DataSheet.es    


PDF 2927 Data sheet ( Hoja de datos )

Número de pieza 2927
Descripción DUAL FULL-BRIDGE PWM MOTOR DRIVER
Fabricantes Allegro MicroSystems 
Logotipo Allegro MicroSystems Logotipo



Hay una vista previa y un enlace de descarga de 2927 (archivo pdf) en la parte inferior de esta página.


Total 8 Páginas

No Preview Available ! 2927 Hoja de datos, Descripción, Manual

2927
DUAL FULL-BRIDGE
PWM MOTOR DRIVER
2927
PRELIMINARY INFORMATION
(Subject to change without notice)
September 16, 1997
DUAL FULL-BRIDGE
PWM MOTOR DRIVER
The A2927SEB 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 50 V and include internal pulse-width
modulation (PWM) control of the output current to 1.5 A.
GND 7 39 GND For PWM current control, the maximum output current is determined
8
9
10
T11
12
C13
U14
15
D Y16
PROE ONLGND 17
1
2
PWM 1
PWM 2
38
37
36
35
34
33
32
31
30
29 GND
Dwg. PP-021
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. Active-low ENABLE inputs control the four drivers in
each bridge.
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 A2927SEB is supplied in a 44-lead power PLCC for surface-
mount applications. Its batwing construction provides for maximum
package power dissipation in the smallest possible construction.
UED ENCABSOLUTE MAXIMUM RATINGS
Nat TJ +150°C
I RMotor Supply Voltage, VBB ................... 50 V
T EOutput Current, IOUT ......................... ±1.5 A
FLogic Supply Voltage, VCC ................... 7.0 V
NLogic Input Voltage Range,
EVIN ............................... -0.3 V to +7.0 V
O ROutput Emitter Voltage, VE .................. 1.0 V
CPackage Power Dissipation,
S RPD ........................................ See Graph
Operating Temperature Range,
I OTA ................................. -20°C to +85°C
D FStorage Temperature Range,
FEATURES
s 1.5 A Output Current
s 50 V Output Sustaining Voltage
s Internal Flyback Diodes
s Digital Control of Output Current
s Undervoltage Lockout
s Internal Thermal Shutdown Circuitry
TS ............................... -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.
Always order by complete part number: A2927SEB .

1 page




2927 pdf
2927
DUAL FULL-BRIDGE
PWM MOTOR DRIVER
CURRENT-CONTROL
TRUTH TABLE
I0 I1 Output Current
L L VREF/10 RS = ITRIP
H L VREF/15 RS = 2/3 ITRIP
L H VREF /30 RS = 1/3 ITRIP
HH
0
Loads with high distributed capacitances may result in
high turn-ON current peaks. This peak (appearing across
RS) will attempt to trip the comparator, resulting in errone-
ous current control or high-frequency oscillations. An
external RCCC low-pass filter may be needed to delay the
action of the comparator.
LOGIC CONTROL OF OUTPUT CURRENT:
Two logic level inputs (I0 and I1) 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. These logic level
inputs greatly enhance the implementation of µP-con-
trolled drive formats.
During half-step operations, the I0 and I1 inputs allow
the µP to control the motor at a constant torque between
all positions in an eight-step sequence. This is accom-
plished by digitally selecting 100% drive current when only
one phase is ON and 67% drive current when two phases
are ON.
The logic control inputs can also be used to select a
reduced current level (and reduced power dissipation) for
‘hold’ conditions and/or increased current (and available
torque) for start-up conditions.
GENERAL :
Both bridges have internal flyback diodes (connected
from the outputs to VBB) for protection against inductive
transients. External ground-clamp diodes (connected
from the outputs to ground) are required; Schottky
ground-clamp diodes are recommended to minimize on-
chip power dissipation.
To avoid excessive voltage spikes on the LOAD
SUPPLY terminal (VBB), a large-value capacitor (47 µF)
should be connected from VBB to ground as close as
possible to the device. Under no circumstances should
the voltage at LOAD SUPPLY exceed 50 V. A low-value
(0.1 µF) ceramic capacitor at this terminal may be used
for high-frequency noise suppression.
The PHASE input to each bridge determines the
direction motor winding current flows. An internally
generated deadtime (approximately 3 µs) prevents
crossover currents that can occur when switching the
PHASE input.
All four drivers in the bridge output can be turned OFF
(VEN 2.4 V or I0 = I1 2.4 V), resulting in a fast current
decay through the internal flyback and external ground-
clamp diodes. The fast current decay is desirable in half-
step and high-speed applications. All logic inputs float
high; the ENABLE input must be tied low if it is not used.
Varying the reference voltage (VREF) provides continu-
ous control of the peak load current for micro-stepping
applications, within the specified limits for VREF.
Thermal protection circuitry turns OFF all drivers
when the junction temperature reaches approximately
+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 reenabled when the junction tempera-
ture cools to approximately +160°C.

5 Page










PáginasTotal 8 Páginas
PDF Descargar[ Datasheet 2927.PDF ]




Hoja de datos destacado

Número de piezaDescripciónFabricantes
2920Microminiature Reed RelaysRHOPOINT COMPONENTS
RHOPOINT COMPONENTS
2920LResettable PTCs Surface MountLittelfuse
Littelfuse
2927DUAL FULL-BRIDGE PWM MOTOR DRIVERAllegro MicroSystems
Allegro MicroSystems
2929SQSquare Air Core InductorsCoilcraft
Coilcraft

Número de piezaDescripciónFabricantes
SLA6805M

High Voltage 3 phase Motor Driver IC.

Sanken
Sanken
SDC1742

12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters.

Analog Devices
Analog Devices


DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares,
permitiéndote verlos en linea o descargarlos en PDF.


DataSheet.es    |   2020   |  Privacy Policy  |  Contacto  |  Buscar