一种简单数字测温电路的设计-河北工业科技-河北科技大学.pdf

25 1 河 北 工 业 科 技 V ol . 25, No . 1 200 8 1 H ebei J our nal of Indu str ial Science and T echno log y J an . 2008 1008- 1534( 2008) 0 1-0039- 04 , , ( 河北科技大学电气信息学院, 河北石家庄 050018) 针对生产试验中低成本高精度的需 , 利用 8 位 A/ D 转换芯片 T LC54 9单片机 A T 89 C2051放大器A D626 和数码驱动芯片74H C595 设计测温电路电路中利用对桥电阻的合 理选择改善桥的线性关系理论分析和实际电路测试结果表明, 该电路具有精度高可靠性高使 用方便等优点 测温电路; 线性处理; A D626 ; T LC549 T N709 A A sim ple design of t he digit al t em perature m easurem ent circu it ZH A N G Jiang- t ao, W U X ue- li, M EN G H ua ( Colleg e of Electrical Eng ineering and Inf o rm atio n Science, Hebei U niver sity of Science and T echnolog y, Shij iazhuang H ebei 050018, China) Abstract: T o m eet the need f o r a temper ature m easurem ent circu it w ith low co st and hig h accuracy, the design is m ade w it h an A/ D conver tor T LC54 9 of eight bit s, a sing le chip m icro computer A T 89C2051, an amplif ier A D626 and a L E D drive chip 74 H C595 ar e needed . T he selection of prop er bridg e r esistance adv ances t he non- linear izat ion of the bridg e- circu it . T he real cir- cu it is easy t o implem ent , and the test r esult sho w s it s hig h pr ecision , r eliabilit y, and co nv onience in u se. Key words: temper atur e m easurem ent cir cu it ; linear processing; AD626 ; T LC54 9 , , A T 89C2051 1 1. 1 Cu 100 - , , [ 1~ 6] , 1 , R 1, R 2 , R x , R3 = R 3/ / W1 , A/ D T L C549