
4-36
FAST AND LS TTL DATA
4-BIT MAGNITUDE COMPARATOR
The MC54/74F85 is a 4-Bit Magnitude Comparator which compares two
4-Bit words (A0-A3, B0-B3), A3, B3 being the most significant nputs. Operation
is not restricted to binary codes; the device will work with any monotonic code.
Three Outputs are provided: “A greater than B” (0A > B), “A less than B” (0A
< B), “A equal to B” (0A = B). Three Expander Inputs, IA > B, IA < B, IA = B, allow
cascading without external gates. For proper compare operation, the Expan-
der Inputs to the least significant position must be connected as follows: IA <
B = IA > B = L, IA = B = H. For serial (ripple) expansion the 0A > B, 0A < B Outputs
are connected respectively to the IA > B and IA = B inputs of the next most sig-
nificant comparator, as shown in Figure 1. Refer to applications section of
data sheet for high speed method of comparing large words.
High Impedance NPN Base Inputs for Reduced Loading (20
μ
A in
HIGH and LOW States)
Magnitude Comparison of any Binary Words
Serial or Parallel Expansion Without Extra Gating
ESD > 4000 Volts
CONNECTION DIAGRAM
15
16
14
13
12
11
10
2
1
3
4
5
6
7
VCC
9
8
A3
B2
A2
A1
B1
A0
B0
B3
IA<B
IA=B
IA>B
A>B
A=B
A<B
GND
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
VCC
Supply Voltage
54, 74
4.5
5.0
5.5
V
TA
Operating Ambient Temperature Range
54
–55
25
125
°
C
74
0
25
70
IOH
Output Current
High
54, 74
–1.0
mA
IOL
Output Current
Low
54, 74
20
mA
MC54/74F85
4-BIT MAGNITUDE COMPARATOR
FAST
SCHOTTKY TTL
J SUFFIX
CERAMIC
CASE 620-09
N SUFFIX
PLASTIC
CASE 648-08
16
1
16
1
ORDERING INFORMATION
MC74FXXJ
MC74FXXN
MC74FXXD
Ceramic
Plastic
SOIC
16
1
D SUFFIX
SOIC
CASE 751B-03