用热敏电阻，加三个精密电阻搭成惠斯通电桥，当温度变化时电桥会输出差分电压，把输出的电压接在10倍的放大器上，放大器用OP07运放做，放大后接在ICL7107上，然后和单片机进行并行通信，把采集的数字信号进行比例处理，通过数码管显示出来，随便用个单片机就行了，89S51就搞定，数码管用动态扫描显示，到网上查一下动态扫描的驱动方式，很简单的。
benxiongchiln ：把你的答案纠正一下：7107显示的是电压值，并不代表温度值，你是不是弄错了？
温度传感器可以选用ds18b20
我把电路图发上来了这是程序，希望对你有用
#include?<reg52.h>
#define?uchar?unsigned?char
#define?uint?unsigned?int
sbit?DS=P2^2;//define?interface
uint?temp;?//?variable?of?temperature
uchar?flag1;//?sign?of?the?result?positive?or?negative
sbit?dula=P2^6;
sbit?wela=P2^7;
unsigned?char?code?table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,
0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
unsigned?char?code?table1[]={0xbf,0x86,0xdb,0xcf,0xe6,0xed,0xfd,
0x87,0xff,0xef};
void?delay(uint?count)?//delay
{
uint?i; while(count) {i=200;
while(i>0)
i--;
count--;
}}?
///////功能:串口初始化,波特率9600，方式1///////
void?Init_Com(void)
{
TMOD?=?0x20; PCON?=?0x00; SCON?=?0x50; TH1?=?0xFd; TL1?=?0xFd; TR1?=?1;}
void?dsreset(void)//send?reset?and?initialization?command
{
uint?i; DS=0; i=103; while(i>0)i--; DS=1; i=4; while(i>0)i--;}
bit?tmpreadbit(void)//read?a?bit
{
uint?i;
bit?dat;
DS=0;i++;?//i++?for?delay
DS=1;i++;i++;
dat=DS;
i=8;while(i>0)i--;
return?(dat);
}
uchar?tmpread(void)//read?a?byte?date
{
uchar?i,j,dat; dat=0; for(i=1;i<=8;i++) {j=tmpreadbit();
dat=(j<<7)|(dat>>1);//读出的数据最低位在最前面，这样刚好一个字节在DAT里
} return(dat);}
void?tmpwritebyte(uchar?dat)//write?a?byte?to?ds18b20
{
uint?i; uchar?j; bit?testb; for(j=1;j<=8;j++) {testb=dat&0x01;
dat=dat>>1;
if(testb)?//write?1
{
DS=0; i++;i++; DS=1; i=8;while(i>0)i--;}
else
{
DS=0;//write?0 i=8;while(i>0)i--; DS=1; i++;i++;
}
}}
void?tmpchange(void)?//DS18B20?begin?change
{
dsreset(); delay(1); tmpwritebyte(0xcc);?//?address?all?drivers?on?bus tmpwritebyte(0x44);?//?initiates?a?single?temperature?conversion}
uint?tmp()//get?the?temperature
{
float?tt; uchar?a,b; dsreset(); delay(1); tmpwritebyte(0xcc); tmpwritebyte(0xbe); a=tmpread(); b=tmpread(); temp=b; temp<<=8;?//two?byte?compose?a?int?variable temp=temp|a; tt=temp*0.0625; temp=tt*10+0.5; return?temp;}
void?readrom()?//read?the?serial
{
uchar?sn1,sn2; dsreset(); delay(1); tmpwritebyte(0x33); sn1=tmpread(); sn2=tmpread();}
void?delay10ms()//delay
{uchar?a,b;
for(a=10;a>0;a--)
for(b=60;b>0;b--);}
void?display(uint?temp)//显示程序
{
uchar?A1,A2,A2t,A3,ser;
ser=temp/10;
SBUF=ser;
A1=temp/100;
A2t=temp%100;
A2=A2t/10;
A3=A2t%10;
dula=0;
P0=table[A1];?//显示百位
dula=1;
dula=0;
wela=0;
P0=0x7e;
wela=1;
wela=0;
delay(1);
dula=0;
P0=table1[A2];?//显示十位
dula=1;
dula=0;
wela=0;
P0=0x7d;
wela=1;
wela=0;
delay(1);
P0=table[A3];?//显示个位
dula=1;
dula=0;
P0=0x7b;
wela=1;
wela=0;
delay(1);
}
void?main()
{
uchar?a; Init_Com(); do { tmpchange(); //?delay(200); for(a=10;a>0;a--) {
display(tmp());
} }while(1);}
