MC14585B 4-Bit Magnitude Comparator The MC14585B 4Bit Magnitude Comparator is constructed with complementary MOS (CMOS) enhancement mode devices. The circuit has eight comparing inputs (A3, B3, A2, B2, A1, B1, A0, B0), three cascading inputs (A < B, A = B, and A > B), and three outputs (A < B, A = B, and A > B). This device compares two 4bit words (A and B) MC14585B PIN ASSIGNMENT BLOCK DIAGRAM B2 1 16 V DD (A > B) 4 in A2 2 15 A3 6 (A = B) in (A < B) (A > B) 13 5 (A = B) 3 14 B3 in out out A0 10 (A B) 4 13 (A B) in out B0 11 (A B) 5 12 (A B) in out 7 A1 (A = B) 3 out B1 9 (A = B) 6 11 B0 in A2 2 A1 7 10 A0 B2 (A < B) 12 1 out V 8 9 B1 A3 SS 15 B3 14 V = PIN 16 DD V = PIN 8 SS TRUTH TABLE (x = Dont Care) Inputs Comparing Cascading Outputs A3, B3 A2, B2 A1, B1 A0, B0 A < B A = B A > B A < B A = B A > B A3 > B3 x x x x x x 0 0 1 A3 = B3 A2 > B2 x x x x x 0 0 1 A3 = B3 A2 = B2 A1 > B1 x x x x 0 0 1 A3 = B3 A2 = B2 A1 = B1 A0 > B0 x x x 0 0 1 A3 = B3 A2 = B2 A1 = B1 A0 = B0 0 0 x 0 0 1 A3 = B3 A2 = B2 A1 = B1 A0 = B0 0 1 x 0 1 0 A3 = B3 A2 = B2 A1 = B1 A0 = B0 1 0 x 1 0 0 A3 = B3 A2 = B2 A1 = B1 A0 = B0 1 1 x 1 1 0 A3 = B3 A2 = B2 A1 = B1 A0 < B0 x x x 1 0 0 A3 = B3 A2 = B2 A1 < B1 x x x x 1 0 0 A3 = B3 A2 < B2 x x x x x 1 0 0 A3 < B3 x x x x x x 1 0 0