TPS6594-Q1: PDN-0B: BUCK3_VOUT_n

Masatoshi Oguri

Part Number: TPS6594-Q1

Hello,

In the Table 5-3 in p.15 of user guide for PDN-0B, BUCK3_VOUT_n of 1212 has a specific value of 1.10V as shown below. It looks meaningful at 1,10V, although it will be ignored in multiphase operation. Does it actually has a meaning, or any value is OK? I guess 0.3V for BUCK3/4 of 1111 could be any value as long as it is within acceptable limits.

Thank you.

Regards,

Oguri

over 4 years ago

+1 Chris Sterzik over 4 years ago

TI__Guru 67551 points

Hello,

When BUCK3 and BUCK4 are used in a multiphase configuration there feedback pins can be used separately as monitors. In the PDN-0B the BUCK3 feedback pin FB_B3 is used to monitor the 1.1V external regulator voltage, VDD_DDR_1V1.

https://www.ti.com/lit/ds/symlink/tps6594-q1.pdf#page=52

https://www.ti.com/lit/ug/slvuc32/slvuc32.pdf#page=5

Regards,

Chris

0 Masatoshi Oguri over 4 years ago in reply to Chris Sterzik

TI__Expert 4780 points

Hi Chris,

I would like to make further question.

Is the voltage configuration for BUCK2 necessary for 3/4 phase operation? In PDN-0B, BUCK2_VOUT_1/2 for 1212 and BUCK2_VOUT_1 for 1111 are configured as 0.8V. But I think those settings are ignored in 3/4 phase operation. Are they necessary?

Thank you.

Regards,

Oguri

+1 Chris Sterzik over 4 years ago in reply to Masatoshi Oguri

TI__Guru 67551 points

Hello,

You are correct. The output voltage configuration is determined by the primary BUCK and setting BUCK2_VOUT_1/2 is not necessary.

10.3.2.1.4 Multi-Phase Buck Regulator Configurations

...The following slave registers are ignored:

• BUCKn_CTRL register, except BUCKn_VMON_EN and BUCKn_RV_SEL

• BUCKn_CONF register

• BUCKn_VOUT_1 and BUCKn_VOUT_2 registers

• BUCKn_PG_WINDOW register

• Interrupt bits related to the slave buck, except BUCKn_ILIM_INT, BUCKn_ILIM_MASK andBUCKn_ILIM_STAT

https://www.ti.com/lit/ds/symlink/tps6594-q1.pdf#page=51

Regards,
Chris

Power management

Power management forum

TPS6594-Q1: PDN-0B: BUCK3_VOUT_n