Claims
- 1. Analog-to-digital converter (ADC) for converting an in put signal into output code, comprising:
- a source means for providing a reference current;
- a resistive means coupled to the source means and to a reference signal for providing a plurality of comparison signals;
- a comparator/multiplexer means for comparing the comparison signals against ground, selecting one of the comparison signals and producing a code;
- an amplifying means for amplifying the comparison signal selected by the comparator/multiplexer means and providing a signal;
- a switch means for providing the reference signal in response to the input signal and subsequently in response to the amplifying means signal; and
- a digital means for converting a plurality of the codes produced by the comparison/multiplexer means into the output code.
- 2. ADC of claim 1, wherein the amplifying means includes:
- an operational amplifier having an inverting input; and
- a second resistive means for applying the amplifying means signal to the inverting input.
- 3. ADC of claim 1, wherein the switch means includes a sampling means coupled in series with the input signal for sensing the input signal, and storing a momentary value thereof.
- 4. ADC of claim 1, wherein the amplifying means includes a capacitor coupled for storing the comparison signal selected by the comparator/multiplexer.
- 5. ADC of claim 4, wherein the amplifying means includes a second switch means for applying the comparison signal selected by the comparator/multiplexer means to the capacitor.
- 6. ADC of claim 4, wherein the amplifying means includes an operational amplifier having a noninverting input coupled to the capacitor.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of prior application Ser. No. 075,448 filed Jul. 20, 1987, now U.S. Pat. No. 4,857,931.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
75448 |
Jul 1987 |
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