LTC2498IUHF#PBF Linear Technology, LTC2498IUHF#PBF Datasheet

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... L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No Latency ∆∑ and Easy Drive are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. 2.7V TO 5.5V V 0.1µ ...

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... LEAD FREE FINISH TAPE AND REEL LTC2498CUHF#PBF LTC2498CUHF#TRPBF LTC2498IUHF#PBF LTC2498IUHF#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...

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T PARAMETER CONDITIONS Negative Full-Scale Error Drift 2.5V ≤ V Total Unadjusted Error 5V ≤ ≤ V 2.7V ≤ V Output Noise 5.5V ...

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LTC2498 analog input anD reFerence temperature range, otherwise specifications are at T SYMBOL PARAMETER – – IN Absolute/Common Mode IN – (IN Corresponds to the Selected Negative Input Channel) V Input Differential Voltage Range ( Full Scale of ...

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Digital inputs anD Digital outputs full operating temperature 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 for 1x Speed ...

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LTC2498 typical perForMance characteristics Integral Nonlinearity ( 5V) CC REF REF 2.5V IN(CM GND O 1 –45°C 25°C 0 85°C –1 –2 –3 ...

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RMS Noise vs Input Differential Voltage 1 REF 0 2.5V IN(CM 25°C A 0.8 0.7 0.6 0.5 0.4 –2.5 –2 –1.5 –1 –0.5 0 0.5 1 ...

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LTC2498 typical perForMance characteristics On-Chip Oscillator Frequency vs Temperature 310 308 306 304 2.5V REF 302 GND IN(CM GND O 300 30 –45 –30 –15 0 ...

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Integral Nonlinearity (2x Speed Mode 5V 2.5V) CC REF 2.5V REF 1.25V IN(CM GND O 1 90°C 0 –1 –45°C, 25°C ...

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LTC2498 typical perForMance characteristics PSRR vs Frequency at V (2x Speed Mode 4.1V DC ±1. REF = 2.5V –20 – REF = GND + IN = GND – – GND f = GND ...

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Functions SDI (Pin 34): Serial Data Input. This pin is used to select the line frequency rejection mode mode, temperature sensor, as well as the input channel. The serial data input is applied under control of ...

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LTC2498 Functional block DiagraM TEMP V SENSOR CC MUXOUTP GND + REF – REF CH0 CH1 • • MUX • CH15 COM MUXOUTN test circuits SDO 1.69k C LOAD Hi ...

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DiagraMs Timing Diagram Using Internal SCK (SCK HIGH with CS↓ SDO t 3 SCK SDI SLEEP Timing Diagram Using External SCK (SCK LOW with CS↓ SDO t 5 SCK SDI SLEEP t KQMIN ...

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LTC2498 applications inForMation CONVERTER OPERATION Converter Operation Cycle The LTC2498 is a multi-channel, low power, delta-sigma analog-to-digital converter with an easy to use 4-wire inter- face and automatic differential input current cancellation. Its operation is made up of three states ...

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This enables external RC networks and high impedance sen- sors to directly interface to the LTC2498 without external amplifiers. The remaining common mode input current is eliminated by either balancing the differential ...

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LTC2498 applications inForMation In order to achieve optimum performance external amplifier is not used, short these pins directly together (ADCINP to MUXOUTP and ADCINN to MUXOUTN) and minimize their capacitance to ground. SERIAL INTERFACE PINS The LTC2498 transmits ...

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Bit 30 (second output bit dummy bit (DMY) and is always LOW. Bit 29 (third output bit) is the conversion result sign indica- tor (SIG). If the selected input (V IN than 0V, this bit is ...

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LTC2498 applications inForMation Table 2. Output Data Format Differential Input Voltage ≥ 0.5 • REF 0.5 • – 1LSB REF 0.25 • REF 0.25 • – ...

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Table 3. Channel Selection MUX ADDRESS ODD/ SGL SIGN ...

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LTC2498 applications inForMation Table 4. Converter Configuration SGL ODD ...

