Programmable logic device with specialized multiplier blocks
AssigneeAltera Corporation
InventorMartin Langhammer
Life of this patent
Estimating the term…
Abstract
A specialized multiplier block in a programmable logic device incorporates multipliers and adders, and is configurable as one or more types of finite impulse response (FIR) filter including a Direct Form II FIR filter. The specialized multiplier block further includes input and output registers to allow chaining of Direct Form II FIR filters into longer Direct Form II FIR filters. An output accumulator also allows the specialized multiplier block to operate as a time-division multiplexed FIR filter, performing several filtering operations during each clock cycle of the programmable logic device.
Claims26
A specialized multiplier block for use in a programmable logic device, said specialized multiplier block comprising:
- a plurality of multipliers having multiplier inputs;
- at least one input register chain, at least one input of each of said multipliers being connected to said input register chain;
- a plurality of adders;
- programmable connections between said multipliers and said adders whereby said specialized multiplier block is configurable as a Direct Form II finite impulse response filter;
- and
- an output register for chaining output of said Direct Form II finite impulse response filter to another said specialized multiplier block;
- wherein:
- said specialized multiplier block is configurable with others of said specialized multiplier block as a long Direct Form II finite impulse response filter.
A specialized multiplier block for use in a programmable logic device, said specialized multiplier block comprising:
- a plurality of multipliers having multiplier inputs;
- at least one input register chain, at least one input of each of said multipliers being connected to said input register chain;
- a plurality of adders;
- programmable connections between said multipliers and said adders whereby said specialized multiplier block is configurable as a Direct Form II finite impulse response filter;
- and
- an output accumulator selectably connectable to output of said adders;
- whereby:
- said specialized multiplier block is configurable as a time-division multiplexed Direct Form II finite impulse response filter.
Dependencies are inferred from the claim text.