Datasheet

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