LTM4616
APPLICATIONS INFORMATION
(420)
60
0
120
240
180
300
+120
+120
+180
+120
+120
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
PHMODE
PHASE 1
PHMODE
PHASE 3
S
VIN
PHMODE
PHASE 5
PHMODE
PHASE 2
PHMODE
PHASE 4
PHMODE
PHASE 6
4616 F02
Figure 2. 6-Phase Operation
(420)
60
0
120
240
180
300
+120
+120
+180
+120
+120
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
PHMODE
PHASE 1
PHMODE
PHASE 5
S
VIN
PHMODE
PHASE 9
PHMODE
PHASE 3
PHMODE
PHASE 7
PHMODE
PHASE 11
V
OUT1
LTC6908-2
OUT2
IN
(510)
150
(390)
30
90
210
330
270
+120
+120
+180
+120
+120
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
CLKIN CLKOUT
PHMODE
PHASE 4
PHMODE
PHASE 8
S
VIN
PHMODE
PHASE 12
PHMODE
PHASE 6
PHMODE
PHASE 10
PHMODE
PHASE 2
4616 F03
Figure 3. 12-Phase Operation
The LTM4616 device is an inherently current mode con-
trolleddevice, soparallelmoduleswillhaveverygoodcur-
rent sharing. This will balance the thermals on the design.
in Figure 17. Figure 19 shows a schematic of the parallel
design.TheFBpinsoftheparallelmodulearetiedtogether.
Input RMS Ripple Current Cancellation
Tie the I pins of each LTM4616 together to share the
TH
current. Current sharing is inherently guaranteed by the
current mode operation of the LTM4616’s DC/DC regula-
tors. Moreover, the accuracy of current sharing between
the two outputs is approximately 15%. To reduce ground
Application Note 77 provides a detailed explanation of
multiphase operation. The input RMS ripple current can-
cellation mathematical derivations are presented, and a
graph is displayed representing the RMS ripple current
reductionasafunctionofthenumberofinterleavedphases.
Figure 4 shows this graph.
potential noise, tie the I
pins of all LTM4616s together
THM
and then connect to the SGND of the master at the point it
connectstotheoutputcapacitorGND.Seelayoutguideline
4616fe
14
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LINEAR_DIMENSIONS [ Linear Dimensions ]
