Counting scheme with automatic point-of-reference generation
AssigneeRamtron International Corporation
InventorsXiao-Hong Du, Craig Taylor
Life of this patent
Estimating the term…
Abstract
A counting scheme for a non-volatile counter includes automatic point-of-reference generation implemented in a state machine. Two state variables are used to store the rotation history of the magnet. One variable stores the previous position of the magnet and the other stores the net angle traveled by the magnet from the reference point. The first pulse location after the counter is reset is automatically selected as the reference point until the next counter reset. When the nonvolatile counter counts up or down, i.e. when the magnet travels 360° in either direction, the second state variable is set to zero and the first state variable is set to the reference point, indicating the start of a new revolution.
Claims21
A counting method for a non-volatile counter comprising:
- choosing a sensor for generating an initial pulse after resetting the counter as a reference for all future counting operations;
- and
- combining the initial sensor pulse, a previous sensor location, and the current sensor location to generate a count value.
A non-volatile monolithic counter comprising:
- first and second independent power sources;
- and
- an automatically detected sensor reference.
A ferroelectric non-volatile counter circuit comprising:
- means for accessing a present count value, adding or subtracting from the count value, and storing a new count value, with only the application of sensor power;
- and
- means for automatically generating a reference for all future counting operations.
A non-volatile counter circuit comprising:
- a state machine;
- and
- an arbitrary point of reference.
A counting scheme for a non-volatile counter with an automatic point-of-reference generation implemented in a state machine comprising:
- using two state variables to store the rotation history of a rotating magnet, wherein a first state variable stores the previous position of the magnet and a second state variable stores the net angle traveled by the magnet from the reference point;
- and
- automatically selecting the first pulse location after the counter is reset as the reference point until the next counter reset.
Dependencies are inferred from the claim text.