B1·(R3∥re2) β2R4≈-10 07 rbe A 2≈6634 R1=R1∥r1≈1.5kg R1=R4=2k 图(e) A=-g R2//he+(1+ B)R4I (1+B)R4 rhe +(+B)R R1=R1=10Mg2 R.=R,∥5+R243 3.6 B(R (1)Ad (2)△l B(R+Rw) B △o=△lc1-△lc2 B(R+ Ad rie 3 VBEQ*/ w +2IfoR=VEE, IEQ Rw+2Re BEQ 2≈0.517mA 26mv The =rbb+(1+B) ≈2.66kQ A= BR (1+B) R1=2re+(1+B)13 = =  =   =   =  −  − −  = 2k 1.5k 6634 107 62 ( ) i 4 i 1 be1 1 2 be2 2 4 2 be1 1 3 be2 1 R R R R r A A A r R A r R r A u u u u u ∥ ∥        图（e）     + + = = =  =   −  + + + = = − + +  −  − 43 1 10M 6 1 (1 ) (1 ) [ (1 ) ] 6 be 2 o 4 i 1 1 2 be 4 4 2 1 2 be 4 2     r R R R R R A A A r R R A A g R r R g R u u u u u m m ∥ ∥      3.6 be W c I O d O C1 C2 I be c I C2 be c W C1 be W c I O d ) 2 ( 2 2 ( ) (2) ) 2 ( (1) r R R u u A u u u u r R u u r R R u r R R u u A + = −   =  =  −     = −   +  = − + = −   =     3.7 = + +    − + + = − = + +    − +  + = = 2 (1 ) 10.4k 97 2 (1 ) 2.66k 26mV (1 ) 0.517mA 2 2 2 2 i be W W be c d E Q be bb' e W E E BEQ E Q e E E E Q W BEQ E Q R r R R r R A I r r R R V U I R V I R U I     ＋