Signal converting apparatus for integrating analog-to-digital converter and digital-to-analog converter and integration unit

Abstract

A signal converting apparatus for integrating an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC) and an integration unit thereof are provided. The present invention integrates ADC and DAC, that do not operate simultaneously, into a signal converting apparatus (SCA), wherein a control signal decides whether an analog-to-digital mode or a digital-to-analog mode is selected. By sharing the operational amplifiers and other components in the SCA, the chip area and the cost are significantly reduced. In addition, in the integration unit, by switching a plurality of capacitor sets with various capacitances, the capacitance coefficients required for switching ADC and DAC are obtained.

1 - 10 . (canceled)  
   
   
       11 . An integration unit, having an input end and an output end; the integration unit comprising: 
 a first capacitor device, for determining the capacitance thereof by a control signal;    a second capacitor device, for determining the capacitance thereof by the control signal;    a first switch, wherein the first end thereof is the input end of the integration unit and the second end thereof is coupled to the first end of the first capacitor device, for connecting the first end and second end thereof during the first period, and disconnecting the first end and second end thereof during the second period;    a second switch, wherein the first end thereof is coupled to the first end of the first capacitor device, and the second end thereof is coupled to a first voltage, for connecting the first end and second end thereof during the second period, and disconnecting the first end and second end thereof during the first period;    a third switch, wherein the first end thereof is coupled to the second end of the first capacitor device, the second end thereof is coupled to a second voltage, for connecting the first end and second end thereof during the first period, and disconnecting the first end and second end thereof during the second period;    a fourth switch, wherein the first end thereof is coupled to the second end of the first capacitor device, and the second end thereof is coupled to the first end of the second capacitor device, for connecting the first end and second end thereof during the second period, and disconnecting the first end and second end thereof during the first period; and    an operational amplifier, wherein the first input end thereof is coupled to the first end of the second capacitor device and the output end thereof is coupled to the second end of the second capacitor device.    
   
   
       12 . The integration unit as recited in  claim 11 , wherein the first capacitor device comprises: 
 a plurality of first control switches, wherein the first end of each first control switch is the first end of the first capacitor device for determining a connection status of the first control switches according to the control signals; and    a plurality of first capacitors, wherein the first end of each first capacitor is coupled to the second end of the corresponding first control switch, respectively, and the second end of each first capacitor is the second end of the first capacitor device.    
   
   
       13 . The integration unit as recited in  claim 11 , wherein the second capacitor device comprises: 
 a plurality of second control switches, wherein the first end of each second control switch is the first end of the second capacitor device for determining a connection status of the second control switches according to the control signals, respectively; and    a plurality of second capacitors, wherein the first end of each second capacitor is coupled to the second end of the corresponding second control switch, respectively, and the second end of each second capacitor is the second end of the second capacitor device.