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What is the decimation factor of a digital filter?
The digital filter’s user-selectable decimation factor offers flexibility as conversion resolution can be reduced in exchange for a higher data rate or vice versa. The integrated digital lowpass filter is a first-order or third-order Sinc infinite impulse response filter.
What is the optimum decimation factor for 2 kHz?
Next let’s partition our decimation problem into two stages: with D = 100 and F = (0.2 kHz/2 kHz), Eq. (10-2) yields an optimum D1,opt decimation factor of 31.9. The closest integer submultiple of 100 to 31.9 is 25, so we set D1 = 25 and D2 = 4 as shown in Figure 10-3 (b).
What is the max1402 decimation filter used for?
The MAX1402 can provide 16-bit accuracy at 480 samples per second and 12-bit accuracy at 4,800 samples per second. The chip finds wide application in sensors and instrumentation. The MAX1402 data sheet contains detailed figure information (Maxim Integrated Products, 2007).
Is the first stage of a decimation filter stable?
The combined effect of the first stage is a coarse lowpass filtering with an attenuation of aliasing into the passband of at least 96 dB. A major problem with this approach is that the accumulators have poles at z = 1, i. e., they are marginally stable.
How is a decimation filter used in a switched capacitor?
Then the difference is sent to the discrete-time analog integrator, which is implemented by the switched-capacitor technique, for example. The output from the discrete-time analog integrator is converted using an m-bit ADC to produce the oversampled digital signal. Finally, the decimation filter removes outband quantization noise.
What is the decimation factor of sigma delta ADC?
Functional diagram for the sigma-delta ADC. The chip produces a 1-bit data stream, which will be filtered by the integrated digital filter to complete ADC. The digital filter’s user-selectable decimation factor offers flexibility as conversion resolution can be reduced in exchange for a higher data rate or vice versa.
How are filters and decimation accomplished in Cascade?
The filtering and decimation in the first stage is accomplished by connecting up to five accumulators in cascade. The accumulators yield the transfer function where n is the number of accumulators. The accumulators represent first-order recursive filters. Next follows the decimation.