L6223A ST Microelectronics, Inc., L6223A Datasheet - Page 9

• Manufacturer Part Number: L6223A
• Description: Dmos Programmable High Speed Unipolar Stepper Motor Driver
• Manufacturer: ST Microelectronics, Inc.

ing diagram for programming. When the inputs
IN1...IN4 are together Low a clock pulse is gener-
ated internally which clocks a data bit into the
shift register. If the time interval during which all
four inputs are Low is less than 0.2 s, no clocks
pulse in generated thus preventing undesirable
programming. To generate another clock pulse at
least one of the four inputs must first go High and
then Low again. The first bit is loaded into C0 and
after 6 clock pulse it will be in the C5 posistion.
Two programming technique are suggested. The
first (Fig. 8) uses IN4 in such a way that the
Figure 8: Waveform for programming: the output is disabled during all the programming duration (see Table 4).
Figure 9: Waveform for programming: the output is disabled only when all four inputs are at the low level.
power section is disabled the total programming
time (the carriage of the 6 programming bits). Fig.
9 shows another technique: the motor driving sig-
nals at the inputs IN1...IN4 are interrupted switch-
ing IN1...IN4 Low to carry a single bit. This per-
mits the motor to be enabled for the 50% of total
programming time. During the motor rotation it’s
suggested to program the device immediately af-
ter the motor phase change: this make neglect-
able the motor driving discontinuity due to the de-
vice programming.
L6223A
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