OM9373SP International Rectifier Corp., OM9373SP Datasheet - Page 5

• Manufacturer Part Number: OM9373SP
• Description: Full-featured Power Module For Direct Drive Of 3-phase Brushless Dc Motor
• Manufacturer: International Rectifier Corp.

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The OM9373 3-phase brushless DC motor controller/
driver is designed to drive fractional to integral
horsepower motors. To ensure proper operation, it is
necessary to ensure that the high-side bootstrap
capcitors are charged during initial start-up. However,
the method(s) used to ensure this may be dependant
upon the application. For example, some applications
may only require that OV_COAST (pin 17) be
connected to ground, either via a hardwire connection
or via a switch (Enable/Disable), before applying Vcc.
When Vcc is applied, the controller/driver is forced
into brake mode for approximately 200µs (all high-
side drivers are disabled and all low-side drivers are
enabled).
APPLICATIONS
Start-Up Conditions
Fig 1: Optional Start-Up Circuit
This may not be adequate for other applications;
while maintaining a constant speed command,(above
zero),the RC_BRAKE (pin 16) may have to be
momentarily connected to ground via a switch,
either manually or electronically (ref. Figure 1).
Note that with the component values shown in
Figure 1, RC_BRAKE is pulled for low for approximately
300ms after applying Vcc at pin 1.
OM9373
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