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Электронный компонент: L6219DS

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DUAL FULL-BRIDGE
PWM MOTOR DRIVER
The L6219DS motor driver is designed to drive both windings of a
bipolar stepper motor or bidirectionally control two dc motors. Both
bridges are capable of sustaining 45 V and include internal pulse-width
modulation (PWM) control of the output current to 750 mA. The
outputs have been optimized for a low output saturation voltage drop
(less than 1.8 V total source plus sink at 500 mA).
For PWM current control, the maximum output current is deter-
mined by the user's selection of a reference voltage and sensing
resistor. Two logic-level inputs select output current limits of 0, 33,
67, or 100% of the maximum level. A PHASE input to each bridge
determines load current direction.
The bridges include both ground clamp and flyback diodes for
protection against inductive transients. Internally generated delays
prevent cross-over currents when switching current direction. Special
power-up sequencing is not required. Thermal protection circuitry
disables the outputs if the chip temperature exceeds safe operating
limits.
The L6219DS is supplied in a 24-lead surface-mountable SOIC. Its
batwing construction provides for maximum package power dissipation
in the smallest possible construction. This device is also available on
special order for operation from -40
C to +85C or to +105C.
FEATURES
I Interchangeable with SGS L6219DS
I 750 mA Continuous Output Current
I 45 V Output Sustaining Voltage
I Internal Clamp Diodes
I Internal PWM Current Control
I Low Output Saturation Voltage
I Internal Thermal Shutdown Circuitry
I Similar to Dual PBL3717, UC3770
Data Sheet
29319.43
L6219DS
1
2
3
4
5
6
7
8
9
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
2
1
V
CC
PWM 2
PWM 1
2
V
BB
1
GROUND
GROUND
GROUND
GROUND
02
I
12
I
PHASE
2
V
REF 2
2
RC
1
RC
V
REF 1
PHASE
1
11
I
2B
OUT
SENSE
2
2
COMP IN
2A
OUT
1A
OUT
1
COMP IN
SENSE
1
1B
OUT
01
I
LOAD
SUPPLY
LOGIC
SUPPLY
Dwg. PP-005-3
Always order by complete part number, e.g., L6219DS .
ABSOLUTE MAXIMUM RATINGS
at T
J
150
C
Motor Supply Voltage, V
BB
.................... 45 V
Output Current, I
OUT
(Peak) ........................................ +1.0 A
(Continuous) .......................... +750 mA
Logic Supply Voltage, V
CC
................... 7.0 V
Logic Input Voltage Range,
V
IN
............................... -0.3 V to +7.0 V
Output Emitter Voltage, V
SENSE
............ 1.5 V
Package Power Dissipation,
P
D
........................................................
See Graph
Operating Temperature Range,
T
A
................................. -20
C to +85
C
Storage Temperature Range,
T
S
............................... -55
C to +150
C
Output current rating may be limited by duty
cycle, ambient temperature, and heat sinking.
Under any set of conditions, do not exceed the
specified peak current rating or a junction
temperature of +150
C.
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
L6219DS
DUAL FULL-BRIDGE
MOTOR DRIVER
Copyright 1998 Allegro MicroSystems, Inc.
PWM CURRENT-CONTROL CIRCUITRY
TRUTH TABLE
PHASE
OUT
A
OUT
B
H
H
L
L
L
H
V
REF
Dwg. EP-007-5
V
BB
COMP IN
ONE
SHOT
SOURCE
DISABLE
RC

+
I
0
I
1
10
SENSE
OUT A
OUTB
CHANNEL 1
TERMINAL NUMBERS
SHOWN.
RC
R
S
R
T
C
C
C
T
24
20 k
40 k
10 k
21
1
23
22
14
20
17
15
50
75
100
125
150
2.5
1.5
1.0
0.5
0
TEMPERATURE in
C
2.0
25
Dwg. GP-019B
R = 6
C/W
JT
R = 55
C/W
JA
ALLOWABLE PACKAGE POWER DISSIPATION in WATTS
L6219DS
DUAL FULL-BRIDGE
MOTOR DRIVER
Limits
Characteristic
Symbol
Test Conditions
Min.
Typ.
Max.
Units
Output Drivers (OUT
A
or OUT
B
)
Motor Supply Range
V
BB
10
--
45
V
Output Leakage Current
I
CEX
V
OUT
= V
BB
--
< 1.0
50
A
V
OUT
= 0
--
<-1.0
-50
A
Output Sustaining Voltage
V
CE(sus)
I
OUT
=
750 mA, L = 3.0 mH
45
--
--
V
Output Saturation Voltage
V
CE(SAT)
Sink Driver, I
OUT
= +500 mA
--
0.4
0.6
V
Sink Driver, I
OUT
= +750 mA
--
1.0
1.2
V
Source Driver, I
OUT
= -500 mA
--
1.0
1.2
V
Source Driver, I
OUT
= -750 mA
--
1.3
1.5
V
Clamp Diode Leakage Current
I
R
V
R
=
45 V
--
< 1.0
50
A
Clamp Diode Forward Voltage
V
F
I
F
= 750 mA
--
1.6
2.0
V
Driver Supply Current
I
BB(ON)
Both Bridges On, No Load
--
20
25
mA
I
BB(OFF)
Both Bridges Off
--
5.0
10
mA
Control Logic
Input Voltage
V
IN(1)
All inputs
2.4
--
--
V
V
IN(0)
All inputs
--
--
0.8
V
Input Current
I
IN(1)
V
IN
= 2.4 V
--
<1.0
20
A
V
IN
= 0.8 V
--
- 3.0
-200
A
Reference Voltage Range
V
REF
Operating
1.5
--
7.5
V
Current Limit Threshold
V
REF
/ V
COMPIN
I
0
= I
1
= 0.8 V
9.5
10
10.5
--
I
0
= 2.4 V, I
1
= 0.8 V
13.5
15
16.5
--
I
0
= 0.8 V, I
1
= 2.4 V
25.5
30
34.5
--
Thermal Shutdown Temperature
T
J
--
170
--
C
Total Logic Supply Current
I
CC(ON)
I
0
= I
1
= 0.8 V, No Load
--
40
50
mA
I
CC(OFF)
I
0
= I
1
= 2.4 V, No Load
--
10
12
mA
(at trip point)
ELECTRICAL CHARACTERISTICS at T
A
= +25
C, T
J
150
C, V
BB
= 45 V, V
CC
= 4.75 V to 5.25 V,
V
REF
= 5.0 V (unless otherwise noted).
