自学产 比较图215和图216 B3=43(A3B3)+B3(42B3)=A3由B3=(4=B3) P2=A2④B2=(42=B2) B=A1④B1=(A4=B1) 0=A④B0=(A0=B0) (A=B)o=(A4=B3)(A2=B2)(A1=BA=B)(A=B) 2021/223 作者:清华大学电子工程系罗嵘 第75页
2021/2/23 作者：清华大学电子工程系罗嵘 第75页 ( ) ( ) ( ) P3 ＝A3 A3 B3 + B3 A3 B3 = A3 B3 = A3 = B3 ( ) ( ) ( ) 0 0 0 0 0 1 1 1 1 1 2 2 2 2 2 P A B A B P A B A B P A B A B = = = = = = = = = 比较图2.15和图2.16 自学 A B O A B A B A B A B A B I ( ) ( )( )( )( )( ) = = 3 = 3 2 = 2 1 = 1 0 = 0 =
自学 A>B)=(4=B3)(A2=B2)(A4=B1(4=B)A=B) (2=B3)X42=B2C4=B)4=BMA<b +(A4<B3)+(A3=B3)(A2<B2) +(A3=B3)(A2=B2)(A4<B1) (A>B)=AB 0.1.2.3 +(4=BX42=B2M4=B14<B)(4<B)=AB i=0.12.3 (4<B)o=(4=B3)(2=B2XA=B1(A=B(4=B) +(A3=B42=B2)(4=B)A=B(A>B) +(A3>B3)+(A3=B3)(A2>B2) +(A3=B3)(A2=B2)A4>B1) +(43=B3)(A2=B2)(A1=B1)(A>B0) 2021/223 作者:清华大学电子工程系罗嵘 第76页
2021/2/23 作者：清华大学电子工程系罗嵘 第76页 ( )( )( )( ) ( )( )( ) ( ) ( )( ) ( )( )( )( )( ) ( ) ( )( )( )( )( ) 3 3 2 2 1 1 0 0 3 3 2 2 1 1 3 3 3 3 2 2 3 3 2 2 1 1 0 0 3 3 2 2 1 1 0 0 A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B I O I + = = = + = = + + = + = = = = = = = = = = ( )( )( )( ) ( )( )( ) ( ) ( )( ) ( )( )( )( )( ) ( ) ( )( )( )( )( ) 3 3 2 2 1 1 0 0 3 3 2 2 1 1 3 3 3 3 2 2 3 3 2 2 1 1 0 0 3 3 2 2 1 1 0 0 A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B A B I O I + = = = + = = + + = + = = = = = = = = = = ( ) 0,1,2,3 ( ) 0,1,2,3 = = = = A B A B i A B A B i i i i i i i i i 自学
自学 表2117485型四位数字比较器功能表 比较输入 级联输入 输出 A, B ,A, B,A, B,Ao, Bo(A<B)(A=B)(A>B)(A<B)o(A-Bo(A>)oI A>B A1<B3 A3=B,A2B2 A3=B3A2<B2 A=B3A2=B2A→B1 0 A2=B3A2=B2,A1<B A=B,A2=B2A=B, A>Bo 0 As-B3A2=B2AB, Ao <B 0000000000 A=B,A-B,A=B, AoBo 010 A=B,A=B,A=B,ABoI 400 0 0 A:=B,A=B,A=B A=Bo 0 010101010000 A=B3A2=B2A=B1A=B中 0 A=B,A=B,A=B A-B 0 0 A3=B3A2=B2A=B1A=B0000 0 2021/2/23作者:清华大学电子工程系罗嵘 第77页
2021/2/23 作者：清华大学电子工程系罗嵘 第77页 表 2.11 7485 型四位数字比较器功能表 比较输入 级联输入 输出 A3 ,B3 A2 ,B2 A1 ,B1 A0 ,B0 (A<B)I (A=B)I (A>B)I (A<B)O (A=B)O (A>B)O A3>B3 0 0 1 A3<B3 1 0 0 A3=B3 A2>B2 0 0 1 A3=B3 A2<B2 1 0 0 A3=B3 A2=B2 A1>B1 0 0 1 A3=B3 A2=B2 A1<B1 1 0 0 A3=B3 A2=B2 A1=B1 A0>B0 0 0 1 A3=B3 A2=B2 A1=B1 A0<B0 1 0 0 A3=B3 A2=B2 A1=B1 A0=B0 0 0 1 0 0 1 A3=B3 A2=B2 A1=B1 A0=B0 1 0 0 1 0 0 A3=B3 A2=B2 A1=B1 A0=B0 0 1 0 0 1 0 A3=B3 A2=B2 A1=B1 A0=B0 1 0 1 0 A3=B3 A2=B2 A1=B1 A0=B0 1 0 1 0 0 0 A3=B3 A2=B2 A1=B1 A0=B0 0 0 0 1 0 1 自学
自学 Ao Al A2 A3 A4 A5 A6 A7 A20A21A2A23 010BBB,B B,BBB B2122B323输入 PBo B B2 B3 > B2 B B B, BB I yU6 ADAAzA, Ao AA, a 山^A0A1A2A3 (A>B)(A-B)o(A<B)o (A>B)(A=B)0(A<B) (A>B)(A=B)(A<B) 输出 图2.1724位串行比较器 2021/223 作者:清华大学电子工程系罗嵘 第78页
2021/2/23 作者：清华大学电子工程系罗嵘 第78页 B0 B1 B2 B3 A0 A1 A2 A3 (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o 0 1 0 A0 A1 A2 A3 B0 B1 B2 B3 (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 B4 B5 B6 B7 A4A5 A6 A7 A0 A1 A2 A3 (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 B20B21B22B23 A0 A1 A2 A3 A20A21A22A23 …… 图2.17 24位串行比较器 I II VI 输出 输入 自学
输入一自学 Ao Aj A2 A3 As A6 A7 Agv A10A1A2A13 A20A21A2A2 010B0B1B2B119A10B, B, BB, Bs AgOB. BIoB,BLB A140B14B1sB16B1nB18A190B19B20B21B2B Bo B1 B B>SS Bo B, B2 B3 使的AAAM要 AoA:A:As A,A:ArAs要AAAA验9AAAA (A>BA=BA<B)(AB(A=BAB(A>B人(A=B(ABA(A>BA(A=BAB(AB(AB(A≤B Bo Bi BB v 3U6 AoA1A As (A>B)o(A=B)(A<B)o 输出 图2.1824位并行比较器 2021/223 作者:清华大学电子工程系罗嵘 第79页
2021/2/23 作者：清华大学电子工程系罗嵘 第79页 图2.18 24位并行比较器 010 A0 A1 A2 A3 B0 B1 B2B3 A40B4 (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 输出 输入 VI I (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 II (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 III (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 IV (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 V (A<B)I (A>B)I (A=B)I (A<B) (A=B)o o (A>B)o B0 B1 B2 B3 A0 A1 A2 A3 B5 B6 B7B8 A5 A6 A7 A8 A90B9 B10B11B12B13 A10A11A12A13 A140 B14B15B16B17B18 A15A16A17A18 A190 B19B20B21B22B23 A20A21A22A23 自学