L6758A datasheet(29/42 Pages) STMICROELECTRONICS

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L6758A

Output voltage monitoring and protection

where I

MAX

is max. current requested by the processor (see Intel docs for details).

–

Adjust the defined values according to the bench test of the application.

–C

IMON

in parallel to R

IMON

can be added with proper time constant to prevent false

OC tripping.

Note:

This is the typical design flow. Custom design and specifications may require different

settings and ratios between the per-phase OC threshold and the total current OC threshold.

Applications with big ripple across inductors may be required to set per-phase OC to values

different than 110%: design flow should be modified accordingly.

7.2.2

Overcurrent and power states

When the controller receives an SetPS command through the SVI interface, it automatically

changes the number of working phases. In particular, the maximum number of phases

which the L6758A may work in >PS00h is limited to 2 phases regardless of the number N

configured in PS00h. The OC level is then scaled as the controller enters >PS00h, as per

Table 13.

7.2.3

Single-phase section

The single-phase section features the same protection as the multi-phase section. All the

previous relationships remain applicable upon updating variables, referencing them to the

single-phase section and considering it is working in single-phase.

Table 13. Multi-phase section OC scaling and power states

N (active phases in PS00h)

OC level in PS00h

OC level in PS01h, PS02h

1.550 V

0.800 V

1.050 V

1.550 V

L6758A датащи(PDF) 29 Page - STMicroelectronics