115 Northeast Cutoff, Box 15036
Worcester, Massachusetts 01615-0036 (508) 853-5000
L6219DS
DUAL FULL-BRIDGE
MOTOR DRIVER
APPLICATIONS INFORMATION
PWM CURRENT CONTROL
The L6219DS dual bridge is designed
to drive both windings of a bipolar stepper
motor. Output current is sensed and con-
trolled independently in each bridge by an
external sense resistor (R
S
), internal com-
parator, and monostable multivibrator.
When the bridge is turned on, current
increases in the motor winding and it is
sensed by the external sense resistor until
the sense voltage (V
COMPIN
) reaches the level
set at the comparator's input:
I
TRIP
= V
REF
/10 R
S
The comparator then triggers the
monostable which turns off the source driver
of the bridge. The actual load current peak
will be slightly higher than the trip point
(especially for low-inductance loads) be-
cause of the internal logic and switching
delays. This delay (t
d
) is typically 2
s. After
turn-off, the motor current decays, circulating
through the ground-clamp diode and sink
transistor. The source driver's off time (and
therefore the magnitude of the current
decrease) is determined by the monostable's
external RC timing components, where
t
off
= R
T
C
T
within the range of 20 k
to
100 k
and 100 pF to 1000 pF.
When the source driver is re-enabled,
the winding current (the sense voltage) is
again allowed to rise to the comparator's
threshold. This cycle repeats itself, maintain-
ing the average motor winding current at the
desired level.
Loads with high distributed capaci-
tances may result in high turn-on current
peaks. This peak (appearing across R
S
)
will attempt to trip the comparator, resulting
in erroneous current control or high-fre-
quency oscillations. An external R
C
C
C
time
delay should be used to further delay the
action of the comparator. Depending on load
type, many applications will not require these
external components (SENSE connected to
COMP IN).
PWM OUTPUT CURRENT WAVE FORM
LOAD CURRENT PATHS
+
0
Dwg. WM-003-1A
V
PHASE
I
OUT
t
d
t
off
I
TRIP
Dwg. EP-006-1
R S
BB
V
BRIDGE ON
SOURCE OFF
ALL OFF
L6219DS
DUAL FULL-BRIDGE
MOTOR DRIVER
LOGIC CONTROL OF OUTPUT CURRENT
Two logic level inputs (l
0
and I
1
) allow digital selection of the motor
winding current at 100%, 67%, 33%, or 0% of the maximum level per
the table. The 0% output current condition turns off all drivers in the
bridge and can be used as an OUTPUT ENABLE function.
CURRENT-CONTROL TRUTH TABLE
l
0
I
1
Output Current
L
L
V
REF
/10 R
S
= I
TRIP
H
L
V
REF
/15 R
S
= 2/3 I
TRIP
L
H
V
REF
/30 R
S
= 1/3 I
TRIP
H
H
0
These logic level inputs greatly enhance the implementation of
P-controlled drive formats.
During half-step operations, the l
0
and l
1
allow the
P to control the
motor at a constant torque between all positions in an eight-step
TYPICAL APPLICATION
sequence. This is accomplished by digitally
selecting 100% drive current when only one
phase is on and 67% drive current when two
phases are on. Logic highs on both l
0
and l
1
turn off all drivers to allow rapid current decay
when switching phases. This helps to ensure
proper motor operation at high step rates.
The logic control inputs can also be
used to select a reduced current level (and
reduced power dissipation) for `hold' condi-
tions and/or increased current (and available
torque) for start-up conditions.
GENERAL
The PHASE input to each bridge
determines the direction motor winding
current flows. An internally generated
deadtime (approximately 2
s) prevents
crossover currents that can occur when
switching the PHASE input.
All four drivers in the bridge output can
be turned off between steps (l
0
= l
1
2.4 V)
resulting in a fast current decay through the
internal output clamp and flyback diodes. The
fast current decay is desirable in half-step and
high-speed applications. The PHASE, l
0
,and I
1
inputs float high.
Varying the reference voltage (V
REF
)
provides continuous control of the peak load
current for microstepping applications.
Thermal protection circuitry turns off all
drivers when the junction temperature
reaches +170
C. It is only intended to protect
the device from failures due to excessive
junction temperature and should not imply
that output short circuits are permitted. The
output drivers are re-enabled when the
junction temperature cools to +145
C.
The L6219DS output drivers are opti-
mized for low output saturation voltages--less
than 1.8 V total (source plus sink) at 500 mA.
Under normal operating conditions, when
combined with the excellent thermal proper-
ties of the batwing package design, this
allows continuous operation of both bridges
simultaneously at 500 mA.
FROM
P
V
REF
Dwg. EP-008-2
V
BB
FROM
P
V
REF
+5 V
STEPPER
MOTOR
R
S
R
S
R
C
R
C
R
T
R
T
C
T
C
T
C
C
C
C
+
1
2
3
4
5
6
7
8
9
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
2
1
V
CC
PWM 2
PWM 1
2
V
BB
1