TPS7A4700/about data sheet Fig14

Tsukui Yusuke

Guru 21930 points

Hi Team,

Could you tell me about TPS7A4700 data sheet graph.
Customers want to know more Vdo=500mV data in data sheet Fig14.
Please tell me the location data has disappeared(Vdo=500mV).

Best Regards,
Yusuke/Japan Disty

over 8 years ago

0 Ryan Eslinger over 8 years ago

TI__Guru 55940 points

Hi Yusuke-san,

The green line appears to be covered by the orange line in the 10Hz - 100Hz and 1M to 10M decades.

Very Respectfully,
Ryan

0 Tsukui Yusuke over 8 years ago in reply to Ryan Eslinger

Guru 21930 points

Hi Ryan-san,

Thank you for your information.

0 Ryan Eslinger over 8 years ago in reply to Tsukui Yusuke

TI__Guru 55940 points

Hi Yusuke-san,

From 600kHz on, The PSRR is dominated by the output capacitor. This is why all of the lines have merged together in this range.

Very Respectfully,
Ryan

0 Tsukui Yusuke over 8 years ago in reply to Ryan Eslinger

Guru 21930 points

Hi Ryan,

Thank you for your advice.
But,Customer want to know Vdo=500mV PSRR data.
Could you tell me about green line data like another Vdo.

Best Regards,
Yusuke/Japan Disty

0 Ryan Eslinger over 8 years ago in reply to Tsukui Yusuke

TI__Guru 55940 points

Hi Yusuke-san,

At this frequency range, the capacitor is dominant and the LDO is contributing very little to PSRR. The PSRR for this frequency will be dependent on whatever capacitor the customer selects. You can use Vdo = 300mV (blue line) to see what the capacitor we used contributed to PSRR.

Very Respectfully,
Ryan

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TPS7A4700/about data sheet Fig14