CS5560-ISZR Cirrus Logic Inc, CS5560-ISZR Datasheet
CS5560-ISZR
Specifications of CS5560-ISZR
Related parts for CS5560-ISZR
CS5560-ISZR Summary of contents
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Multiplexing the CS556x/7x/8x Delta-Sigma ADCs 1. INTRODUCTION The CS556x/7x/8x devices represent a new generation of delta-sigma analog-to-digital converters that compete with SAR (successive approximation register) converters, with some distinct advantages. The unique features of these over-sampling converters allow them to ...
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... AIN4 Figure 2. Amplifier and Filter between Multiplexer and ADC With high-throughput converters like the 50 kSps CS5560/61, 100 kSps CS5570/71, or the 200 kSps CS5580/81 the circuit must settle in less than 10 MCLK periods (625 nanoseconds). The multiplexer before a SAR converter can be switched to the next channel after the conversion begins since the signal has already been sampled. How- ever, many SAR ADC data sheets warn that a certain " ...
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AIN1 AIN2 AIN3 AIN4 Figure 4. Amplifier(s) and Filter(s) Placed Before Multiplexer As illustrated, not every input may require an amplifier or buffer. This is because there is an on-chip buffer in the CS556x/7x/8x. This rough charge buffer minimizes the ...
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If an op-amp or high-impedance source is used for the input to the MUX, there could be an issue with settling ...
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... This is because the full-scale input range of the differ- ential input devices is twice that of the single ended devices. For example the CS5560/70/80 has a differential input range of 8.192 volts (±4.096) while the CS5561/71/81 has a full-scale input range of 4.096 volts (±2.048). For an equivalent internal noise, this means the full-scale input-to-noise ratio improves when using the differential input devices ...
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SELECTING AN AMPLIFIER If an amplifier is needed to change the full-scale range or to buffer the inputs and it is placed between the MUX and the ADC, one of the most critical parameters will be settling time. However, ...
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... Figure 6. 2-input, Single-ended-to-differential, Multiple Input Range, Multiplexed System In Figure 6, the differential device, CS5560, is multiplexed between two inputs which use single-ended-to-differential conversion circuits. As illustrated, each of these circuits can be configured to attenuate or amplify the single-ended input signal to use the full-scale range of the converter which is differentially ±4.096V optional capacitor which can be used to attenuate out-of-band noise to improve overall noise performance ...
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Figure 7. 8-input, Single-ended, Multiple Input Range, Multiplexed System The circuit shown in Figure 7 is similar to the differential circuit except there is no need to convert the single-ended input signal to differential. As mentioned previously, there will be ...
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CONCLUSION The CS556x/7x/8x family of devices offers an exceptional alternative to SAR devices in multiplexed applications. Due to their digital filter with single-conversion settling, the input to the ADC can change from one end of full scale to the ...
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REVISION HISTORY Release Date REV1 AUG 2007 Initial Release Contacting Cirrus Logic Support For all product questions and inquiries, contact a Cirrus Logic Sales Representative. To find the one nearest to you IMPORTANT NOTICE Cirrus Logic, Inc. and ...