L6731B

Pin connections and functions

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8

OCL

A resistor connected from this pin to ground sets the valley- current-limit. The valley

current is sensed through the low-side MOSFET(s). The internal current generator

Connecting a capacitor from this pin to GND helps in reducing the noise injected from

related to the GND. Connect a capacitor only to a "clean" GND.

9

OCH

A resistor connected from this pin and the high-side MOSFET(s) drain sets the peak-

current-limit. The peak current is sensed through the high-side MOSFET(s). The

equation:

10

PHASE

This pin is connected to the source of the high-side MOSFET(s) and provides the

return path for the high-side driver. This pin monitors the drop across both the upper

and lower MOSFET(s) for the current limit together with OCH and OCL.

11

HGATE

This pin is connected to the high-side MOSFET(s) gate.

12

BOOT

Through this pin is supplied the high-side driver. Connect a capacitor from this pin to

13

PGND

This pin has to be connected closely to the low-side MOSFET(s) source in order to

reduce the noise injection into the device.

14

LGATE

This pin is connected to the low-side MOSFET(s) gate.

15

5V internally regulated voltage. It is used to supply the internal drivers. Filter it to

ground with at least 1µF ceramic cap.

16

Supply voltage pin. The operative supply voltage range is from 4.5V to 14V.

Table 3.

Pin functions

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