Apparatus and method for implementing an analog-to-digital converter in programmable logic devices
AssigneeAtmel Corporation
InventorOliver C. Kao
Life of this patent
Estimating the term…
Abstract
An apparatus and method for providing an analog-to-digital converter (ADC) in programmable logic devices is disclosed. A plurality of multi-purpose input/output (I/O) blocks is configured to provide analog-to-digital conversion and other I/O functionality. The plurality of multi-purpose I/O blocks is also configured to save power when ADC mode is disabled.
Claims18
An apparatus for providing an analog-to-digital converter (ADC) in a programmable logic device (PLD) comprising:
- a plurality of input/output (I/O) blocks having a plurality of switching circuits and a plurality of comparators, wherein the plurality of I/O blocks provide the ADC;
- a sample and hold circuit coupled to the plurality of I/O blocks providing an analog input signal;
- a programming signal for selectively switching the plurality of switching circuits to provide the analog input signal to the plurality of comparators;
- a resistor network coupled to the plurality of switching circuits and comparators providing a first plurality of reference voltage signals, the plurality of comparators comparing the analog input signal to the first plurality of reference voltage signals and providing a plurality of discrete digital values;
- an encoder for converting the plurality of discrete digital values to a plurality of M bit digital values and providing the M bit digital values to the PLD for processing, and
- wherein the plurality of I/O blocks provide I/O functionality while an ADC mode is enabled in the plurality of I/O blocks.
A method for providing an analog-to-digital converter (ADC) in a programmable logic device (PLD) having a plurality of input/output (I/O) blocks, the method comprising:
- initializing programmable logic fuses;
- detecting switching values to determine if an ADC mode is desired;
- inputting an analog signal;
- providing a first plurality of reference voltage signals by a resistor network for producing a plurality of discrete digital values representing a voltage range of the analog input signal;
- producing a plurality of digital values corresponding to the plurality of discrete digital values;
- and
- providing I/O functionality while the ADC mode is enabled in the plurality of I/O blocks.
A machine readable storage medium having a stored set of instructions executable by a machine for an analog-to-digital converter (ADC) in a programmable logic device (PLD) having a plurality of input/output (I/O) blocks, the instructions comprising:
- instructions to initialize programmable logic fuses;
- instructions to detect switch values to determine if an ADC mode is desired;
- instructions to input an analog signal;
- instructions to provide a first plurality of reference voltage signals by a resistor network for producing a plurality of discrete digital values representing a voltage range of the analog input signal;
- instructions to produce a plurality of digital values corresponding to the plurality of discrete digital values;
- and
- instructions to provide I/O functionality while the ADC mode is enabled in the plurality of I/O blocks.
Dependencies are inferred from the claim text.