Bypassing a D36V50Fx

Support Voltage regulators
1

I have a application using a D36V50Fx Regulator providing 9v to a inductive load, (sprinkler valve solenoid), as part of my startup sequence I want to bypass the D36V50Fx with 13v to help boost the solenoid to pull in, then later drop it to 9v to hold… is there a problem with me feeding 13v back through the output pin. or do I need to add an additional diode to the circuit to protect the regulator?

In this diagram the 9v is provided by the D36V50Fx
relay
thank you.

2

For a setup like this I would definitely recommend using the diode to avoid creating a short between your regulator output and your other supply voltage.

Alternatively, a simpler approach might be to supply your solenoid with a 13V PWM signal using an appropriate MOSFET or motor driver, then reduce the duty cycle to around 70%.

- Patrick