LM5050-2: For Vin 5V application

Randy Chen

Part Number: LM5050-2
Other Parts Discussed in Thread: LM5050-1

Hi,

Customer would like to apply the Vin from the Type-C and the initial voltage is 5V. Customer would like to confirm if LM5050-2 operates at the Vin 5V condition? Is the OFF pin needs a logic high to turn off the external MOSFET at the Vin 5V condition?

Best regards,

Randy Chen

over 6 years ago

0 Karikalan Selvaraj over 6 years ago

TI__Genius 16305 points

Hi

Let me check and get back on this.

Regards,
kari.

0 Karikalan Selvaraj over 6 years ago in reply to Karikalan Selvaraj

TI__Genius 16305 points

Hi

Minimum operating input voltage Vin is 6V for LM5050-2.

For 5V operation, we recommend to use LM5050-1 or LM74700 devices.
LM74700 operates from 3.9V during startup and transients can go to 3.2V and still operate during these transients.

Regards,
Kari.

0 Randy Chen over 6 years ago in reply to Karikalan Selvaraj

TI__Intellectual 2295 points

Hi Kari,

Customer wants to let LM5050-2 not to operation in the Vin 5V condition. Should let OFF pin pull up to turn off the external FET? or doesn't matter? Can you please confirm if any leakage risk with the LM5050-2 operation in the Vin 5V condition?

Best regards,

Randy Chen

0 user3817758 over 6 years ago in reply to Karikalan Selvaraj

Prodigy 40 points

Hi Kari,

Due to we are using for Type-C application.

We only need the ideal diode power path when Type-C is 9V~15V, will LM5050-2 had risk when TypeC change from 5V=>9V~15V?

Regards,

Shi

0 Karikalan Selvaraj over 6 years ago in reply to user3817758

TI__Genius 16305 points

Hello Randy Chen,

At 5V, gate drive still works and will keep the MOSFET ON.
Please refer to the LM5050-2 datasheet Figure 8 in page 7 where Gate starts to rise above VIN at about 4V VIN.

Need to use external means to keep the OFF pin high after VIN goes below 5V.

Regards,
Kari.

0 Karikalan Selvaraj over 6 years ago in reply to Karikalan Selvaraj

TI__Genius 16305 points

Hello Shi,

If I understand your question correctly, when the input USB type C changes to 5V from 9V-15V range, you want to turn off the MOSFET?

Could you share more information about the application to let us support better.

Regards,
Kari.

0 user3817758 over 6 years ago in reply to Karikalan Selvaraj

Prodigy 40 points

Hi Kari,

The circuit as the attachment:

We only need the ideal diode turn on at 9V~12V condition, whether the circuit is OK for our application?

If typeC is 9V~12V => ideal diode=Turn on.

if typeC is under 9V => ideal diode=don't care

Thank you.

Regards,

Shi

0 Karikalan Selvaraj over 6 years ago in reply to user3817758

TI__Genius 16305 points

Hi

LM5050-2 has OFF pin which active high and would need more components to implement the turn off when input goes below 9V.

Could you consider using LM74700 for this application as it has EN (enable pin) that can used to turn off LM74700 when input is lower than 9V.

Regards,
Kari.

0 Karikalan Selvaraj over 6 years ago in reply to Karikalan Selvaraj

TI__Genius 16305 points

Hello Shi,

Could you let us know if LM74700 is suitable comparted LM5050-2?

Regards,

Kari.

0 Karikalan Selvaraj over 6 years ago in reply to Karikalan Selvaraj

TI__Genius 16305 points

Hello Shi,

If your question is answered, click "this resolved my issue" button at the end of the thread.

Let us know if you have more questions.

Regards,

Kari.

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LM5050-2: For Vin 5V application