Data Sheet

LT7200S

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Rev 0

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and preventing excess current from being drawn from VIN. After the overcurrent or short is removed, the regulator

executes its soft-start function to prevent the output voltage from overshooting.

MODE/SYNC Operation

The MODE/SYNC pin is a multipurpose pin allowing both mode selection and operating frequency synchronization.

Connecting it to ground enables Burst Mode operation for superior efficiency at low load currents at the expense of

slightly higher output voltage ripple. When the MODE/ SYNC pin is tied to INTVCC or floated, forced continuous mode

operation is selected, creating the lowest fixed output ripple at the expense of light load efficiency. The LT7200S

detects the presence of the external clock signal on the MODE/SYNC pin and synchronizes the internal oscillator to

the phase and frequency of the incoming clock. The presence of an external clock places all regulators into forced

continuous mode operation.

Multiphase Operation

For output loads that demand more than 5A of current, different channels of the LT7200S outputs can be tied

together to run out of phase to provide more output current. Tying the PHMODE pin to GND forces 4-phase operation.

Tie it to INTVCC for 3-phase operation.

Table 4. PHMODE Configuration Table

PHASE

PHMODE = GND

PHMODE = INTVCC

Channel 1

0°

0°

Channel 2

180°

120°

Channel 3

90°

240°

Channel 4

270°

0°