74F647 Datasheet, PDF (2/12 Pages) NXP Semiconductors – Octal transceiver/register, non-inverting open-collector

Philips Semiconductors
Octal transceivers/registers (open-collector)
Product specification
74F647/74F649
74F647 Octal Transceiver/Register, Non-inverting (Open Collector)
74F649 Octal Transceiver/Register, Inverting (Open Collector)
FEATURES
• High impedance NPN base inputs for reduced loading
(20µA in High and Low states)
• Independent registers for A and B buses
• Multiplexed real-time and stored data
• Choice of non-inverting and inverting data paths
• Open Collector outputs
• 300 mil wide 24-pin Slim Dip package
DESCRIPTION
The 74F647 and 74F649 Transceivers/Registers consist of bus
transceiver circuits with open-collector outputs, D-type flip-flops, and
control circuitry arranged for multiplexed transmission of data
directly from the input bus or from the internal registers. Data on the
A or B bus will be clocked into the registers as the appropriate clock
pin goes to a High logic level. Output Enable (OE) and DIR pins are
provided to control the transceiver function. In the transceiver mode,
data present at the high impedance port may be stored in either the
A or B register or both.
The select (SAB, SBA) controls can multiplex stored and real-time
(transparent mode) data. The DIR determines which bus will receive
data when the Output Enable, OE is active Low. In the isolation
mode (Output Enable, OE = High), data from Bus A may be stored
in the B register and/or data from Bus B may be stored in the A
register.
When an output function is disabled, the input function is still
enabled and may be used to store and transmit data. Only one of
the two buses, A or B, may be driven at a time. The following
examples demonstrate the four fundamental bus-management
functions that can be performed with the 74F647 and 74F649.
TYPE
74F647
74F649
TYPICAL
f_max
65MHz
65MHz
TYPICAL SUPPLY CURRENT
(TOTAL)
125mA
125mA
ORDERING INFORMATION
DESCRIPTION
COMMERCIAL RANGE
V_CC = 5V ±10%,
T_amb = 0°C to +70°C
24-pin plastic Slim
DIP (300mil)
N74F647N, N74F649N
24-pin plastic SOL N74F647D, N74F649D
PKG DWG #
SOT222-1
SOT137-1
PIN CONFIGURATION – 74F647
PIN CONFIGURATION – 74F649
CPAB 1
SAB 2
DIR 3
A0 ⁴
A1 ⁵
A2 ⁶
A3 ⁷
A4 ⁸
A5 ⁹
A6 ¹⁰
A7 ¹¹
GND 12
24 V_CC
23 CPBA
22 SBA
21 OE
20 _B0
19 _B1
18 _B2
17 _B3
16 _B4
15 _B5
14 _B6
13 _B7
SF01196
CPAB 1
SAB 2
DIR 3
A0 ⁴
A1 ⁵
A2 ⁶
A3 ⁷
A4 ⁸
A5 ⁹
A6 ¹⁰
A7 ¹¹
GND 12
24 V_CC
23 CPBA
22 SBA
21 OE
20 _B0
19 _B1
18 _B2
17 _B3
16 _B4
15 _B5
14 _B6
13 _B7
SF01196
1992 Feb 28
2
853-0876 05853