Ä£Äâµç×Ó¼¼ÊõµÚ4ÕÂϰÌâ´ð°¸ ÏÂÔØ±¾ÎÄ

b1ib1c1e2ib2rbe2?2ib2c2b3ib3rbe3e3R6c3viR1R2 rbe1e1?1ib1R4?3ib3vob2

£¨3£© Ri3?rbe3?(1??3)R6

Ri2?Av??rbe2 1??2vo??1Ri2?2R4//Ri3(1??3)R6 ?virbe1rbe2Ri3??1?2(1??3)R4R6

(1??2)rbe1[R4?rbe3?(1??3)R6]Ri=R1//R2//rbe1

R?rRo=R6//4be3

1??34.36×èÈÝñîºÏ·Å´óµç·ÈçͼÌâ4.36Ëùʾ¡£ÒÑÖªVCC£½12V£¬Rb1£½Rb2£½500k?£¬Rc1£½Rc2

£½3k?£¬¾§Ìå¹ÜT1¡¢T2ÌØÐÔÏàͬ£¬ÇÒ?1£½?2£½29£¬rbb¡¯1£½rbb¡¯2£½300?£¬VBE1£½VBE2£½0.7V£¬ñîºÏµçÈÝC1¡¢C2¡¢C3µÄµçÈÝÁ¿¾ù×ã¹»´ó¡£ÊÔ¼ÆË㣺

£¨1£©¾²Ì¬¹¤×÷µçÁ÷ºÍµçѹ£ºIBQ1¡¢ICQ1¡¢VCEQ1¡¢IBQ2¡¢ICQ2¡¢VCEQ2£» £¨2£©µçѹ·Å´ó±¶ÊýAv?vovi£¬ÊäÈëµç×èRiºÍÊä³öµç×èRo¡£

+VCC Rb1C1TviRiRo1Rc1C2 Rb2Rc2TC32vo

ͼÌâ4.36

½â£º

£¨1£© IBQ1?IBQ2?VCC?VBE?22.6?A RbICQ1?ICQ2??IBQ?0.66mA VCEQ1?VCEQ2?VCC?ICRc?10.02V

£¨2£© rbe1?rbe2?rbb???1???26?1.5k?

IEQAv1?vo1?Rc1//Rb2//rbe2???19.3 virbe1Av2?

vo2?Rc2???58 vi2rbe2

Av?vo?Av1Av2?1120 viRi=Rb1//rbe1 ? rbe1=1.5k? Ro=Rc2=3k?

4.37Á½¼¶×èÈÝñîºÏ·Å´óµç·ÈçͼÌâ4.37Ëùʾ¡£ÉèT1µÄIDSS£½1mA£¬gm£½1mS£¬T2µÄ?£½30£¬rbb¡¯£½300?£¬VBE£½0.7V£¬ÉèµçÈÝÆ÷¶Ô½»Á÷Ðźžù¿ÉÊÓΪ¶Ì·¡£ÊÔ¹ÀË㣺

£¨1£©T1¡¢T2µÄ¾²Ì¬¹¤×÷µã£ºIDQ¡¢VDSQ¡¢IBQ¡¢ICQ¡¢VCEQ£» £¨2£©µçѹ·Å´ó±¶ÊýAv?vovi¡¢ÊäÈëµç×èRiºÍÊä³öµç×èRo¡£

Rd6.2k?Rb147k?C2 C1T1Rc5.1k?TRe1100?Re21.8k?2+VCC (+12V)C3viRg3.3M?RiRb213k?RL6.8k?CeRovo

ͼÌâ4.37

½â£º

£¨1£©VGS1=0V£¬ËùÒÔ£¬ IDQ?IDSS?1mA

VDSQ?VCC?IDQRd?5.8V

VB2?VCCRb2?2.6V

Rb1?Rb2VB?VBE?1mA

Re1?Re2ICQ1???33¦ÌA

ICQ?IEQ?IBQ?VCEQ?VCC?ICQ(Rc?Re1?Re2)?5V

£¨2£© rbe1?rbb??(1??)26?1.1k? IEQAv1 ??gm?Rd//Rb1//Rb2//?rbe??1???Re1????2

Av2????Rc//RL???20.8 rbe??1???Re1Av?Av1?Av2?42

Ri?Rg?3.3M?

Ro?Rc?5.1k?