LM5116: Correct Connection for RAMP Pin

Keith Keller

Part Number: LM5116
Other Parts Discussed in Thread: LM5117

Hello,

We're working on a new design using the LM5116 and we are seeing some differences in how the RAMP pin is connected:

Could you please let us know the correct connection? (3 images below)

Thank you, Keith

0 Ethan T over 4 years ago

Hi Keith,

The standard application is to have a ramp capacitor (Cramp) connected to the Ramp pin.

The pull-up resistor to VCC is recommended for higher output voltages (higher duty cycle) where additional slope compensation may be required.

The pull-up resistor to SW may be a typo or application I am not aware of. I will check with the product expert and get back to you.

Regards,

Ethan

0 Keith Keller over 4 years ago in reply to Ethan T

Hi Ethan,

Could you please comment on if RAMP should be connected to Vin or SW?

Thank you, Keith

0 Keith Keller over 4 years ago in reply to Keith Keller

Hello,

The answer to this question is:

The Rramp goes to VCC in the calc tool on line for the LM5116 and goes to Vsw for the LM5117 & this is the correct configuration.

Best regards, Keith

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