Quad Bidirectional
Instrumentation Bus (GPIB)
Transceiver
This bidirectional bus transceiver is intended as the interface between
TTL or MOS logic and the IEEE Standard Instrumentation Bus (488–1978,
often referred to as GPIB). The required bus termination is internally
provided.
Each driver/receiver pair forms the complete interface between the bus
and an instrument. Either the driver or the receiver of each channel is
enabled by its corresponding Send/Receive input with the disabled output of
the pair forced to a high impedance state. An additional option allows the
driver outputs to be operated in an open collector* or active pull–up
configuration. The receivers have input hysteresis to improve noise margin,
and their input loading follows the bus standard specifications.
•
Four Independent Driver/Receiver Pairs
MC3448A
QUAD THREE–STATE
BUS TRANSCEIVER WITH
TERMINATION NETWORKS
SEMICONDUCTOR
TECHNICAL DATA
•
•
•
•
•
•
•
•
•
•
Three–State Outputs
High Impedance Inputs
Receiver Hysteresis – 600 mV (Typical)
Fast Propagation Times – 15 to 20 ns (Typical)
TTL Compatible Receiver Outputs
Single 5.0 V Supply
Open Collector Driver Output Option*
Power Up/Power Down Protection
(No Invalid Information Transmitted to Bus)
No Bus Loading When Power Is Removed From Device
Terminations Provided: Termination Removed When Device is
Unpowered
D SUFFIX
PLASTIC PACKAGE
CASE 751B
(SO–16)
P SUFFIX
PLASTIC PACKAGE
CASE 648
PIN CONNECTIONS
Send/Rec.
1
Input A
Data A
2 T
D
R
16 VCC
15 Send/Rec.
Input D
14 Data D
D
R
* Selection of the “Open Collector” configuration, in fact, selects an open collector device with
*
a passive pull–up load/termination which conforms to Figure 7, IEEE 488–1978 Bus Standard.
TRUTH TABLE
Send/Rec.
0
1
1
X = Don′t Care
Enable
X
1
0
Info. Flow
Bus
→
Data
Data
→
Bus
Data
→
Bus
Comments
–
Active Pull–Up
Open Col.
Bus A 3
Pull–Up
Enable 4
Input A–B
Bus B 5
Data B 6
R
T
D
R
T 13 Bus D
Pull–Up
12 Enable
Input C–D
T 11 Bus C
D
Send/Rec.
7
Input B
Gnd 8
10 Data C
9 Send/Rec.
Input C
– T– = Bus Termination
Typical Measurement System Application
Instrument
A
(With GPIB)
Instrument
B
(With GPIB)
Programmable
Calculator
(With GPIB)
VCC
1.7 k
3.9 k
ORDERING INFORMATION
Device
MC3448AP
MC3448AD
Operating
Temperature Range
TA = 0 to +70°C
Package
Plastic DIP
SO–16
16 Lines Total
7–58
MOTOROLA ANALOG IC DEVICE DATA
MC3448A
MAXIMUM RATINGS
(TA = 25°C, unless otherwise noted)
Rating
Power Supply Voltage
Input Voltage
Driver Output Current
Junction Temperature
Operating Ambient Temperature Range
Storage Temperature Range
Symbol
VCC
VI
IO(D)
TJ
TA
Tstg
Value
7.0
5.5
150
150
0 to +70
– 65 to +150
Unit
Vdc
Vdc
mA
°C
°C
°C
ELECTRICAL CHARACTERISTICS
(Unless otherwise noted, 4.75 V
TA = 25°C, VCC = 5.0 V)
Characteristic
Bus Voltage
(Bus Pin Open) (VI(S/R) = 0.8 V)
(I(BUS) = – 12 mA)
Bus Current
(5.0 V
V(BUS)
(V(BUS) = 0.5 V)
(VCC = 0 V, 0 V
p
VCC
p
5.25 V and 0
p
TA
p
70°C; typical values are at
Symbol
V(BUS)
VIC(BUS)
I(BUS)
0.7
– 1.3
–
–
VILH(R)
VIHL(R)
VOH(R)
VOL(R)
IOS(R)
VIH(D)
VIL(D)
II(D)
IIB(D)
II(S/R)
IIB(S/R)
