...
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LTC2424/LTC2428 U U APPLICATIONS INFORMATION could be used to measure the case temperature of the RTD-based thermal power measurement scheme described previously. In general, thermistors yield very good resolu- tion over a limited temperature range. For the half-bridge arrangement shown, ...
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... FLASH SHALL NOT EXCEED 0.254mm (0.010") 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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... SET CC SERIAL DATA LINK MICROWIRE AND 23 CSADC SPI COMPATABLE 20 CSMUX 19, 25 20-BIT CLK + ADC – SDO LTC2428 INTERNAL OSC 26 F SELECTED FOR GND O 60Hz REJECTION 1, 6, 16, 18, 22, 27, 28 24248 F36 24248f LT/TP 0201 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2000 MPU ...