TPS92613-Q1: Using TPS92613-Q1 for driving resistive load

One more query why the typical application use diode at the input of supply.

As i do not need reverse polarity protection, and i may not need that? 

Hello Rahul,

What is your PWM frequency? What is the minimum duty cycle? Do you have linearity requirements? What is the input voltage range? 

This is a high current for a heating element. Would a switching device work for the application? These devices have a higher efficiency than our linear devices.

This might be able to provide a constant current to a resistive load. You will need to understand how the resistance changes as the load to ensure that the device will be able to maintain the required dropout voltage from IN to OUT.

If your current is 0.55A, the required dropout could be as high as 2V. This means that the output voltage would need to be less than 3 volts to ensure proper operation. In addition, the power dissipation of the device would be 1.1W and this would result in a junction to ambient temperature increase of 30C.

The diode is for reverse polarity protection.

Kind regards,

Nicholas Alexander

Hi Nicholas,

Thank you for your reply.

I expect the PWM frequency around. No specific requirement for linearity. Input Voltage range is 5V-15V.

Because of wider input range and to keep the resistive load value fixed I have also decided to go with the switching device.

And I need smaller size Switching device and found LM3405 would be good choice for the application.

Your thought on this will help me on this.

Thanks,

Rahul

Hello Rahul,

The LM3405 looks like a better option for this application. Other options could be the TPS92200 or the LM3405A. I am not the expert on these devices so I'll link you to the expert of these devices.

Kind regards,
Nicholas Alexander

Hi, Bella

Could you pls help to support this case?

Hi Rahul

For the Vin 5-15V, 0.55A@5V application, TPS92200 is recommended. It's synchronous buck LED driver with PWM dimming. 

Can you please share what's you end equipment? And what's the expected PWM frequency? Is the resistive load a fixed R or is there a I-V curve?

Thanks and best regards.

Hi Gui,

Thanks for your suggestion.

I was looking for high side LED driver as the other end of the resistive load is connected to ground terminal.

The load is pure resistor for heating purpose.

Thanks,

Rahul

Hi, Rahul

Our expert will reply you late.