2547
PROTECTED
QUAD POWER DRIVERS
2547
PROTECTED
QUAD POWER DRIVERS
Providing interface between low-level logic and power loads, the
UDK/UDN/UDQ2547B and UDK/UDN/UDQ2547EB quad power
drivers combine logic gates and high-current bipolar outputs with
complete output protection. Each of the four outputs will sink 600 mA
in the ON state. The outputs have a minimum breakdown voltage
(load dump) of 60 V and a sustaining voltage of 40 V. The inputs are
compatible with TTL and 5 V CMOS logic systems and include internal
pull-down resistors to ensure that the outputs remain OFF if the inputs
are open-circuited.
Over-current protection for each channel has been designed into
these devices and is activated at approximately 1.3 A. It protects each
output from short circuits with supply voltages up to 25 V. When a
maximum driver output current is reached, that output drive is reduced
linearly, maintaining a constant load current. If the over-current or
short circuit condition continues, each channel has an independent
thermal limit circuit which will sense the rise in junction temperature
and turn OFF the individual channel that is at fault. Foldback circuitry
decreases the output current if excessive voltage is present across the
output and assists in keeping the device within its SOA (safe operating
area).
Each output also includes diagnostics for increased device protec-
tion. If any output is shorted or opened, the diagnostics can signal the
controlling circuitry through a common FAULT pin.
These devices can be used to drive various resistive loads includ-
ing incandescent lamps (without warming or limiting resistors). With
the addition of external output clamp diodes, they can be used to drive
inductive loads such as relays, solenoids, or dc stepping motors.
The suffix ‘B’ devices are 16-pin power DIPs while the suffix ‘EB’
devices are 28-lead power PLCCs for surface-mount applications.
Both packages are of batwing construction to provide for maximum
package power dissipation.
Data Sheet
29317.4C
UDx2547B
FAULT
OUT
1
OUT
2
GROUND
GROUND
OUT
3
NO
CONNECT.
OUT
4
1
2
3
4
5
6
7
8
V
CC
16
15
14
13
12
11
10
9
IN
1
IN
2
ENABLE
GROUND
GROUND
SUPPLY
IN
3
IN
4
Dwg. PP-018A
ABSOLUTE MAXIMUM RATINGS
at T
A
= 25
°
C
Output Voltage, V
OUT
............................
60 V
Over-Current Protected Output Voltage,
V
OUT
...............................................
25 V
Output Current, I
OUT
..........................
1.3 A*
FAULT Output Voltage, V
F
...................
40 V
Supply Voltage, V
CC
............................
7.0 V
Input Voltage, V
IN
or V
EN
......................
7.0 V
Package Power Dissipation,
P
D
........................................
See Graph
Operating Temperature Range, T
A
Prefix ‘UDK’ ...............
-40
°
C to +125
°
C
Prefix ‘UDN’ .................
-20
°
C to +85
°
C
Prefix ‘UDQ’ .................
-40
°
C to +85
°
C
Storage Temperature Range,
T
S
...............................
-55
°
C to +150
°
C
*Outputs are current limited at approximately
1.3 A per driver and junction temperature limited
if current in excess of 1.3 A is attempted. See
Circuit Description and Application for further
information.
FEATURES
s
s
s
s
s
Output SOA Protection
s
Low Output-Saturation Voltage
Diagnostic FAULT Output
s
TTL and 5 V CMOS Compatible Inputs
Independent Over-Current Protection for Each Driver
Independent Thermal Protection for Each Driver
600 mA Output Current per Channel
Always order by complete part number: a prefix to indicate operat-
ing temperature range + the basic four-digit part number + a suffix to
indicate package style, e.g.,
UDK2547EB
.
2547
PROTECTED
QUAD POWER DRIVERS
UDx2547EB
10
ALLOWABLE PACKAGE POWER DISSIPATION IN WATTS
OUT
2
NO
CONNECTION
FAULT
IN
1
R
θJT
= 6°C/W
GROUND
5
NC
25
FAULT
6
7
24
23
22
21
20
19
NC
NC
V
CC
GROUND
GROUND
6
4
SUFFIX 'EB', R
θJA
8
= 36°C/W
9
10
GROUND
11
2
SUFFIX 'B', R
θJA
= 43°C/W
15
12
13
14
16
25
50
NO
CONNECTION
NO
CONNECTION
OUT
4
OUT
3
IN
4
IN
3
Dwg. GP-004-1A
SUPPLY
75
100
TEMPERATURE IN
°C
125
150
17
18
0
28
27
26
3
1
8
4
2
IN
2
ENABLE
OUT
1
Dwg. PP-019
FUNCTIONAL BLOCK DIAGRAM
FAULT
ABLE
COMMON CONTROL
ONE OF FOUR DRIVERS
IN N
THERMAL
SHUTDOWN
CURRENT
LIMIT
OUTN
<<1
Ω
Dwg. FP-007
115 Northeast Cutoff, Box 15036
W
Worcester, Massachusetts 01615-0036 (508) 853-5000
Copyright © 1989, 1993, Allegro MicroSystems, Inc.
