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1.1 ÈÈÃôµç×èÆ÷
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PositiveTemperatureCoefficient ¼ò³Æ PTC
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Negative Temperature Coefficient ¼ò³Æ NTC ÈÈÃôµç×è¡£
NTC ÈÈÃôµç×èÆ÷£¬ÊÇÒ»ÖÖÒÔ¹ý¶É½ðÊôÑõ»¯ÎïΪÖ÷ÒªÔ²ÄÁÏ£¬²ÉÓõç×ÓÌմɹ¤ÒÕÖƳɵÄÈÈÃô°ëµ¼ÌåÌÕ´É×é¼þ¡£ÕâÖÖ×é¼þµÄµç×èÖµËæζÈÉý¸ß¶ø½µµÍ£¬ÀûÓÃÕâÒ»ÌØÐÔ¿ÉÖƳɲâΡ¢Î¶Ȳ¹³¥ºÍ¿ØÎÂ×é¼þ£¬ÓÖ¿ÉÒÔÖƳɹ¦ÂÊÐÍ×é¼þ£¬ÒÖÖƵç·µÄÀËÓ¿µçÁ÷¡£
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ϱíÊÇÑ¡Óà NTCÈÈÃôµç×èÆ÷ MF52-502F3950B£¬»ùÓÚ¾«È·µÄR-T ÇúÏߣ¬À´¶ÔζȽøÐо«È·µÄ²âÁ¿¡£
1.2 µç×è£Î¶ȹØϵ
Èç±íA1 Ëùʾ£¬NTC ÈÈÃôµç×èÆ÷ MF52-502F3950B ¸÷ζȵãµÄµç×èÖµ£¬¼´µç×è£Î¶ȹØϵ±í¡£´ÓÌṩµÄµç×è£Î¶ȹØϵ±íÖпÉÒÔ ¿´³ö NTC ÈÈÃôµç×èÆ÷MF52-502F3950BµÄ²âη¶Î§Îª [-55¡æ,125¡æ]£¬Æäµç×èÖµµÄ±ä»¯·¶Î§Îª[250062Ω,242.64Ω]¡£
±íA1MF52-502F3950BËùʾ:
ζÈ(¡æ) |
µç×èÖµ(Ω) |
ζÈ(¡æ) |
µç×èÖµ(Ω) |
ζÈ(¡æ) |
µç×èÖµ(Ω) |
-55 |
250062 |
-54 |
237404 |
-53 |
225239 |
-52 |
213575 |
-51 |
202412 |
-50 |
191750 |
-49 |
181580 |
-48 |
171895 |
-47 |
162684 |
-46 |
153933 |
-45 |
145638 |
-44 |
137753 |
-43 |
130293 |
-42 |
123231 |
-41 |
116550 |
-40 |
110232 |
-39 |
104261 |
-38 |
98621.7 |
-37 |
93295.5 |
-36 |
88267.4 |
-35 |
83521.8 |
-34 |
79043.9 |
-33 |
74819.2 |
-32 |
70833.9 |
-31 |
67074.7 |
-30 |
63529 |
-29 |
60184.6 |
-28 |
57030.2 |
-27 |
54054.7 |
-26 |
51247.9 |
-25 |
48600 |
-24 |
46101.6 |
-23 |
43744 |
-22 |
41519 |
-21 |
39418.8 |
-20 |
37435.9 |
-19 |
35563.5 |
-18 |
33795 |
-17 |
32124.4 |
-16 |
30545.8 |
-15 |
29053.8 |
-14 |
27643.3 |
-13 |
26309.5 |
-12 |
25047.9 |
-11 |
23854.2 |
-10 |
22724.6 |
-9 |
21655.3 |
-8 |
20642.7 |
-7 |
19683.6 |
-6 |
18774.9 |
-5 |
17913.6 |
-4 |
17097.1 |
-3 |
16332.9 |
-2 |
15588.4 |
-1 |
14891.5 |
0 |
14230 |
1 |
13601.9 |
2 |
13005.4 |
3 |
12438.7 |
4 |
11900.1 |
5 |
11388.2 |
