for:char printed on:mon, feb 6, 1995 09:49:57 from book:dl121ch4 (5) view document:mc74f382 (5) view last saved on:fri, feb 3, 1995 16:07:09
4-184 fast and ls ttl data 4-bit arithmetic logic unit the mc54/74f382 performs three arithmetic and three logic operations on two 4-bit words, a and b. t wo additional select input codes force the function outputs low or high. an overflow output is provided for convenience in twos complement arithmetic. a carry output is provided for ripple expansion. for high-speed expansion using a carry lookahead generator , refer to the f381 data sheet. ? performs six arithmetic and logic functions ? selectable low (clear) and high (preset) functions ? low input loading minimizes drive requirements ? carry output for ripple expansion ? overflow output for twos complement arithmetic connection diagram 18 17 16 15 14 13 1 2 3 4 5 6 7 20 19 8 v cc a 1 a 2 b 2 a 3 b 3 c n+4 c n ovr b 1 a 0 b 0 s 0 s 1 s 2 f 0 9 10 f 1 gnd 12 11 f 3 f 2 logic symbol c n s 2 s 1 s 0 c n+4 ovr a 0 b 3 a 3 b 2 a 2 b 0 a 1 b 1 f 0 f 3 f 2 f 1 3 4 1 2 19 18 17 16 15 7 6 5 14 13 8 9 11 12 guaranteed operating ranges symbol parameter min typ max unit v cc supply voltage 54, 74 4.5 5.0 5.5 v t a operating ambient temperature range 54 55 25 125 c t a operating ambient temperature range 74 0 25 70 c i oh output current e high 54, 74 1.0 ma i ol output current e low 54, 74 20 ma mc54/74f382 4-bit arithmetic logic unit fast ? schottky ttl ordering information mc54fxxxj ceramic mc74fxxxn plastic mc74fxxxdw soic 20 1 j suffix ceramic case 732-03 20 1 n suffix plastic case 738-03 20 1 dw suffix soic case 751d-03
4-185 fast and ls ttl data mc54/74f382 logic diagram please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays. c n b 0 a 0 b 1 a 1 b 2 a 2 b 3 a 3 s 0 s 1 s 2 f 0 f 1 f 2 f 3 p g ovr c n +4 f381 only f382 only
4-186 fast and ls ttl data mc54/74f382 dc characteristics over operating temperature range (unless otherwise specified) symbol parameter limits unit test conditions symbol parameter min typ max unit test conditions v ih input high voltage 2.0 v guaranteed input high voltage v il input low voltage 0.8 v guaranteed input low voltage v ik input clamp diode voltage 1.2 v i in = 18 ma v cc = min v oh output high voltage 54, 74 2.5 3.4 v i oh = 1.0 ma v cc = 4.5 v v oh output high voltage 74 2.7 3.4 v i oh = 1.0 ma v cc = 4.75 v v ol output low voltage 0.35 0.5 v i ol = 20 ma v cc = min i ih input high current 20 m a v in = 2.7 v v cc = max i ih input high current 100 m a v in = 7.0 v v cc = max i il input low current s 0 s 2 inputs 0.6 ma v in = 0.5 v v cc = max i il other inputs 2.4 ma v in = 0.5 v v cc = max c n input 3.0 ma i os output short circuit current (note 2) 60 150 ma v out = 0 v v cc = max i cc power supply current 54 81 ma s 0 , c n = high; other inputs gnd v cc = max notes: 1. for conditions such as min or max, use the appropriate value specified under guaranteed operating ranges. 2. not more than one output should be shorted at a time, nor for more than 1 second. functional description signals applied to the select inputs s 0 s 2 determine the mode of operation, as indicated in the function select t able. an extensive listing of input and output levels is shown in the truth t able. the circuit performs the arithmetic functions for either active high or active low operands, with output levels in the same convention. in the subtract operating modes, it is necessary to force a carry (high for active high operands, low for active low operands) into the c n input of the least significant package. ripple expansion is illustrated in figure 1. the overflow output ovr is the exclusive-or of c n + 3 and c n+4 ; a high signal on ovr indicates overflow in twos complement operation. t ypical delays for figure 1 are given in figure 2. function select table select operation s 0 s 1 s 2 operation l l l clear h l l b minus a l h l a minus b h h l a plus b l l h a b h l h a + b l h h ab h h h preset h = high v oltage level l = low v oltage level