II(E)
IIB(E)
VIC(D)
VOH(D)
VOL(D)
IOS(D)
400
–
0.8
2.7
–
– 15
2.0
–
– 200
–
– 100
–
– 200
–
–
2.5
–
– 30
–
–
–
600
1.6
1.0
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
2.5
– 3.2
+ 0.04
–
1.8
–
–
0.5
– 75
–
0.8
40
200
µA
20
100
µA
20
100
– 1.5
–
0.5
– 120
V
V
V
mA
mA
ICCL
ICCH
–
–
63
106
85
125
V
V
mA
V
V
µA
mV
V
Min
2.75
–
Typ
–
–
Max
3.7
– 1.5
mA
Unit
V
p
p
5.5 V)
p
V(BUS)
p
2.75 V)
Receiver Input Hysteresis (VI(S/R) = 0.8 V)
Receiver Input Threshold
(VI(S/R) = 0.8 V, Low to High)
(VI(S/R) = 0.8 V, High to Low)
Receiver Output Voltage – High Logic State
(VI(S/R) = 0.8 V, IOH(R) = – 800
µA,
V(BUS) = 2.0 V)
Receiver Output Voltage – Low Logic State
(VI(S/R) = 0.8 V, IOL(R) = 16 mA, V(BUS) = 0.8 V)
Receiver Output Short Circuit Current (VI(S/R) = 0.8 V, V(Bus) = 2.0 V)
Driver Input Voltage – High Logic State (VI(S/R) = 2.0 V)
Driver Input Voltage – Low Logic State (VI(S/R) = 2.0 V)
Driver Input Current – Data Pins (VI(S/R) = VI(E) = 2.0 V)
(0.5
VI(D)
2.7 V)
(VI(D) = 5.5 V)
p
p
Input Current – Send / Receive
(0.5
VI(S/R)
2.7 V)
(VI(S/R) = 5.5 V)
p
p
p
Input Current – Enable
(0.5
VI(E)
2.7 V)
(VI(E) = 5.5 V)
p
Driver Input Clamp Voltage (VI(S/R) = 2.0 V, IIC(D) = –18 mA)
Driver Output Voltage – High Logic State
(VI(S/R) = 2.0 V, VIH(D) = 2.0 V, VIH(E) = 2.0 V, IOH = – 5.2 mA)
Driver Output Voltage – Low Logic State (Note 1)
(VI(S/R) = 2.0 V, IOL(D) = 48 mA)
Output Short Circuit Current
(VI(S/R) = 2.0 V, VIH(D) = 2.0 V, VIH(E) = 2.0 V)
Power Supply Current
(Listening Mode – All Receivers On)
(Talking Mode – All Drivers On)
MOTOROLA ANALOG IC DEVICE DATA
7–59
MC3448A
SWITCHING CHARACTERISTICS
(VCC = 5.0 V, TA = 25°C, unless otherwise noted)
Propagation Delay of Driver
(Output Low to High)
(Output High to Low)
Propagation Delay of Receiver
(Output Low to High)
(Output High to Low)
ns
tPLH(D)
tPHL(D)
tPLH(R)
tPHL(R)
–
–
–
–
–
–
–
–
15
17
ns
25
23
NOTE:
1. A modification of the IEEE 488–1978 Bus Standard changes VOL(D) from 0.4 to 0.5 V maximum to permit the use of Schottky technology.
SWITCHING CHARACTERISTICS (continued)
(VCC = 5.0 V, TA = 25°C, unless otherwise noted)
Characteristic
Propagation Delay Time – Send/Receive to Data
Logic High to Third State
Third State to Logic High
Logic Low to Third State
Third State to Logic Low
Propagation Delay Time – Send/Receive to Bus
Logic High to Third State
Third State to Logic High
Logic Low to Third State
Third State to Logic Low
Turn–On Time – Enable to Bus
Pull–Up Enable to Open Collector
Open Collector to Pull–Up Enable
Symbol
tPHZ(R)
tPZH(R)
tPLZ(R)
tPZL(R)
tPHZ(D)
tPZH(D)
tPLZ(D)
tPZL(D)
tPOFF(E)
tPON(E)
Min
–
–
–
–
–
–
–
–
–
–
Typ
–
–
–
–
–
–
–
–
–
–
Max
30
30
30
30
ns
30
30
30
30
ns
30
20
Unit
ns
7–60
MOTOROLA ANALOG IC DEVICE DATA
MC3448A
PROPAGATION DELAY TEST CIRCUITS AND WAVEFORMS
Figure 1. Bus Input to Data Output (Receiver)
To Scope
(Output)
3.0 V
Input
1.5 V
1.5 V
0V
tPLH(R)
Output
1.5 V
tPHL(R)
VOH
1.5 V
VOL
51
f = 1.0 MHz
5.0 ns (10%
to 90%)
tTLH = tTHL
Duty Cycle = 50%
5.0 V
To Scope
(Input)
R
240
Data
Bus
D
CL*
30 pF
1N916
or Equiv.
