Functional Description

The OCP0502A is a P channel MOSFET power distribution switch, which has adjustable current limit by the

ISET pin. In addition, the switch also features fast short-circuit response, under voltage lockout, over

temperature protection and reverse current protection.

Current Limit Threshold Setting

The OCP0502A provides adjustable current limit threshold which implemented by an external resistor from

ISET to ground, see figure 9. The current limit function can prevent the switch from over current condition. The

current limit value can be calculated using the follow equation:

The minimum current limit is 400mA，beyond 2A is forbidden.

Fast Short Circuit Protection

The OCP0502A provides short circuit protection function which can limit the output current to a safe level

without damaging the switch.

Under Voltage Lockout (UVLO)

The OCP0502A has under voltage lockout function which can disable the switch until the input voltage reaches

the UVLO threshold (typical 2.3V). The UVLO threshold has a 80mV hysteresis voltage which can prevent the

unwanted on/off cycling when there is noise on the input voltage.

Over Temperature Protection (OTP)

When the junction temperature exceeds 145℃, the internal OTP circuit turn off the power switch. There is a

temperature hysteresis 20 ℃,in other words, the OTP circuit can turn on the switch only if the junction

temperature is below 125℃.

Reverse Current Protection (RCP)

The OCP0502A includes the Reverse Current Protection(RCP) function, which can prevent the current to

Figure 17

PCB layout example

OCP0502A

Rev 2.0 :

www.leiditech.com

12.01.2019

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