6 |
10901.3 |
7 |
10438.3 |
8 |
9997.74 |
9 |
9578.41 |
10 |
9181 |
11 |
8799 |
12 |
8436.83 |
13 |
8091.73 |
14 |
7762.78 |
15 |
7449.16 |
16 |
7150.04 |
17 |
6864.7 |
18 |
6592.4 |
19 |
6332.49 |
20 |
6084.32 |
21 |
5847.31 |
22 |
5620.89 |
23 |
5404.53 |
24 |
5197.72 |
25 |
5000 |
26 |
4810.9 |
27 |
4630.01 |
28 |
4456.93 |
29 |
4291.28 |
30 |
4132.69 |
31 |
3980.83 |
32 |
3835.38 |
33 |
3696.03 |
34 |
3562.49 |
35 |
3434.5 |
36 |
3311.78 |
37 |
3194.1 |
38 |
3081.22 |
39 |
2972.92 |
40 |
2869 |
41 |
2769.24 |
42 |
2673.47 |
43 |
2581.5 |
44 |
2493.17 |
45 |
2408.3 |
46 |
2326.76 |
47 |
2248.38 |
48 |
2173.04 |
49 |
2100.6 |
50 |
2032 |
51 |
1963.92 |
52 |
1899.44 |
53 |
1837.4 |
54 |
1777.68 |
55 |
1720.2 |
56 |
1664.85 |
57 |
1611.54 |
58 |
1560.2 |
59 |
1510.74 |
60 |
1463.08 |
61 |
1417.14 |
62 |
1372.87 |
63 |
1330.18 |
64 |
1289.02 |
65 |
1249.32 |
66 |
1211.03 |
67 |
1174.09 |
ζÈ(¡æ) |
µç×èÖµ(Ω) |
ζÈ(¡æ) |
µç×èÖµ(Ω) |
ζÈ(¡æ) |
µç×èÖµ(Ω) |
68 |
1138.44 |
69 |
1104.04 |
70 |
1070.83 |
71 |
1038.78 |
72 |
1007.82 |
73 |
977.93 |
74 |
949.06 |
75 |
921.17 |
76 |
894.22 |
77 |
868.18 |
78 |
843.02 |
79 |
818.69 |
80 |
795.17 |
81 |
772.43 |
82 |
750.44 |
83 |
729.17 |
84 |
708.6 |
85 |
688.7 |
86 |
669.44 |
87 |
650.8 |
88 |
632.76 |
89 |
615.3 |
90 |
598.39 |
91 |
582.02 |
92 |
566.17 |
93 |
550.81 |
94 |
535.94 |
95 |
521.53 |
96 |
507.57 |
97 |
494.05 |
98 |
480.94 |
99 |
468.23 |
100 |
453.3 |
101 |
443.97 |
102 |
432.38 |
103 |
421.15 |
104 |
410.26 |
105 |
399.69 |
106 |
389.44 |
107 |
379.5 |
108 |
369.85 |
109 |
360.48 |
110 |
351.4 |
111 |
342.57 |
112 |
334.01 |
113 |
325.69 |
114 |
317.62 |
115 |
309.77 |
116 |
302.16 |
117 |
294.76 |
118 |
287.57 |
119 |
280.59 |
120 |
273.8 |
121 |
267.21 |
122 |
260.8 |
123 |
254.58 |
124 |
248.52 |
125 |
242.64 |
|
|
|
|
1.3 ÊýÖµ´¦Àí
