Test setup and performance summary

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Test setup and performance summary

11.1

Test setup

The PM6681A demonstration board has the following input/output connections:

– 1.5 V SMPS output through J4-J13 (OUT1+ and OUT1-)

– 1.05 V SMPS output through J1-J12 (OUT2+ and OUT2-)

– 3.3 V linear regulator output through LDO_ADJ - J10

– 5 V linear regulator output through LDO5 - J3 (LDO5)

and two active loads should be connected respectively to OUT1+, OUT1- and

OUT2+, OUT2-.

Figure 7.

Setup connections

11.2

Power-up

As shown in Figure 8, power-up starts when the input voltage is applied and the voltage on

the SHDN pin is above the device on threshold (1.5 V). First the LDO5 goes up with a

masking time of about 4 ms. If the LDO5 output is above the UVLO threshold at this time,

the device enters standby mode and the adjustable internal linear regulator LDO is turned

on.

AM01413v1