A relatively simple circuit has been shown which
improves the no load voltage accuracy any DC - DC
converter. In addition it provides the droop resistance
characteristic which taken together with the improved no
load voltage accuracy provides good current sharing
bctiveen the modules wired together in redundant. high
availability systems. As required no single point of failure
exists. In addition with no interconnecting paralleling
vires noise sensitivity is lowered with the bonus that
module .enders can be mixed thereby precluding the
nccessih for a single source for modules. The concept has
been implemented and shipped in several systems each
in,olving "hot swapping". There have been as few as two
con.erters in parallel and as many as 96 (so far). The 96
module system provided -48 Volts at 300 Amps in three
rack trays. The configuration grouped the modules in sets
of four giving a 21 + 3 redundancy system. Three cards
(or three modules) had to fail before the 300 Amp load
capability [vas impacted.