ͨ¹ý±í A1 µç×è£Î¶ȹØϵ±í¿ÉÒÔºÜÖ±¹ÛµÄ¿´µ½µç×èµÄ±ä»¯·¶Î§´Ó 242.64Ωµ½ 250062Ω£¬ ÔÚ£55¡æµÄʱºòÆä±íÏÖ³öµÄµç×èÖµÊÇ 125¡æʱËù±íÏֵĵç×èÖµµÄ 1030 ±¶£¬Õâô´óµÄ±ä»¯·¶Î§Ò²ÎªÄ£Êýת»»²âÁ¿´øÀ´ÁËÀ§ÄÑ¡£
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ÈçÉÏͼËùʾ NTC ÈÈÃôµç×è Rv ºÍ²âÁ¿µç×è Rm£¨¾«Ãܵç×裩×é³ÉÒ»¸ö¼òµ¥µÄ´®Áª·Öѹµç·£¬²Î¿¼µçѹVCC_Ref ¾¹ý·Öѹ¿ÉÒԵõ½Ò»¸öµçѹֵËæ×ÅζÈÖµ±ä»¯¶ø±ä»¯µÄÊýÖµ£¬Õâ¸öµçѹµÄ´óС½«·´Ó³³öNTC µç×èµÄ´óС£¬´Ó¶øÒ²¾ÍÊÇÏàӦζÈÖµµÄ·´Ó³¡£ ͨ¹ýÅ·Ä·¶¨ÂÉ¿ÉÒԵõ½Êä³öµçѹֵ Vadc ºÍ NTC µç×èÖµµÄÒ»¸ö¹Øϵ
±í´ïʽ1£º
ÄÇô½ÓÏÂÀ´µÄÊý¾Ý´¦Àí½«»ùÓÚʽÉÏʽչ¿ª£º²é³ö´¦ÀíоƬҲ³ÆÄ£Êýת»»Æ÷ ADC µÄ¾«¶È£¬Æä²Î¿¼µçѹΪ 5V£¬Òò´ËÕâÀï¿ÉÒÔÑ¡Ôñ Vref£½5V¡£¸÷ζȵã¶ÔÓ¦µÄ ADC ת»»ºóµÄÊý×ÖÁ¿¿ÉÒÔ¼ÆËã¡£
±í´ïʽ2.
Dadc £½ 1024*Vadc/5V
½áºÏ±í´ïʽ1ºÍ±í´ïʽ2,¿ÉÒԵóö±í´ïʽ3:
Dadc £½ 1024*Rm/(Rv+Rm)
Èç¹ûÕâÀïÈ¡ ²âÁ¿µç×èRm Ñ¡Ôñ4.7KΩ£¬ÄÇô¿ÉÒÔ¼ÆËã³ö
ÔÚ£ 55¡æʱ Ëù¶ÔÓ¦µÄ Dadc = 1024*1000/(250062+1000) = 4£»
ÔÚ 125¡æʱ Ëù¶ÔÓ¦µÄ Dadc£½ 1024*1000/(242.64+1000)£½ 824¡£
¸ù¾ÝÕâÑùµÄ¶ÔÓ¦¹Øϵ¶ÔÊý¾Ý½øÐÐÔ¤´¦Àí£¬µÃµ½ÈçÏ´¦Àí½á¹ûÈçÏÂÊý¾ÝËùʾ£º
tatic const Int16 NTCTAB2[181] =
{
19,20,21,22,23,24,26,27,29,30,32,34,
36,38,40,42,44,47,49,52,55,57,61,64,
67,71,74,78,82,86,90,95,99,104,109,114,
120,150,156,161,168,172,180,187,194,201,208,215,
222,230,238,247,255,264,272,280,291,302,310,319,
328,338,347,357,367,376,384,395,405,414,424,434,
444,453,464,474,484,494,502,512,522,531,540,551,
560,569,579,586,595,604,613,624,633,642,650,658,
666,673,680,688,696,704,712,719,726,733,741,749,
755,760,767,774,780,785,791,798,804,811,816,821,
827,832,837,842,847,851,856,862,868,873,856,860,
864,868,872,876,879,883,886,890,893,896,899,902,
905,908,911,914,917,919,922,924,927,929,931,934,
936,938,940,942,944,946,947,949,951,953,954,956,
958,959,961,962,964,965,966,968,969,970,971,973,
974
};//4.7K
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1.4 ÏßÐÔ²åÖµ
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