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INTEGRATED CIRCUITS
74F85
4-bit magnitude comparator
Product specification 1994 Sep 27
IC15 Data Handbook
Philips Semiconductors
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Philips Semiconductors Product specification
74F854-bit magnitude comparator
FEA TURES
•High-impedance NPN base inputs for reduced loading
(20µA in High and Low states)
•Magnitude comparison of any binary words
•Serial or parallel expansion without extra gating
DESCRIPTION
The 74F85 is a 4-bit magnitude comparator that can be expanded to
almost any length. It compares two 4-bit binary, BCD, or other
monotonic codes and presents the three possible magnitude results
at the outputs. The 4-bit inputs are weighted (A0–A3) and (B0–B3)
where A3 and B3 are the most significant bits. The operation of the
74F85 is described in the Function Table, showing all possible logic
conditions. The upper part of the table describes the normal
operation under all conditions that will occur in a single device or in
a series expansion scheme. In the upper part of the table the three
outputs are mutually exclusive. In the lower part of the table, the
outputs reflect the feed-forward conditions that exist in the parallel
expansion scheme. The expansion inputs I
are the least significant bit positions. When used for series
expansion, the A>B, A=B and A<B outputs of the lease significant
word are connected to the corresponding I
of the next higher stage. Stages can be added in this manner to any
length, but a propagation delay penalty of about 15ns is added with
each additional stage. For proper operation, the expansion inputs of
the least significant word should be tied as follows: I
I
= High, and I
A=B
A<B
= Low.
A>B
A>B
, and I
, I
A=B
A=B
and I
A>B
and I
A<B
= Low,
A<B
inputs
PIN CONFIGURATION
1
B3
2
I
A<B
3
I
A=B
4
I
A>B
A>B
5
A=B
6
A<B
TYPE TYPICAL
PROPAGATION
DELAY
74F85 7.0ns 40mA
16
V
CC
15
A3
14
B2
13
A2
A1
12
B1
11
107
A0
98GND B0
SF00075
TYPICAL
SUPPLY CURRENT
(TOTAL)
ORDERING INFORMATION
COMMERCIAL RANGE
DESCRIPTION
16-pin plastic DIP N74F85N SOT38-4
16-pin plastic SO N74F85D SOT162-1
VCC = 5V ±10%,
T
= 0°C to +70°C
amb
PKG DWG #
INPUT AND OUTPUT LOADING AND FAN OUT TABLE
PINS DESCRIPTION 74F (U.L.) HIGH/LOW LOAD VALUE HIGH/LOW
A0–A3 Comparing inputs 1.0/0.033 20µA/20µA
B0–B3 Comparing inputs 1.0/0.033 20µA/20µA
I
, I
A=B
, I
A>B
A<B
A<B, A=B, A>B Data outputs (active High) 50/33 1.0mA/20mA
NOTE: One (1.0) FAST unit load is defined as: 20µA in the High state and 0.6mA in the Low state.
LOGIC SYMBOL
10 12 13 15 9 11 14
A0 A1 A2 A3 B0 B1 B2 B3
2
3
4
V
CC
GND = Pin 8
= Pin 16
I
A<B
I
A=B
I
A>B
Expansion inputs (active High) 1.0/0.033 20µA/20µA
IEC/IEEE SYMBOL
COMP
0
P
3
0
3
<
=
>
P<Q
P=Q
Q
P>Q
A>B A=B A<B
567
1
SF00076
10
12
13
15
9
11
14
1
2
3
4
7
6
5
SF00077
September 27, 1994 853–0055 13903
2
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Philips Semiconductors Product specification
74F854-bit magnitude comparator
LOGIC DIAGRAM
15
A3
1
B3
5
A>B
13
A2
14
B2
2
I
A<B
I
A=B
I
A>B
A1
B1
3
4
12
11
6
A=B
7
A<B
10
A0
9
B0
V
= Pin 16
CC
GND = Pin 8
SF00078
FUNCTION TABLE
COMPARING INPUTS EXPANSION INPUTS OUTPUTS
A3,B3 A2,B2 A1,B1 A0,B0 I
A>B
A3>B3 X X X X X X H L L
A3<B3 XXXXXXLHL
A3=B3 A2>B2 X X X XXHLL
A3=B3 A2<B2 X X X XXLHL
A3=B3 A2=B2 A1>B1 X X X X H L L
A3=B3 A2=B2 A1<B1 X X XXLHL
A3=B3 A2=B2 A1=B1 A0>B0 X XXHLL
A3=B3 A2=B2 A1=B1 A0<B0 X XXLHL
A3=B3 A2=B2 A1=B1 A0=B0 H L L H L L
A3=B3 A2=B2 A1=B1 A0=B0 L HLLHL
A3=B3 A2=B2 A1=B1 A0=B0 L LHLLH
A3=B3 A2=B2 A1=B1 A0=B0 X X H L L H
A3=B3 A2=B2 A1=B1 A0=B0 H HLLLL
A3=B3 A2=B2 A1=B1 A0=B0 L L L H H L
H = High voltage level
L = Low voltage level
X = Don’t care
I
A<B
I
A=B
A>B A<B A=B
September 27, 1994
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Philips Semiconductors Product specification
74F854-bit magnitude comparator
APPLICATION
The parallel expansion scheme shown in Figure 1 demonstrates the
INPUTS
B23
(LSB) B3
A23
B22
A22
B21
A21
B20
A20
B19
L
A19
B18
A18
B17
A17
B16
A16
B15
A15
B14
L
A14
A3
B2
A2
B1
A1
B0
A0
I
A<B
I
A=B
I
A>B
B3
A3
B2
A2
B1
A1
B0
A0
I
A<B
I
A=B
I
A>B
A<B
A=B
A>B
A<B
A=B
A>B
NC
NC
most efficient general use of these comparators. The expansion
inputs can be used as a fifth input bit position except on the least
significant device, which must be connected as in the serial scheme.