2547
PROTECTED
QUAD POWER DRIVERS
ELECTRICAL CHARACTERISTICS at T
A
= +25
°
C (prefix ‘UDN’) or over operating
temperature range (prefix ‘UDK’ or ‘UDQ’), V
CC
= 4.75 V to 5.5 V
Characteristic
Output Leakage Current*
Symbol
I
OUT
Test Conditions
V
OUT
= 60 V, V
IN
= 0.8 V, V
EN
= 2.0 V
V
OUT
= 60 V, V
IN
= 2.0 V, V
EN
= 0.8 V
Output Sustaining Voltage
Output Saturation Voltage
V
OUT(SUS)
V
OUT(SAT)
I
OUT
= 100 mA, V
IN
= 0.8 V, V
CC
= Open
I
OUT
= 400 mA
I
OUT
= 500 mA
I
OUT
= 600 mA
Over-Current Limit
Input Voltage
I
OUT
Logic 1
Logic 0
Input Current
Logic 1
Logic 0
Fault Output Leakage Current
Fault Output Current
I
F
I
F
5 ms PulseTest, V
OUT
= 5.0 V
V
IN(1)
or V
EN(1)
V
lN(0)
or V
EN(0)
V
IN(1)
or V
EN(1)
= 2.0 V
V
IN(0)
or V
EN(0)
= 0.8 V
V
F
= 40 V
V
F
= 40 V, Driver Outputs Open,
V
IN
= 0.8 V, V
EN
= 2.0 V
Fault Output Saturation Voltage
Total Supply Current
V
F(SAT)
I
CC
I
F
= 30
µA
All Outputs ON
All Outputs OFF
Thermal Shutdown
Thermal Hysteresis
T
J
∆T
J
40
—
—
—
—
—
60
0.1
45
6.0
165
15
80
0.4
50
10
—
—
µA
V
mA
mA
°C
°C
Min.
—
—
40
—
—
—
—
2.0
—
—
10
—
Limits
Typ.
Max.
30
30
—
—
—
—
1. 3
—
—
—
—
<1.0
150
150
—
300
400
550
1.7
—
0.8
60
—
2.0
Units
µA
µA
V
mV
mV
mV
A
V
V
µA
µA
µA
Typical Data is for design information only.
*Measurement includes XOR input current
and other elements.
TRUTH TABLE
STATUS
Normal Load
IN
N
H
L
X
H
H
L
ENABLE
H
H
L
H
H
H
OUT
N
L
H
H
R
H
L
FAULT
H
H
H
L
L
L
Over-Current or
Short to Supply
Thermal Fault
Open Load or
Short to Ground
X = Don’t care.
R = Linear drive, current limited.
2547
PROTECTED
QUAD POWER DRIVERS
CIRCUIT DESCRIPTION AND APPLICATION
NORMAL LAMP IN-RUSH CURRENT
NOT TO SCALE
LAMP CURRENT
These devices monitor their outputs for open or shorted conditions.
Both conditions are sensed by comparing the input and output states.
Note that the FAULT output is operational only if the ENABLE input is
high. When a fault condition is sensed, the FAULT output will go to a
low state. An external FAULT output filter capacitor (0.1µF) is recom-
mended to eliminate erroneous switching.
INCANDESCENT LAMP DRIVER
SHORT CIRCUIT
CURRENT LIMIT
High incandescent lamp turn-ON/in-rush currents can contribute to
poor lamp reliability and destroy semiconductor lamp drivers.
Warming (parallel) or current-limiting (series) resistors protect both
driver and lamp but use significant power either when the lamp is OFF
or when the lamp is ON, respectively. Lamps with steady-state current
ratings up to 600 mA can be driven without the need for warming or
current-limiting resistors, if lamp turn-ON time is not a concern.
When an incandescent lamp is initially turned ON, the cold filament
is at minimum resistance and would normally allow a 10x to 12x in-rush
current. With these drivers, during turn-ON, the high in-rush current is
sensed by the internal low-value sense resistor, drive current to the
output stage is diverted by the shunting transistor, the output stage
operates in a linear mode, and the load current is limited to approxi-
mately 1.3 A. During lamp warmup, the filament resistance increases
to its maximum value, the output driver goes into saturation and applies
maximum rated voltage to the lamp.
INDUCTIVE LOAD DRIVER
With the addition of external clamp diodes, bifilar (unipolar)
stepper motors and other inductive loads can be driven directly.
The external diodes prevent damage to the output transistors by
suppressing the high-voltage spikes that occur when turning
OFF an inductive load. For rapid current decay (fast turn-OFF speeds),
the use of Zener diodes will raise the flyback voltage and improve
performance. However, the peak voltage must not exceed the speci-
fied minimum sustaining voltage (V
SUPPLY
+ V
Z
+ V
F
≤
V
OUT(SUS)
).
OVER-CURRENT CONDITIONS
In the event of a shorted load, or stalled motor, the load current
will attempt to increase. As described above, the drive current to the
affected output stage is linearly reduced (limiting the load current to
about 1.3 A), causing the output stage to go linear. As the junction
temperature of the output stage increases, the thermal shutdown circuit
will shut OFF the affected output. If the fault condition is corrected, the
output driver will return to its normal saturated condition.
THERMAL SHUTDOWN
THERMAL HYSTERESIS
TIME
Dwg. WP-005A
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
2547
PROTECTED
QUAD POWER DRIVERS
UDN2547B and UDQ2547B
Dimensions in Inches
(controlling dimensions)
16
NOTE 4
9
0.020
0.008
0.430
0.280
0.240
MAX
0.300
BSC
1
0.070
0.045
0.100
0.775
0.735
BSC
8
0.005
MIN
0.210
MAX
0.015
MIN
0.150
0.115
0.022
0.014
Dwg. MA-001-17A in
Dimensions in Millimeters
(for reference only)
16
NOTE 4
9
0.508
0.204
10.92
7.11
6.10
MAX
7.62
BSC
1
1.77
1.15
2.54
19.68
18.67
BSC
8
0.13
MIN
5.33
MAX
0.39
MIN
3.81
2.93
0.558
0.356
Dwg. MA-001-17A mm
NOTES: 1.
2.
3.
4.
Exact body and lead configuration at vendor’s option within limits shown.
Lead spacing tolerance is non-cumulative
Lead thickness is measured at seating plane or below.
Webbed lead frame. Leads 4, 5, 12, and 13 are internally one piece.
