FSUSB242

CONFIDENTIAL AND PROPRIETARY

NOT FOR PUBLIC RELEASE

www.onsemi.com

3

APPLICATION INFORMATION

Over Voltage Protection

Over voltage protection turns the switch off if the inputs

HSD+/HSD− rise above the over voltage trip threshold.

Under Voltage Lockout

With the SELpin active, the input voltage rising above the

UVLO threshold releases the lockout and enables the

switch.

Tri−State Input Control Pin (SEL)

The SEL pin can be tri−stated to disable the switch to save

power, there are a few ways to achieve this. If the SEL pin

is controlled by GPIO in the system, if the GPIO pin has

a High−Z state where the impedance of the High−Z state is

larger then 2 M

W the switch will recognize the High−Z state

and disable the switch. If the system does not have GPIO that

supports High−Z state, the user can utilize 2 MOSFETs or

a Logic Device to achieve the same result.

For GPIO

The SEL pin function below:

considered as Logic High

be consider as Logic Low

will be consider as float/High−Z

System Timing Diagram

Figure 3. System Timing Plot

VDD

HSD±

HSD1±

HSD2±

SEL

UVLO

HSD± = HSD1±

4V

SEL = L

SEL = H

HSD± = HSD1±

HSD± = HSD2±

3V

HSD± = HSD2±