Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsData collecting ICsData acquisition IC - DA converter (DAC) QFN 68 Exposed Pad

MAX5895

ter is located after the modulator. In the 8x interpolation

mode, the last filter (FIR3) can be configured as low-

pass or highpass (bit 5, address 01h) to select the

lower or upper sideband from the modulation output.

The frequency responses of these three filters are plot-

ted in Figures 5–8.

The programmable interpolation filters multiply the

MAX5895 input data rate by a factor of 2x, 4x, or 8x to

separate the reconstructed waveform spectrum and the

DAC image. The original spectral images, appearing at

around multiples of the input data rate, are attenuated

by the internal digital filters. This feature provides three

benefits:

1) Image separation reduces complexity of analog

reconstruction filters.

2) Lower input data rates eliminate board-level high-

speed data transmission.

16-Bit, 500Msps Interpolating and Modulating

Dual DAC with CMOS Inputs

20 ______________________________________________________________________________________

Figure 9. Spectral Representation of Interpolating Filter Responses (Output Frequencies are Relative to the Data Input Frequency, f

)

FILTER

RESPONSE

FILTER

RESPONSE

FILTER

RESPONSE

INPUT

SPECTRUM

AND FIRST

FILTER

RESPONSE

OUTPUT

SPECTRUM

OF THE

FIRST

FILTER

INPUT

SPECTRUM

AND

SECOND

FILTER

RESPONSE

OUTPUT

SPECTRUM

OF THE

SECOND

FILTER

INPUT

SPECTRUM

AND THIRD

FILTER

RESPONSE

OUTPUT

SPECTRUM

OF THE

THIRD

FILTER

2x INTERPOLATION

4x INTERPOLATION

8x INTERPOLATION

NO INTERPOLATION

SIGNAL

IMAGE

SIGNAL

IMAGE

SIGNAL

IMAGE

SIGNAL

IMAGE