Datasheet

MAX5060/MAX5061
0.6V to 5.5V Output, Parallelable,
Average-Current-Mode DC-DC Controllers
22 ______________________________________________________________________________________
Parallel Operation
For applications requiring large output current, parallel
two or more MAX5060s (multiphase operation) to
increase the available output current. The paralleled
converters operate at the same switching frequency
but different phases keep the input capacitor ripple
RMS currents to a minimum. The MAX5060 provides
the clock output (CLKOUT), which is 180° out-of-phase
with respect to DH. For the MAX5061, the out-of-phase
clock can be easily generated using a simple inverter
and driving it from the LX node. Use CLKOUT to drive
the second DC-DC converter to double the effective
switching frequency and reduce the input capacitor
ripple current (see Figure 10).
To drive multiple converters out-of-phase, use a delay
circuit to set 90° of phase shift (4 paralleled converters),
or 60° of phase shift (6 converters in parallel). Designate
one converter as master and the remaining converters
as slaves. Connect the master and slave controllers in a
daisy-chain configuration as shown in Figure 11.
Choose the appropriate phase shift for minimum ripple
currents at the input and output capacitors. The master
controller senses the output differential voltage through
SENSE+ and SENSE- and generates the DIFF voltage.
Disable the voltage sensing of the slaved controllers by
leaving DIFF unconnected (floating). Figure 11 shows a
typical application circuit using four MAX5060s. This cir-
cuit provides two phases at a 12V input voltage and a
0.6V to 5V output voltage range.
V
IN
V
IN
CSP
DH
LX
DL
RT/SYNC
PGND SGND CLKOUT
CSN
SENSE-
EAOUT
SENSE+
MAX5060
V
IN
V
OUT
CSP
DH
LX
DL
PGND SGND
CSN
LOAD
RT/SYNC
MAX5060
DIFF
EAN
IN
EAOUT
DIFF
EAN
IN
Figure 10. Parallel Configuration of MAX5060