4-187 fast and ls ttl data mc54/74f382 figure 1. 16-bit ripple carry alu expansion select 3 3 c in a 0 a 3 b 0 b 3 a 4 a 7 b 4 b 7 a 8 a 11 b 8 b 11 a 12 a 15 b 12 b 15 4 4 a b c n s f382 c n +4 ovr f 12 f 15 f 0 f 3 f 4 f 7 f 8 f 11 overflow c out 3 4 4 a b c n s f382 c n +4 3 4 4 a b c n s f382 c n +4 3 4 4 a b c n s f382 c n +4 path segment toward f output c n + 4 , ovr path segment toward f output c n + 4 , ovr a i or b i to c n + 4 6.5 ns 6.5 ns c n to c n + 4 6.3 ns 6.3 ns c n to c n + 4 6.3 ns 6.3 ns c n to f 8.1 e c n to c n + 4 , ovr e 8.0 ns total delay 27.2 ns 27.1 ns figure 2. 16-bit delay tabulation ac characteristics symbol parameter 54/74f 54f 74f unit symbol parameter t a = +25 c t a = 55 to +125 c t a = 0 to 70 c unit symbol parameter v cc = +5.0 v v cc = 5.0 v 10% v cc = 5.0 v 10% unit symbol parameter c l = 50 pf c l = 50 pf c l = 50 pf unit symbol parameter min typ max min max min max unit t plh propagation delay 3.0 8.1 12 3.0 15 3.0 13 ns t phl c n to f i 2.5 5.7 8.0 2.5 11 2.5 9.0 ns t plh propagation delay 4.0 10.4 15 4.0 18 4.0 16 ns t phl any a or b to any f 3.5 8.2 11 3.5 14 3.5 12 ns t plh propagation delay 6.0 11 15 6.0 21 6.0 16 ns t phl s i to f i 4.0 8.2 20.5 4.0 23.5 4.0 21.5 ns t plh propagation delay 3.5 6.0 8.5 3.5 11.5 3.5 9.5 ns t phl a i or b i to c n + 4 3.0 6.5 9.0 3.0 12.5 3.0 10.5 ns t plh propagation delay 7.0 12.5 16.5 7.0 19.5 7.0 17.5 ns t phl s i to ovr or c n + 4 4.5 9.0 12 4.5 15 4.5 13 ns t plh propagation delay 2.5 5.6 8.0 2.5 11 2.5 9.0 ns t phl c n to c n + 4 2.5 6.3 9.0 2.5 12 2.5 10 ns t plh propagation delay 3.5 8.0 11 3.5 14 3.5 12 ns t phl c n to ovr 3.5 7.1 10 3.5 13 3.5 11 ns t plh propagation delay 6.5 11.5 15.5 6.5 18.5 6.5 16.5 ns t phl a i or b i to ovr 5.5 8.0 10.5 5.5 13.5 5.5 11.5 ns
4-188 fast and ls ttl data mc54/74f382 truth table inputs outputs function s 0 s 1 s 2 c n a n b n f 0 f 1 f 2 f 3 ovr c n + 4 clear 0 0 0 0 x x 0 0 0 0 1 1 clear 0 0 0 1 x x 0 0 0 0 1 1 b minus a 1 0 0 0 0 0 1 1 1 1 0 0 b minus a 1 0 0 0 0 1 0 1 1 1 0 1 b minus a 1 0 0 0 1 0 0 0 0 0 0 0 b minus a 1 0 0 0 1 1 1 1 1 1 0 0 b minus a 1 0 0 1 0 0 0 0 0 0 0 1 1 0 1 1 1 1 1 0 1 1 1 0 1 0 0 0 0 0 1 1 1 0 0 0 0 0 1 0 1 0 0 0 0 1 1 1 1 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0 1 0 0 1 0 0 1 1 1 0 1 a minus b 0 1 0 0 1 1 1 1 1 1 0 0 a minus b 0 1 0 1 0 0 0 0 0 0 0 1 1 0 1 1 0 0 0 0 0 1 1 0 1 1 1 1 0 1 1 1 1 0 0 0 0 0 1 a plus b 0 0 0 0 0 0 0 0 0 a plus b 0 0 1 1 1 1 1 0 0 a plus b 0 1 0 1 1 1 1 0 0 a plus b 1 1 0 0 1 1 0 1 1 1 0 1 1 1 0 1 0 0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 1 1 1 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 1 x 0 0 0 0 0 0 0 0 x 0 1 1 1 1 1 0 0 a b 0 0 1 0 1 0 1 1 1 1 0 0 x 1 1 0 0 0 0 1 1 1 1 0 1 1 1 1 1 1 x 0 0 0 0 0 0 0 0 x 0 1 1 1 1 1 0 0 a + b 1 0 1 x 1 0 1 1 1 1 0 0 0 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 x 0 0 0 0 0 0 1 1 x 0 1 0 0 0 0 0 0 ab 0 1 1 x 1 0 0 0 0 0 1 1 0 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 x 0 0 1 1 1 1 0 0 x 0 1 1 1 1 1 0 0 preset 1 1 1 x 1 0 1 1 1 1 0 0 0 1 1 1 1 1 1 0 0 1 1 1 1 1 1 1 1 1 1 = high voltage level 0 = low voltage level x = immaterial
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