The expansion inputs used by labeling I
a “B” input and setting I
= Low. The 74F85 can be used as a 5-bit
A=B
as an “A” input, I
A>B
A<B
as
comparator only when the outputs are used to drive the (A0–A3) and
(B0–B3) inputs of another 74F85 device. The parallel technique can
be expanded to any number of bits as shown in Table 1.
Table 1.
WORD LENGTH
NUMBER OF
PACKAGES
1–4 bits 1 12ns
5–24 bits 2–6 22ns
25–120 bits 8–31 34ns
TYPICAL SPEEDS
74F
B13
A13
B12
A12
B11
A11
B10
A10
(LSB)
B3
A3
B2
A2
A<B
B1
A=B
A1
A>B
B0
A0
B9
I
A<B
L
I
A=B
A9
I
A>B
B8
B3
A8
A3
B7
B2
A7
A2
B6
B1
A<B
A1
A6
B5
A5
B4
L
A4
B3
A3
B2
A2
B1
A1
B0
A0
L
H
L
B0
A0
I
A<B
I
A=B
I
A>B
B3
A3
B2
A2
B1
A1
B0
A0
I
A<B
I
A=B
I
A>B
A=B
A>B
A<B
A=B
A>B
NC
NC
Figure 1. Comparison of Two 24-Bit Words
B3
A3
B2
A2
B1
A1
B0
A0
A<B
A=B
A>B
A<B
A=B
A>B
OUTPUTS
SF00079
September 27, 1994
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Philips Semiconductors Product specification
SYMBOL
PARAMETER
UNIT
SYMBOL
PARAMETER
TEST CONDITIONS
1
UNIT
VOHHigh-level output voltage
V
VOLLow-level output voltage
V
74F854-bit magnitude comparator
ABSOLUTE MAXIMUM RATINGS
(Operation beyond the limits set forth in this table may impair the useful life of the device.
Unless otherwise noted these limits are over the operating free-air temperature range.)
SYMBOL
V
V
I
IN
V
I
OUT
T
T
CC
IN
OUT
amb
stg
Supply voltage –0.5 to +7.0 V
Input voltage –0.5 to +7.0 V
Input current –30 to +5 mA
Voltage applied to output in High output state –0.5 to V
Current applied to output in Low output state 40 mA
Operating free-air temperature range 0 to +70 °C
Storage temperature range –65 to +150 °C
RECOMMENDED OPERATING CONDITIONS
V
V
V
I
I
I
T
CC
IH
IL
IK
OH
OL
amb
Supply voltage 4.5 5.0 5.5 V
High-level input voltage 2.0 V
Low-level input voltage 0.8 V
Input clamp current –18 mA
High-level output current –1 mA
Low-level output current 20 mA
Operating free-air temperature range 0 +70 °C
PARAMETER RATING UNIT
CC
V
LIMITS
MIN NOM MAX
DC ELECTRICAL CHARACTERISTICS
(Over recommended operating free-air temperature range unless otherwise noted.)
LIMITS
MIN TYP
p
p
V
IK
I
I
I
IH
I
IL
I
OS
I
CC
Input clamp voltage VCC = MIN, II = I
Input current at maximum input voltage VCC = 0.0V, VI = 7.0V 100 µA
High-level input current VCC = MAX, VI = 2.7V 20 µA
Low-level input current VCC = MAX, VI = 0.5V –20 µA
Short-circuit output current
3
Supply current (total)
VCC = MIN, VIL = MAX ±10%V
VIH = MIN, IOH = MAX ±5%V
VCC = MIN, VIL = MAX ±10%V
VIH = MIN, I
= MAX ±5%V
OL
IK
VCC = MAX –60 –150 mA
I
CCH
I
CCL
VCC = MAX
VIN = GND 36 50
An = Bn = I
I
= I
A>B
A<B
A=B
= 4.5V
CC
CC
CC
CC
= GND,
2.5
2.7 3.4
NOTES:
1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable type.
2. All typical values are at V
3. Not more than one output should be shorted at a time. For testing I
= 5V, T
CC
techniques are preferable in order to minimize internal heating and more accurately reflect operational values. Otherwise, prolonged shorting
amb
= 25°C.
, the use of high-speed test apparatus and/or sample-and-hold
OS
of a High output may raise the chip temperature well above normal and thereby cause invalid readings in other parameter tests. In any
sequence of parameter tests, I
tests should be performed last.
