微型脉搏表中低功耗电路的设计

The Design of Low Power Consumption Circuit in the Minitype Pulse Watch

便携式测量仪器的设计通常需要考虑功耗问题 ,微型脉搏表的设计也是如此。文中介绍了微型脉搏表的工作流程 ,并给出了降低能耗的方法。通过脉冲驱动发光二极管发光、模拟开关控制放大器的工作状态 ,降低了电路的工作能耗。由于采用脉冲驱动二极管发光 ,就要解决单片机 A/D转换电路的采样和脉冲驱动发光同步的问题 ,论文对脉冲驱动的模拟电路进行了特殊的改进——将模拟电路放大的脉冲信号经过采样保持 ,进行平滑处理 ,最后在 A/D芯片的输入端得到连续信号 ,解决了同步问题。经过实际使用 。

The problems of low power consumptions of portable devices are always considered in design. The design of minitype pulse watch also has it. In this paper, the work procedure of the pulse watch is introduced, and the ways of reducing the power consumption are presented too. By using the pulse generator to drive light emitting diode (LED), and the analog switcher to control the amplifiers, the circuit remarkably reduces its power consumptions. At the same time, in order to solve the problem of synchronization between the sampling frequency of A/D converter and the frequency of pulse that drive LED, the signal has been smoothed by a S/H circuit before it was sampled by microprocessor. So that the signal input to the A/D chip is an continuous signal, the synchronization is not important any more. During the practical use, the system had attained the satisfaction result in the low power consumption and easy controlling.