Datasheet LTC3415 (Analog Devices) - 10

LTC3415
OPERATION
other by programming the PHMODE pin of each LTC3415 Refer to Figure 2 for confi gurations of 2-phase, 3-phase, to different levels. For example, a slave stage that is 180 4-phase, 6-phase and 12-phase operation. degrees out of phase from the master can generate a A multiphase power supply signifi cantly reduces the amount CLKOUT signal that is 300 degrees (PHMODE = 0) away of ripple current in both the input and output capacitors. from the master for the next stage, which then can gener- The RMS input ripple current is divided by, and the effective ate a CLKOUT signal that’s 420, or 60 degrees (PHMODE ripple frequency is multiplied by, the number of phases used = SVIN/2) away from the master for its following stage. (assuming that the input voltage is greater than the number (420) 0 120 240 60 180 300 +120 +120 +180 +120 +120 CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT SV PHMODE PHMODE S PHMODE IN VIN PHMODE PHMODE PHMODE 2 PHASE 1 PHASE 3 PHASE 5 PHASE 2 PHASE 4 PHASE 6 3415 F02d
Figure 2d. 6-Phase Operation
(390) 0 90 180 270 30 +90 +90 +90 +120 +90 CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT SVIN SV SV SV PHMODE IN PHMODE IN PHMODE PHMODE IN PHMODE 2 2 2 2 PHASE 1 PHASE 4 PHASE 7 PHASE 10 PHASE 2 (420) 120 210 300 60 150 +90 +90 +120 +90 +90 CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT CLKIN CLKOUT SV SV SV SV IN PHMODE IN PHMODE PHMODE IN PHMODE IN PHMODE 2 2 2 2 PHASE 5 PHASE 8 PHASE 11 PHASE 3 PHASE 6 3415 F02e 240 330 +90 CLKIN CLKOUT CLKIN CLKOUT SVIN SV PHMODE IN PHMODE 2 2 PHASE 9 PHASE 12
Figure 2e. 12-Phase Operation
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