| 摘要 |
PURPOSE:To attain both arithmetic and D/A conversion functions at one time by controlling the switching timing of respective switches of switched capacitor circuits in response to arithmetic modes and at the same time setting a prescribed reference voltage level in accordance with an arithmetic coefficient set previously. CONSTITUTION:The two pairs of switched capacitor circuits are provided in parallel between a reference voltage generator 70 and an operational amplifier 50. A control circuit 60 controls the switching timing of all switches 20, 21, 30, 31 and 40 of each switched capacitor circuit in response to an arithmetic mode indicating signal. Thus the addition and subtraction terms are actuated in the forward and reverse modes respectively. The multiplication coefficients (a) and (b) select the reference voltage of the generator 70 and vary capacities CA and CB with selection of capacity of a capacity array. Thus it is possible to perform simultaneously both addition/subtraction and D/A conversion operations with addition of coefficients.
|
