AN1451 Datasheet, PDF (1/43 Pages) STMicroelectronics – L6208 FULLY INTEGRATED TWO PHASE

AN1451
APPLICATION NOTE
L6208 FULLY INTEGRATED TWO PHASE
STEPPER MOTOR DRIVER
by Domenico Arrigo, Vincenzo Marano and Thomas Hopkins
Modern motion control applications need more flexibility that can be addressed only with specialized IC
products. The L6208 is a fully integrated stepper motor driver IC specifically developed to drive a wide range
of two phase (bipolar) stepper motors. This IC is a one-chip cost effective solution that includes several
unique circuit design features. These features, including a decoding logic that can generate three different
stepping sequences, allow the device to be used in many applications including microstepping. The principal
aim of this development project was to produce an easy to use, fully protected power IC. In addition several
key functions such as protection circuit and PWM current control drastically reduce external components
count to meet requirements for many different applications.
1 INTRODUCTION
The L6208 is a highly integrated, mixed-signal power IC that allows the user to easily design a complete motor
control system for two-phase bipolar stepper motors. Figure 1 shows the L6208 block diagram. The IC inte-
grates eight Power DMOS, a centralized logic circuit which implements the phase generation and a constant
t_OFF PWM current control technique (Quasi-Synchronous mode) for each of the two phases of the motor plus
other added features for safe operation and flexibility.
Figure 1. L6208 block diagram.
V_BOOT
V_CP
EN
CONTROL
HALF/FULL
CLOCK
RESET
CW/CCW
GND
GND
GND
GND
October 2003
V_BOOT
CHARGE
PUMP
THERMAL
PROTECTION
OCD_A
OCD_B
STEPPING
SEQUENCE
GENERATION
VOLTAGE
REGULATOR
10V 5V
L6208
V_BOOT
V_BOOT
V_SA
OVER
CURRENT
DETECTION
10V
GATE
LOGIC
ONE SHOT
MONOSTABLE
OVER
CURRENT
DETECTION
GATE
LOGIC
OUT1_A
OUT2_A
10V
PWM
MASKING
TIME
+
SENSE
-
COMPARATOR
BRIDGE A
BRIDGE B
D01IN1226
SENSE_A
VREF_A
RC_A
V_SB
OUT1_B
OUT2_B
SENSE_B
VREF_B
RC_B
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