Pulse width modulation driver having programmable current control
AssigneeCaterpillar Inc.
InventorsBrian L. Boggs, Paul C. Gottshall, Steven O. Hart, Brian G. McGee
Life of this patent
Estimating the term…
Abstract
A pulse width modulation driver provides programmable current control for a variety of load current ranges using a modulation feedback block. The block scales a signal representative of a sensed current flowing through the load by a selectable gain multiplier. The scaled signal is compared to a target current value to indicate to a driver control when to generate trigger signals for switching current through the load. In this way, load currents can be amplified to match the operational range of the comparator.
Claims15
A driver for producing a desired pulse width modulated current through a load, comprising:
- a target generator for supplying a target current value;
- a modulation feedback block having
- a gain block for scaling a signal representative of a sensed current flowing through the load by a gain multipliers to generate a plurality of scaled signals, and
- means for selecting one among said sensed and said plurality of scaled signals;
- a comparator for comparing said selected signal to said target current value;
- and
- a driver control for selectively generating trigger signals to switch current through the load in response to the result of said comparison.
A method of producing a desired pulse width modulated current through a load, comprising the steps of:
- scaling a signal representative of a sensed current flowing through the load by a gain multipliers to generate a plurality of scaled signals;
- selecting one signal from among said sensed current and scaled signals;
- supplying a target current value;
- comparing said selected signal to said target current value;
- and
- selectively generating trigger signals to switch current through the load in response to the result of said comparison.
A driver for producing a desired pulse width modulated current through a load, comprising:
- means for supplying a target current value;
- means for scaling a signal representative of a sensed current flowing through the load by a selectable gain multiplier;
- means for comparing said scaled signal to said target current value;
- and
- means for selectively generating trigger signals to switch current through the load in response to the result of said comparison, wherein said scaling means provides a programmable current range over which said current though the load may be switched.
Dependencies are inferred from the claim text.