MOTOROLA MC1488D1013TR Rs-232c quad line driver Datasheet

MC1488
RS-232C QUAD LINE DRIVER
■
■
■
■
■
CURRENT LIMITED OUTPUT ±10mA TYP.
POWER-OFF SOURCE IMPEDANCE 300Ω
MIN.
SIMPLE SLEW RATE CONTROL WITH
EXTERNAL CAPACITOR
FLEXIBLE OPERATING SUPPLY RANGE
INPUTS ARE TTL AND µP COMPATIBLE
DESCRIPTION
The MC1488 is a monolithic quad line driver
designed to interface data terminal equipment
with data communications equipment in
conformance with the specifications of EIA
Standard No. RS232C.
DIP
SOP
LOGIC DIAGRAM
August 2003
1/12
MC1488
PIN CONFIGURATION
ORDERING CODES
DIP14
SO14
SO14 (TAPE & REEL)
MC1488P
MC1488D1
MC1488D1013TR
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
VS
Power Supply Voltage
VEE
Power Supply Voltage
VIR
Input Voltage Range
VO
Output Signal Voltage
Tamb
Operating Ambient Temperature
Tstg
Storage Temperature Range
Value
Unit
15
V
-15
V
VIR = -15 to 7
V
±15
V
0 to 75
°C
-65 to 150
°C
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.
THERMAL DATA
Symbol
Rthj-amb
2/12
Parameter
Thermal Resistance Junction-ambient Max
Plastic DIP14
Ceramic DIP14
SO14
Unit
200
165
165
°C/W
MC1488
ELECTRICAL CHARACTERISTICS
VS = 9V ± 10%, VEE = -9V ± 10%, Tamb = 0 to 75°C, unless otherwise specified.
Symbol
Parameter
Test Conditions
Min.
IIL
Input Current (Fig 1)
Low Logic State VIL = 0 V
IIH
Input Current (Fig 1)
High Logic State VIH = 5 V
Output Voltage (Fig. 2)
VS = 9V, VEE = -9V
High Logic State
RL = 3K, VIL = 0.8 V V = 13V, V = -13V
S
EE
VS = -9V, VEE = 9V
Low Logic State
VIH = 1.9 V
V = -13.2V, V =13.2V
VOH
VOL
Output Voltage (Fig. 2)
EE
IOS+*
IOS-*
RO
IS
IEE
PC
Positive Output ShortCircuit Current (Fig. 3)
Negative Output ShortCircuit Current (Fig. 3)
Output Resistance (Fig. 4) VS = VEE = 0
Positive Supply Current
(RI = ∞) (Fig. 5)
Negative Supply Current
(RL = ∞) (Fig. 5)
Power Consumption
S
VOL = ± 2V
Typ.
Max.
Unit
1
1.6
mA
10
µA
6
7
9
10.5
V
-6
-7
-9
-10.5
V
6
10
12
mA
-6
-10
-12
mA
Ω
300
VIH = 1.9 V
VS = 9 V
15
20
VIL = 0.8 V
VS = 9 V
4.5
6
VIH = 1.9 V
VS = 12 V
19
25
VIL = 0.8 V
VS = 12 V
5.5
7
VIH = 1.9 V
VS = 15 V
34
VIL = 0.8 V
VS = 15 V
12
mA
VIH = 1.9 V
VS = -9 V
VIL = 0.8 V
VS = -9 V
VIH = 1.9 V
VS = -12 V
VIL = 0.8 V
VS = -12 V
-15
µA
VIH = 1.9 V
VS = -15 V
-34
mA
VIL = 0.8 V
VS = -15 V
-2.5
VS = 9 V
VEE = -9 V
333
VS = 12 V
VEE = -12 V
567
-13
-18
-17
mA
-15
µA
-23
mA
mW
SWITCHING CHARACTERISTICS
VS = 9 ± 1V, VEE = -9 ± 1V, Tamb = 25°C
Symbol
Parameter
tPHL
Propagation Delay Time (Fig 6)
tTHL
Fall Time (Fig 6)
tPHL
Propagation Delay Time (Fig 6)
tTHL
Fall Time (Fig 6)
Test Conditions
Min.
Typ.
Max.
Unit
ZI = 3 KΩ and 15 pF
275
350
ns
ZI = 3 KΩ and 15 pF
45
75
ns
ZI = 3 KΩ and 15 pF
110
175
ns
ZI = 3 KΩ and 15 pF
55
100
ns
* Maximum package power dissipation may be exceeded if all outputs are shorted simultaneously.
3/12
MC1488
TEST CIRCUITS
Figure 1 : Input Current
Figure 2 : Output Voltage
Figure 3 : Output Short-Circuit Current
4/12
MC1488
Figure 4 : Output Resistance (power off)
Figure 5 : Power Supply Currents
Figure 6 : Switching Response
5/12
MC1488
Figure 7 : Transfer Characteristics vs Input
Voltage
Figure 10 : Output Voltage and Current Limiting
Characteristics
Figure 8 : Short-Circuit Output Current vs
Temperature
Figure 11 : Maximum Operating Temperature vs
Power Supply Voltage
Figure 9 : Output Slew-Rate Load Capacitance
6/12
MC1488
TYPICAL APPLICATIONS: RS232C Data Transmission
APPLICATION INFORMATION
The Electronic Industries Association (EIA) has released the RS232C specification detailing the
requirements for the interface between data processing equipment. This standard specifies not only the
number and type of interface leads, but also the voltage levels to be used. The MC1488 quad driver and
its companion circuit, the MC1489 quad receiver, provide a complete interface system between DTL or
TTL logic levels and the RS232C defined levels. The RS232C requirements as applied to drivers are
discussed herein.
