前言 ······································································································· 2 2 总体方案设计 ··························································································· 3 2
1 方案论证与比较 ··········································································································· 3 2
2 方案的选择 ··············································································································· 5 3 单元模块设计 ··························································································· 6 3
1 各单元模块功能介绍及电路设计 ······················································································ 6 3
1 秒脉冲发生器 ········································································································ 6 3
