LMZM33603: About efficiency curve data

Tsukui Yusuke

Guru 21930 points

Part Number: LMZM33603
Other Parts Discussed in Thread: LMZM33606, LMZM33606EVM

Hi,

Could you tell me about efficiency curve data Fig1 ?
Is this data in forced PWM mode?

If the data includes pulse skip,
Do you have efficiency data for fixed frequency mode using the sync pin?

Best Regards,
Yusuke

over 4 years ago

0 Andy Chen over 4 years ago

TI__Mastermind 27045 points

Hi Tsukui,

The eff curve is for force PWM mode.

0 Jimmy Hua over 4 years ago in reply to Andy Chen

TI__Mastermind 47060 points

Hi Yusuke-san,

As Andy as pointed out, the eff curve is for FPWM mode. I wouldn't expect the efficiency behavior to change whether it is through RT mode or SYNC mode. As long as the external frequency is stable an fixed, I would expect similar performance for fixed frequency at RT mode and SYNC mode.

Regards,

Jimmy

0 Tsukui Yusuke over 4 years ago in reply to Jimmy Hua

Guru 21930 points

Jimmy-san,

Thank you for your kind support.
Please let me ask one more question.

Does this device have PFM mode?
If you have PFM mode,
Do you have PFM efficiency data?

Best Regards,
Yusuke

0 Jimmy Hua over 4 years ago in reply to Tsukui Yusuke

TI__Mastermind 47060 points

Hi Yusuke-san,

The LMZM33603 power module only operates in "Active Mode" which is basically FPWM(Section 7.4.1). This is in continuous conduction mode with fixed switching frequency. There is no PFM option for the LMZM33603.

If you are interested in evaluating a power module with PFM that can handle 3A current, you may be interested in the LMZM33606 power module. Figure 1 and Figure 2 of the LMZM33606 datasheet provides insight on what to expect from using the LMZM33606EVM in either FPWM or PFM mode.

Regards,

Jimmy

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LMZM33603: About efficiency curve data