The required driver voltages are defined as between 5 and 15V in magnitude and are positive for a logic
"0" and negative for a logic "1". These voltages are so defined when the drivers are terminated with a 3000
to 7000Ω resistor. The MC1488 meets this voltage requirement by converting a DTL/TTL logic level into
RS232C levels with one stage of inversion.
The RS232C specification further requires that during transitions, the driver output slew rate must not
exceed 30V per µs. The inherent slew rate of the MC1488 is much too fast for this requirement. The
current limited output of the device can be used to control this slew rate by connecting a capacitor to each
driver output. The required capacitor can be easily determined by using the relationship C = IOS x ∆T/∆V
from which Figure 12 is derived. Accordingly, a 330 pF capacitor on each output will guarantee a worst
case slew rate of 30V per µs.
The interface driver is also required to withstand an accidental short to any other conductor in an
interconnecting cable. The worst possible signal on any conductor would be another driver using a plus or
minus 15V, 500 mA source. The MC1488 is designed to indefinitely withstand such a short to all four
outputs in a package as long as the power-supply voltages are greater than 9.0V (i.e., VS ≥ 9.0V; VEE ≤
9.0V). In some power-supply designs, a loss of system power causes a low impedance on the
power-supply outputs. When this occurs, a low impedance to ground would exist at the power inputs to the
MC1488 effectively shorting the 300W output resistor to ground. If all four outputs were then shorted to
plus or minus 15 V, the power dissipation in these resistors would be excessive. Therefore, if the system
is designed to permit low impedances to ground at the power-supplies of the drivers, a diode should be
placed in each power-supply lead to prevent over-heating in this fault condition. These two diodes, as
shown in Figure 13, could be used to decoupled all the driver packages in a system. (These same diodes
will allow the MC1488 to withstand momentary shorts to the ±15V limits specified in the earlier Standard
7/12
MC1488
RS232B). The addition of the diodes also permits the MC1488 to withstand faults with power-supplies of
less than the 9.0V stated above.
The maximum short-circuit current allowable under fault conditions is more than guaranteed by the
previously mentioned 10 mA output current limiting.
The MC1488 is an extremely versatile line driver with a mired of possible applications. Several features of
the drivers enhance this versatility:
1. Output Current Limiting - this enables the circuit designer to define the output voltage levels
independent of power-supplies and can be accomplished by diode clamping of the output pins.
2. Power-Supply Range - as can be seen from the schematic drawing of the drivers, the positive and
negative driving elements of the device are essentially independent and do not require matching
power-supplies. In fact, the positive supply can very from a minimum seven volts (required for driving the
negative pulldown section) to the maximum specified 15 V. The negative supply can vary from
approximately -2.5 V to the minimum specified - 15 V. The MC1488 will drive the output to within 2 V of the
positive or negative supplies as long as the current output limits are not exceeded. The combination of the
current-limiting and supply-voltage features allow a wide combination of possible outputs within the same
quad package.
Figure 12 : Slew-Rate Load VS Capacitance for
ISC = 10 mA
Figure 13 : Power Supply Protection to Meet Power-off Fault Conditions
8/12
MC1488
Plastic DIP-14 MECHANICAL DATA
mm.
inch
DIM.
MIN.
a1
0.51
B
1.39
TYP
MAX.
MIN.
TYP.
MAX.
0.020
1.65
0.055
0.065
b
0.5
0.020
b1
0.25
0.010
D
20
0.787
E
8.5
0.335
e
2.54
0.100
e3
15.24
0.600
F
7.1
0.280
I
5.1
0.201
L
Z
3.3
1.27
0.130
2.54
0.050
0.100
P001A
9/12
MC1488
SO-14 MECHANICAL DATA
DIM.
mm.
MIN.
TYP
A
a1
inch
MAX.
MIN.
TYP.
1.75
0.1
0.068
0.2
a2
MAX.
0.003
0.007
1.65
0.064
b
0.35
0.46
0.013
0.018
b1
0.19
0.25
0.007
0.010
C
0.5
0.019
c1
45˚ (typ.)
D
8.55
8.75
0.336
0.344
E
5.8
6.2
0.228
0.244
e
1.27
0.050
e3
7.62
0.300
F
3.8
4.0
0.149
0.157
G
4.6
5.3
0.181
0.208
L
0.5
1.27
0.019
0.050
M
S
0.68
0.026
8 ˚ (max.)
PO13G
10/12
MC1488
Tape & Reel SO-14 MECHANICAL DATA
mm.
inch
DIM.
MIN.
A
TYP
MAX.
MIN.
330
MAX.
12.992
C
12.8
D
20.2
0.795
N
60
2.362
T
13.2
TYP.
0.504
22.4
0.519
0.882
Ao
6.4
6.6
0.252
0.260
Bo
9
9.2
0.354
0.362
Ko
2.1
2.3
0.082
0.090
Po
3.9
4.1
0.153
0.161
P
7.9
8.1
0.311
0.319
11/12
MC1488
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from
its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications
mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information
previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or
systems without express written approval of STMicroelectronics.
© The ST logo is a registered trademark of STMicroelectronics
© 2003 STMicroelectronics - Printed in Italy - All Rights Reserved
STMicroelectronics GROUP OF COMPANIES
Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco
Singapore - Spain - Sweden - Switzerland - United Kingdom - United States.
© http://www.st.com
12/12
Similar pages