I want to protect some microprocessor equipment ( 5.0v, max 700mA ) which is powered by usb cell phone type chargers from damage due to such things as polarity reversal, over-voltage, power surges etc. I don't want a voltage drop (such as from a series diode) and it should sustain, without damage, a prolonged fault condition.
Is it simply enough to have a polyfuse in series with power input and afterwards a unidirectional transient voltage supressor (with 5.0v standoff voltage) reversed across power input ?
1PMT5.0AT1G 5.0v unidirectional TVS diode
LITTELFUSE 60R050XPR Polyfuse 1A tripping current. http://uk.farnell.com/littelfuse/60r050xpr/resettable-fuse-60vdc-40a-radial/dp/2383313
Follow up question: Under what circumstances would a bi-directional TVS be used in this scenario ?