74HCT1284 Datasheet, PDF (2/12 Pages) NXP Semiconductors – Parallel printer interface transceiver/buffer

Philips Semiconductors
Parallel printer interface transceiver/buffer
Product specification
74HCT1284
FEATURES
• Asynchronous operation
• 4-Bit transceivers
• 3 additional buffer/driver lines
• TTL compatible inputs
• ESD protection exceeds 2000V per MIL STD 883 Method 3015
and 200V per Machine Model
• Input Hysteresis
• Low Noise Operation
• Center Pin V_CC & GND
• IEEE 1284 Compliant Level 1 & 2
• Overvoltage Protection on B side
DESCRIPTION
The 74HCT1284 parallel interface chip is designed to provide an
asynchronous, 4-bit, bi-directional, parallel printer interface for
personal computers. Three additional lines are included to provide
handshaking signals between the host and the peripheral. The part
is designed to match IEEE 1284 standard.
The 4 transceiver pins (A/B 1-4) allow data transmission from the A
bus to the B bus, or from the B bus to the A bus, depending on the
state of the direction pin DIR.
The B bus and the Y5-Y7 lines have totem pole or open drain style
outputs depending on the state of the high drive enable pin HD.
The A bus only has totem pole style outputs. All inputs are TTL
compatible with at least 400mV of input hysteresis at V_CC = 5.0V.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
t_PLH
t_PHL
C_IN
C_OUT
I_CC
Propagation delay
Bn to An
Input capacitance A_n, DIR, HD
Output capacitance B_n, Y_n
Total supply current
ORDERING INFORMATION
PACKAGES
20-pin plastic DIP
20-pin plastic SOL
20-pin plastic SSOP Type II
20-pin plastic TSSOP Type I
CONDITIONS
T_amb = 25°C; GND = 0V
C_L = 50pF; V_CC = 5V
V_I = 0V or V_CC
V_O = 0V or V_CC; 3-State
V_CC = 5.5V
TEMPERATURE RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
ORDER CODE
74HCT1284N
7HCT1284D
74HCT1284DB
74HCT1284PW
TYPICAL
5.3
5.6
5
14
500
UNIT
ns
ns
pF
pF
nA
DRAWING NUMBER
SOT146-1
SOT163-1
SOT339-1
SOT360-1
PIN CONFIGURATION
A1 ¹
A2 ²
A3 ³
A4 ⁴
GND ⁵
GND ⁶
A5 ⁷
A6 ⁸
A7 ⁹
DIR ¹⁰
20 B1
19 _B2
18 _B3
17 _B4
16 _VCC
15 _VCC
14 _Y5
13 _Y6
12 _Y7
11 _HD
SK00001
PIN DESCRIPTION
PIN NUMBER
SYMBOL
1,2,3,4
20,19,18,17
A1 - A4
B1 - B4
7,8,9
14,13,12
A5 - A7
Y5 - Y7
10,11
DIR,HIGH
DRIVE
5,6
GND
15,16
V_CC
FUNCTION
Data inputs/outputs
Buffer/Driver lines
Direction, Drive
Ground (0V)
Positive supply voltage
1998 Jul 10
2
853–1768 19693