p
Pulse
Generator
* Includes Jig and
*
Probe Capacitance
Send/Rec
Figure 2. Data Input to Bus Output (Driver)
To Scope
(Input)
R
Data
3.0 V
To Scope
(Output)
Send/
Rec
38.3
Pulse
Generator
Bus
51
D
CL*
Output
2.0 V
0.8 V
VOL
30 pF
f = 1.0 MHz
tTLH = tTHL
5.0 ns (10%
to 90%)
Duty Cycle = 50%
2.3 V
Driver Input
or Enable
tPLH(D)
1.5 V
1.5 V
0V
tPHL(D)
VOH
3.0 V
p
* Includes Jig and
*
Probe Capacitance
Pull–Up Enable
3.0 V
Figure 3. Send/Receive Input to Bus Output (Driver)
3.0 V
To Scope
(Output)
ZL
Bus
ZH
CL
13.5
Output
High to Open
90%
Input
1.5 V
tPZH(D)
2.0 V
0V
VZ
≈
1.1 V
0.8 V
VOL
tPZL(D)
0V
1.5 V
0V
VOH
ZH
ZL
Pull–Up
Enable
D
ZH
Data
Send/Rec
ZL
To Scope
(Input)
Pulse
Generator
51
CL = 15 pF (Includes Jig and
CL =
Probe Capacitance
R
480
tPHZ(D)
1.1 V
Output
Low to Open
10%
tPLZ(D)
f = 1.0 MHz
tTLH = tTHL
5.0 ns (10%
to 90%)
Duty Cycle = 50%
p
MOTOROLA ANALOG IC DEVICE DATA
7–61
MC3448A
Figure 4. Send/Receive Input to Data Output (Receiver)
3.0 V
Input
5.0 V
3.0 V
ZH
Bus
R
Send / Rec
ZL
To Scope
(Input)
51
Pulse
Generator
D
CL
ZH
3.0 k
Output
Low to Open
To Scope
(Output)
280
ZL
Data
Output
High to Open
tPHZ(R)
5.0 V
10%
tPLZ(R)
CL = 15 pF (Includes Jig and
CL =
Probe Capacitance
f = 1.0 MHz
tTLH = tTHL
5.0 ns (10%
to 90%)
Duty Cycle = 50%
1.5 V
VOL
tPZL(R)
0V
90%
1.5 V
tPZH(R)
VOH
1.5 V
0V
1.5 V
0V
p
Figure 5. Enable Input to Bus Output (Driver)
3.0 V
To Scope
(Output)
3.0 V
Data
D
Send/Rec
CL
To Scope
(Input)
Pulse
Generator
51
R
480
tPON(E)
Output
2.0 V
≈
1.0 V
CL = 15 pF (Includes Jig and
CL =
Probe Capacitance
f = 1.0 MHz
tTLH = tTHL
5.0 ns (10%
to 90%)
Duty Cycle = 50%
90%
Pull–Up
Enable Bus
Enable Input
1.5 V
1.5 V
0V
tPOFF(E)
VOH
VOC
p
Figure 6. Typical Receiver Hysteresis
Characteristics
5.0
VO, OUTPUT VOLTAGE (V)
VCC = 5.0 V
TA = 25°C
6.0
4.0
IBUS, BUS CURRENT (mA)
4.0
2.0
0
– 2.0
– 4.0
– 6.0
– 8.0
– 10
– 12
0
0
0.5
1.0
VI, INPUT VOLTAGE (V)
1.5
2.0
– 14
– 4.0
Figure 7. Typical Bus Load Line
3.0
2.0
1.0
Non–Shaded Area
Conforms to
Paragraph 3–5.3 of
IEEE Standard
488 –1978
VCC = 5.0 V
– 2.0
2.0
VBUS, BUS VOLTAGE (V)
0
4.0
6.0
7–62
MOTOROLA ANALOG IC DEVICE DATA
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