AN2815 Datasheet, PDF (18/42 Pages) STMicroelectronics – High-efficiency step-down controller

Getting started
8
Getting started
AN2815
The following step-by-step power-up and power-down sequences are provided in order to
correctly evaluate the PM6675AS demonstration board performance.
● Power-up sequence
– Working in an ESD-protected environment is highly recommended. Check all wrist
straps and ground mat connections before handling the PM6675AS demonstration
board
– Connect power supplies as shown in the PM6675AS demonstration board test
setup (Figure 12) and insert the meters in order to perform the desired
performance evaluation. Connect the scope-probes as desired
– Set the JP1 through JP5 jumpers in order to properly configure the PM6675AS
board (default position suggested). Set the SWEN-LEN switches to the on position
(upper position); Do not change jumper settings when the board is powered
– Set the V_CC supply to 5 V±5% and the current limit to 100 mA
– Set the V_IN supply to a voltage in the range 4.5 V to 36 V. An initial test at 24 V and
2 A current limit is suggested
– Set all the loads to 0 A
– Turn-on the V_IN supply
– Turn-on the V_CC supply
– Vary the V_OUT load from 0 A to 8 A
– Vary the L_OUT load from 0 A to 2 A to test source capability. If a different LDO input
is desired, connect the external rail as dashed in Figure 12 and remove the R6
resistor. All changes must be done when the board is not powered
– Vary VIN supply from 4.5 V to 36 V
● Power-down sequence
– Decrease L_OUT loads to 0 A
– Reduce V_OUT load to 0 A
– Decrease V_CC supply from 5 V to 3.8 V in order to test the UVLO
– Increase V_CC supply from 3.8 V to 5 V to restart the device
– Use the SWEN-LEN switches to test soft-start and soft-end on both outputs
– Turn-off the V_OUT load
– Turn-off the V_CC supply
– Turn-off the V_IN supply
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