Patent ID: 7403144

Claim:
A circuit for solving a first order linear ordinary differential equation comprising: a second order unit element encoder circuit; and a time decoder circuit coupled in series to the second order unit element encoder circuit, wherein the second order unit element encoder circuit includes: an input amplifier responsive to an input signal and providing an amplified output signal; a first 1-bit digital to analog converter having a first 1-bit digital to analog converter input and a first 1-bit digital to analog converter output; a first adder having a first adder first input responsive to the amplified output signal and a first adder second input responsive to an output signal from the first 1-bit digital to analog converter to provide a first sum output signal; a first integrator responsive to the first sum output signal and providing a first integrated output signal; a second 1-bit digital to analog converter having a second 1-bit digital to analog converter input and a second 1-bit digital to analog converter output; a second adder having a second adder first input responsive to the first integrated signal and a second adder second input responsive to an output signal from the second 1-bit digital to analog converter signal to provide a second sum signal; a second integrator responsive to the second sum signal and providing a second integrated output signal; and a hysteresis quantizer responsive to the second integrated output signal and providing a time encoded pulse output signal corresponding to a time encoding of a solution of the first order linear ordinary differential equation, wherein the first 1-bit digital to analog converter is responsive to the time encoded pulse output signal and feeds back the time encoded pulse output signal to the first adder second input, wherein the second 1-bit digital to analog converter is responsive to the time encoded pulse output signal and feeds back the time encoded pulse output signal to the second adder input, and wherein the time decoder circuit is responsive to the time encoded pulse output signal and is adapted to recover the solution of the first order linear ordinary differential equation from the time encoded pulse output signal.