OS
2
MAX
0.30 0.50
0.30 0.50
–0.73 –1.2 V
40 54
mA
September 27, 1994
5
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Philips Semiconductors Product specification
TEST
CONDITION
74F854-bit magnitude comparator
AC ELECTRICAL CHARACTERISTICS
LIMITS
VCC = +5.0V VCC = +5.0V ± 10%
SYMBOL PARAMETER
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
t
PLH
t
PHL
Propagation delay
A or B to A<B, A>B
Propagation delay
A or B to A=B
Propagation delay
I
A<B
and I
A=B
to A>B
Propagation delay
I
to A=B
A=B
Propagation delay
I
A>B
and I
A=B
to A<B
Waveform 1
3 logic levels
Waveform 1
4 logic levels
Waveform 1
1 logic level
Waveform 1
2 logic levels
Waveform 1
1 logic level
T
= +25°C T
amb
= 0°C to +70°C UNIT
amb
CL = 50pF, RL = 500Ω CL = 50pF, RL = 500Ω
MIN TYP MAX MIN MAX
6.0
7.0
6.5
7.0
3.0
3.0
2.5
3.5
3.0
3.0
8.5
9.5
9.0
9.5
5.0
6.0
4.5
7.5
5.0
6.0
11.0
14.0
11.5
14.0
7.5
9.0
7.0
10.0
8.0
9.0
5.5
6.5
6.0
6.5
2.5
2.5
2.0
2.5
3.0
2.0
13.0
15.5
14.0
14.5
9.0
10.0
9.0
12.0
9.5
9.5
ns
ns
ns
ns
ns
AC WAVEFORMS
V
IN
V
OUT
V
M
t
PHL
Waveform 1. Propagation Delay Input to Output
NOTE:
For all waveforms, V
= 1.5V.
M
V
M
t
PLH
V
M
TEST CIRCUIT AND WAVEFORMS
V
CC
V
PULSE
GENERATOR
IN
R
T
Test Circuit for Totem-Pole Outputs
D.U.T.
V
OUT
C
L
V
SF00080
R
L
M
NEGATIVE
PULSE
POSITIVE
PULSE
90%
10%
t
w
V
M
10%
)
t
THL (tf
t
)
TLH (tr
90%
V
M
t
t
t
w
TLH (tr
THL (tf
10%
)
)
90%
V
M
V
M
90%
10%
AMP (V)
0V
AMP (V)
0V
DEFINITIONS:
R
= Load resistor;
L
see AC ELECTRICAL CHARACTERISTICS for value.
= Load capacitance includes jig and probe capacitance;
C
L
see AC ELECTRICAL CHARACTERISTICS for value.
R
= Termination resistance should be equal to Z
T
pulse generators.
September 27, 1994
OUT
of
family
74F
6
Input Pulse Definition
INPUT PULSE REQUIREMENTS
V
amplitude
3.0V
M
1.5V
rep. rate
1MHz 500ns
t
w
t
TLHtTHL
2.5ns 2.5ns
SF00006
Page 7
Philips Semiconductors Product specification
74F854-bit magnitude comparator
DIP16: plastic dual in-line package; 16 leads (300 mil) SOT38-4
1994 Sep 27
7
Page 8
Philips Semiconductors Product specification
74F854-bit magnitude comparator
SO16: plastic small outline package; 16 leads; body width 7.5 mm SOT162-1
1994 Sep 27
8
Page 9
Philips Semiconductors Product specification
74F854-bit magnitude comparator
NOTES
1994 Sep 27
9
Page 10
Philips Semiconductors Product specification
74F854-bit magnitude comparator
Data sheet status
Data sheet
status
Objective
specification
Preliminary
specification
Product
specification
Product
status
Development
Qualification
Production
Definition
This data sheet contains the design target or goal specifications for product development.
Specification may change in any manner without notice.
This data sheet contains preliminary data, and supplementary data will be published at a later date.
Philips Semiconductors reserves the right to make chages at any time without notice in order to
improve design and supply the best possible product.
This data sheet contains final specifications. Philips Semiconductors reserves the right to make
changes at any time without notice in order to improve design and supply the best possible product.
[1]
[1] Please consult the most recently issued datasheet before initiating or completing a design.
Definitions
Short-form specification — The data in a short-form specification is extracted from a full data sheet with the same type number and title. For
detailed information see the relevant data sheet or data handbook.
Limiting values definition — Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one
or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or
at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended
periods may affect device reliability.
Application information — Applications that are described herein for any of these products are for illustrative purposes only. Philips
Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or
modification.
Disclaimers
Life support — These products are not designed for use in life support appliances, devices or systems where malfunction of these products can
reasonably be expected to result in personal injury . Philips Semiconductors customers using or selling these products for use in such applications
do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application.
Right to make changes — Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard
cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no
responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these
products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless
otherwise specified.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 94088–3409
Telephone 800-234-7381
Copyright Philips Electronics North America Corporation 1998
All rights reserved. Printed in U.S.A.
print code Date of release: 10-98
Document order number: 9397-750-05067
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