Supercapacitors for reliable backup power in embedded systems
From Samuel Nork’s article “Supercap backup circuit provides reliable uninterrupted power”
Temporary backup power is a common requirement for a wide range of applications whenever the main power source is suddenly unavailable. Examples include data backup applications ranging from servers to solid-state drives, power fail alarms in industrial or medical applications, and a host of other “dying gasp” functions where orderly power-down must be assured and system status communicated to a powered host. In the past, these types of high reliability systems used batteries to provide an uninterrupted power source whenever the main supply of power was inadequate or unavailable.
However, many trade-offs accompany battery backup, including long charge times, limited battery lifetime and cycle life, safety and reliability concerns, and large physical size. With the advent of high value electric double layer capacitors, better known as supercapacitors, alternate backup architectures may be employed which eliminate many of these trade-offs.
Supercap charger and backup control circuit using LT3350
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