Advantages of eFuse | Disadvantages of eFuse
This page covers advantages and disadvantages of eFuse and its basics. It mentions benefits or advantages of eFuse and drawbacks or disadvantages of eFuse.
There are three main types of over current protection devices
in electronic industry.
• One shot fuses
• PTC (Positive Temperature Coefficient) resettable fuses
• eFuses (Electronic Fuses)
What is eFuse?
An IC protection solution which overcomes limitations of discrete components based circuit protection is known as eFuse. It consists of FET which limits currents and/or voltages within safe limits during faulty conditions.
The eFuse device enables various functions to protect the system against various conditions such as inrush current, over current, reverse current, reverse polarity over voltage and short circuit faults.
Image Courtesy : Texas Instruments
The eFuse requires very few external components such as resistor and capacitor which offers current limiting and output voltage ramp rate setting respectively.
The operating principle of eFuse is different than one shot or PTC fuse types. The eFuse measures current flowing in the circuit and turn off internal switch when current exceeds specified limit. It does not limit current based entirely on heating unlike other protection devices.
The popular eFuse manufacturers include Microsemi (Now Microchip), ON semiconductor, Toshiba, TI, STMicroelectronics etc.
Benefits or advantages of eFuse
Following are the benefits or advantages of eFuse:
➨Due to less external components requirement, it saves board space. It is compact and completely integrated solution.
➨It offers robust protection compare to discrete component based protection circuit.
➨The eFuses are semiconductor ICs and hence offers rapid response during short circuits.
➨It performs well over wide temperature range with minimal changes in its parameters.
➨There is no change in its "ON resistance" even after faulty conditions in the circuit.
➨It blocks the reverse current.
➨Due to recent semiconductor advancements, they are available at lower cost and in reduced sizes.
Drawbacks or disadvantages of eFuse
Following are the drawbacks or disadvantages of eFuse:
➨It houses more terminals. Basic architecture of efuse consists of three terminals viz. input, output and ground.
➨It requires bias current to operate.
➨It is complex in construction. Advancement in semiconductor domain has reduced its size.