TPS650830: Confusion over switching frequency spec for VR3 and VR5.

Thomas Horwitz

Part Number: TPS650830
Other Parts Discussed in Thread: TPS650832

On page 30 of the TPS650830 datasheet there are to separate boxes labelled VR3_Controller switching frequency. What is the difference between the two? There are also 2 boxes labelled VR5_Controller switching frequency on page 40. Again what is the difference between the two?

over 8 years ago

0 Jayanth Kruttiventi over 8 years ago

TI__Intellectual 1360 points

Thomas,

Switching frequency on the controllers in TPS650830 depends on status on NVDC pin. For VR3, if NVDC pin voltage is set to 3.3V, the SW is 500KHz and when set to gnd, SW is around 800KHz. This option is available to change freq depending on input voltage and effciency and total solution size requirements.

Jay

0 Thomas Horwitz over 8 years ago in reply to Jayanth Kruttiventi

Prodigy 225 points

Directly above what you explained in your reply on page 30 is a box that says
VR3_Controller switching frequency PWM Mode (NVDC# = 3.3 V) 715 800 865 kHz
(TPS650830, TPS650832)
This contradicts what is in the box directly below.

0 Jayanth Kruttiventi over 8 years ago in reply to Thomas Horwitz

TI__Intellectual 1360 points

Thomas,

Please use the spec below. We will update the spec to remove the additional line.

Thanks,

Jay

0 Thomas Horwitz over 8 years ago in reply to Jayanth Kruttiventi

Prodigy 225 points

On page 6 and page 52 in the Switching frequency column of the tables show the frequencies for VR3 and VR5 to be 800khz/800khz instead of 500khz/800khz. Is this table correct? Also if I am not using a battery charger does it matter if the NVDC# pin is hi or low?

0 Jayanth Kruttiventi over 8 years ago in reply to Thomas Horwitz

TI__Intellectual 1360 points

I have tested the part in the lab today and confirmed the switching frequency on TPS650830. Table 3.1 is accurate where switching frequency of VR1 and VR4 are 500KHz/800KHz with NVDC 1/0. VR3 and VR5 SW are independent of NVDC pin and remain at 800Khz. Switching freq is dependent only on NVDC pin status and does not matter what input voltage is connected.

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TPS650830: Confusion over switching frequency spec for VR3 and VR5.