| 摘要 |
PURPOSE:To shorten the holding time and at the same time to maintain a stable output with high accuracy, by comparing the output of a D/A converter with the output of a holding circuit in a sampling mode and applying the output of comparison to the holding circuit. CONSTITUTION:The received data is stored in a memory 3. The data read out of the memory 3 by a CPU2 is converted into analog signals by a D/A converter 4 and supplied to a switch 6 via a comparator 5. The output of the switch 6 is applied to a holding circuit 71. The output signal of the circuit 71 is applied to an input of the other side of the comparator 5 via a switch 9. The output of the comparator 5 functions to eliminate the difference of both input signals and charges quickly a capacitor C1. The output of the circuit 71 is checked whether it is coincident with the memory 3 after an A/D conversion. The switches 6 and 9 work synchronously with each other. It is sufficient if the time to be held covers a circulation of these switches. |