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Slope calibration is not required if the reference volt- age ( known reference has a slope of 314 REF LSBs /°C. The temperature is calculated from the output 24 code (DATAOUT ) for a ...

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LTC2498 applications inForMation External Serial Clock, Single Cycle Operation This timing mode uses an external serial clock to shift out the conversion result and CS to monitor and control the state of the conversion cycle, see Figure 6. The external ...

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Typically, CS remains LOW during the data output/input state. However, the data output state may be aborted by pulling CS HIGH any time between the 1st falling edge and the 32nd falling edge of SCK, see Figure 7. ...

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LTC2498 applications inForMation 10µ SCK (EXTERNAL) SDI DON'T CARE 1 0 EOC “0” SDO BIT 31 BIT 30 CONVERSION SLEEP Figure 8. External Serial Clock, 3-Wire Operation ( progress and EOC = 0 once the ...

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EOCTEST CS 1 SCK (INTERNAL) SDI DON'T CARE 1 SDO EOC BIT 31 CONVERSION SLEEP remains HIGH for the duration of the conversion cycle. Once the conversion is complete, the cycle repeats. Typically, CS remains LOW ...

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LTC2498 applications inForMation <t EOCTEST CS 1 SCK (INTERNAL) SDI DON'T CARE 1 SDO EOC BIT 31 CONVERSION SLEEP Figure 10. Internal Serial Clock, Reduced Data Output Length with Valid Channel and Configuration Selection CS 1 SCK (INTERNAL) DON'T CARE ...

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The input data is shifted through the SDI pin on the ris- ing edge of SCK (including the first rising edge) and the output data is shifted out the SDO pin on the falling edge of SCK. The ...

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LTC2498 applications inForMation Driving the Input and Reference The input and reference pins of the LTC2498 are connected directly to a switched capacitor network. Depending on the relationship between the differential input voltage and the differential reference voltage, these capacitors ...

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This allows direct digitization of high impedance sensors without the need of buffers. The switching algorithm forces the average input current + on the positive input ( equal to the ...

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LTC2498 applications inForMation The LTC6078 is an excellent amplifier for this function. It operates with supply voltages as low as 2.7V and its noise level is 18nV/√Hz. The Easy Drive input technology of the LTC2498 enables an RC network to ...

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1µF , 10µF REF REF + V = 3.75V IN 400 – 1.25V GND 25°C A 300 200 C 100 ...

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LTC2498 applications inForMation to 15dB (see Figure 22), if noise sources are present at these frequencies anti-aliasing will reduce their effects. The user can expect to achieve this level of performance using the internal oscillator, as shown in Figures 23, ...

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Figures 26 and 27 show measurement results for the rejection of a 7.5V peak-to-peak noise source (150% of full scale) applied to the LTC2498. From these curves shown that the rejection performance is maintained even ...

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LTC2498 applications inForMation mode rejection of line frequencies. The common mode rejection of line frequencies remains unchanged, thus fully differential input signals with a high degree of symmetry + – on both the IN and IN pins will continue to ...

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IN(CM) REF(CM EXT CLOCK 25° REF 5 0 – 5V 2.5V CC ...

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LTC2498 package Description 5.50 0.05 4.10 0.05 3.00 REF APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 0.10 PIN 1 TOP MARK (SEE NOTE 6) 7.00 0.10 NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE M0-220 VARIATION WHKD ...

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... Added Note 18 to Digital Inputs and Digital Outputs section 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...

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... Pin Compatible with LTC2498/LTC2449 www.linear.com l SDI ΔΣ ADC SCK WITH EASY DRIVE SDO INPUTS CS 0.1µF 0.1µF 2498 TA02 Noise, 2ppm INL Noise, 4ppm INL, Simultaneous 50Hz/60Hz RMS Noise RMS LT 07/10 REV E • PRINTED IN USA  LINEAR TECHNOLOGY CORPORATION 2006 2498fe ...