Signal driver having selectable aggregate slew rate to compensate for varying process, voltage or temperature conditions
AssigneeTexas Instruments Incorporated
InventorBrian D. Young
Life of this patent
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Abstract
A signal driver having a selectable aggregate slew rate, a method of driving a signal driver and a signal driver incorporating the driver or the method. The driver includes plural partial drivers configured to output signals based on time constants established by corresponding plural time-delay networks associated therewith. The signal driver further includes a slew rate selector coupled to the plural time-delay networks and configured to provide a common signal thereto to cause the plural time-delay networks to achieve target time constants, the target time constants causing the output signals to be generated such that the signal driver achieves the selectable aggregate slew rate.
Claims21
A signal driver having a configurable slew rate, comprising:
- plural partial drivers configured to generate drive signals based on time constants established by corresponding plural time-delay networks associated therewith, the plural time-delay networks comprising a tapped RC delay line;
- and
- a slew rate selector coupled to said plural time-delay networks and configured to provide a common signal thereto to cause said plural time-delay networks to achieve target time constants, said target time constants causing said partial drivers to be generated such that said signal driver achieves said selectable aggregate slew rate, wherein said slew rate selector couples said common signal to a first tap on said tapped RC delay line, said first tap being coupled to an input of a first of said plural partial drivers, said common signal being coupled to a second of said plural partial drivers via a second tap on said tapped RC delay line, whereby said common signal coupled to said second of said plural partial drivers is delayed by delay of said first tap plus delay between said first and second taps.
A signal driver having a configurable slew rate, comprising:
- plural partial drivers configured to generate drive signals based on time constants established by corresponding plural time-delay networks associated therewith;
- a slew rate selector coupled to said plural time-delay networks and configured to provide a common signal thereto to cause said plural time-delay networks to achieve target time constants, said target time constants causing said partial drivers to be generated such that said signal driver achieves said selectable aggregate slew rate,
- wherein said common signal is modified by a feedback loop.
A signal driver system having a signal driver with a selectable aggregate slew rate, comprising:
- plural partial drivers configured to generate drive signals based on time constants established by corresponding plural time-delay networks associated therewith;
- and
- a slew rate selector coupled to said plural time-delay networks and configured to provide a common signal thereto to cause said plural time-delay networks to achieve target time constants, said target time constants causing said partial drivers to be generated such that said signal driver achieves said selectable aggregate slew rate, a first time-delay network of said plural time-delay network including:
- at least one switch,
- at least one capacitor, wherein said capacitor is grounded if said switch is closed, and
- a resistive element coupled to a sensor of a partial driver of said plural partial drivers and also to said at least one capacitor, wherein said resistive element is also coupled to a prior resistive element, each of said target time constants being based on said prior resistive element and a closure state of said switch.
A method of controlling an aggregate slew rate, comprising:
- receiving slew rate control data;
- configuring a target edge rate as a function of said slew rate control data;
- delaying an introduction of a first partial driver as a function of said target time constant;
- and
- delaying an introduction of a second partial driver as a function of both said target edge rate and an introduction of said first signal slice;
- further comprising delaying an output driver signal as a function of said target time constant, said target time constant a function of a resistance of a resistive element and a reactance of a time-delay network associated with said first partial driver, wherein delaying said output driver signal delays said introduction of said first partial driver and adjusting said slew rate control data as a function of a signal received from a feedback loop.
Dependencies are inferred from the claim text.