74F521 Datasheet, PDF (2/8 Pages) NXP Semiconductors – 8-bit identity comparator

Philips Semiconductors
8-bit identity comparator
Product specification
74F521
FEATURES
• Compares two 8-bit words in 6.5ns typical
• Expandable to any word length
DESCRIPTION
The 74F521 is an expandable 8-bit comparator. It compares two
words of up to 8 bits each and provides a Low output when the two
words match bit for bit. The expansion input I_A=B also serves as an
active-Low enable input.
TYPE
74F521
TYPICAL
PROPAGATION
DELAY
7.0ns
TYPICAL
SUPPLY CURRENT
(TOTAL)
24mA
PIN CONFIGURATION
I_A=B ¹
A0 ²
B0 ³
A1 ⁴
B1 ⁵
A2 ⁶
B2 ⁷
A3 ⁸
B3 ⁹
GND ¹⁰
20 V_CC
19 _QA=B
18 _B7
17 _A7
16 _B6
15 _A6
14 _B5
13 _A5
12 _B4
11 _A4
SF00273
ORDERING INFORMATION
DESCRIPTION
20-pin plastic DIP
20-pin plastic SOL
COMMERCIAL RANGE
V_CC = 5V ±10%, T_amb = 0°C to +70°C
N74F521N
N74F521D
PKG DWG #
SOT146-1
SOT163-1
INPUT AND OUTPUT LOADING AND FAN-OUT TABLE
PINS
DESCRIPTION
74F (U.L.) HIGH/LOW
A0 – A7
Word A inputs
1.0/1.0
B0 – B7
Word B inputs
1.0/1.0
I_A=B
Expansion or Enable input (active Low)
1.0/1.0
Q_A=B
Identity output (active Low)
50/33
NOTE: One (1.0) FAST unit load is defined as: 20µA in the High state and 0.6mA in the Low state.
LOAD VALUE HIGH/LOW
20µA/0.6mA
20µA/0.6mA
20µA/0.6mA
1.0mA/20mA
LOGIC SYMBOL
2
3
4
5
6
7
8
9
11
12
13
14
15
16
17
18
V_CC = Pin 20
GND = Pin 10
1
I_A=B
A0
B0
A1
B1
A2
B2
A3
B3
Q_A=B
19
A4
B4
A5
B5
A6
B6
A7
B7
SF00274
IEC/IEEE SYMBOL
2
COMP
0
4
6
8
11
A
13
15
17
3
3
0
5
19
A=B
7
9
12
B
14
15
18
7
1
EN
SF00275
May 15, 1990
2
853–0372 99601