within a system. By setting the T/F pin high, the LM3551/2

will allow the current to flow through the flash LED while still

maintaining the fixed output voltage rail. The flash current is

set by R

0.36

Ω , and should not exceed 500mA. The total usable

output current is dependent upon the output voltage se-

lected. If the dual-mode configuration is used, the FTO pin

should be grounded to prevent the voltage rail from being

shutdown at an unwanted time.

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