Hi vivek,
instead of basic DSP books I recommend "Filter Books" which are more based on practical aspects. Example: Taylor, "Electronic Filter Design Handbook" (McGraw Hill).

Since I have a chapter on digital filters from S. Lam at hand I attache it as a pdf file; perhaps it helps.
Regards and good luck
buddypoor

Hello Vivek :
      For decimation filtering for delta-sigma ADCs, R. Jacob Baker's <<CMOS: Mixed-Signal Circuit Design, Second Edition>> is a good book. Many DSP book also have the theory of Sinc and halfband filter.
      For low power consumption:
    1: choose the right order of filter and coefficient.
    2: the logic architecture of filter: topology of pipeline(dff vs latch), how many  adders and multipliers and their bits needed.
    3: arithmetic operation block logic design choice:
        adder: carry ripple/select/look-ahead ... adder?
        multiplier: csa tree , wallace tree, booth encoder, fused multiply-Add......?
    4: transistor circuit map:
        combinational circuit: CMOS logic, CPL, CVSL, clock and power gating....
        DFF/Latch:  Maste-slave dff, pulse latch, TSPC, Strong-ARM DFF,Semidynamic DFF, logic fused dff/latch....
    A very good book for circuit and logic design, Neil H. E. Weste, D. Harris, CMOS VLSI Design: A Circuits and Systems Perspective, 3th Edition, Pearson Education Press.
  Hope helpful!

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Hi,

I have never designed digital filters so far (although I did study a bit of DSP at school). I was looking for a good reference that gives the necessary basics to design practical, power-efficient digital filters. Would anyone be able to recommend some papers? I already have the regular DSP books, but they are not very useful in these things.

Hint: The main application would be decimation filtering for delta-sigma ADCs, and power consumption is naturally critical.

Thanks,
Vivek