Components for smart electronic fuses
Fuses can be found in many applications with power electronics where they are protecting cabling, loads and voltage sources. So far mostly conventional lead fuses are in use. However, new semiconductors for smart electronic fuses enable smart circuit protection and have many advantages.
Advantages of electronic fuses
- Faster cut-off in case of short circuit which results in a shorter period of time with undervoltage conditions on the boardnet. This is important because the remaining ECUs would be forced into undervoltage reset with a subsequent power-on boot procedure during which they are not ready to operate. In consequence, vital driver assistance systems would temporarily not be available. Therefore electronic fuses are necessary to fulfil the demands of safe supply for safety critical systems.
- A smart fuse can be programmed in a way that it limits current to a max value before switching off some time later. With the current not exceeding the max value the voltage drop of the boardnet remains in the tolerance band in which all ECUs are still operational. Also stray inductances are loaded only with the limited current. This keeps voltage spikes and line ringing low when the fuse finally switches off.
- Without an air gap there is no arcing in the electronic fuse when the contact is made or broken. For this reason a silicon fuse is predestined for the use in hazardous areas with potentially explosive gases.
Table 1 below lists some smart switches, control ICs and other components for smart electronic fuses.
| Manufacturer | Family/Type | Type Designation | Features | Voltage Range / Current Range | Promoted as |
| DIODES | ZXCT1032 | single channel linear soft start OC detector OC disconnect Flag pin (diagnosis) external PMOS or PNP |
Current range adjustable via control voltage and shunt resistor 9.5V … 21V |
High-side inrush controller and electronic fuse | |
| Infineon | PROFET™+2 | BTS70xx | single, dual or quad channel, protection against OC, UV, thermal protection, absolute and dynamic diagnosis for open load in on and off state, short circuit to GND and battery proportional load current sense |
Automotive specification of 12V boardnet RDSon from 2.6mΩ … 66.5mΩ |
Automotive smart high-side switch |
| Infineon | EiceDRIVER™ | 2ED4820 | Dual channel gate driver, protection against OC, UV, thermal protection, diagnosis for open load in off state, load current sense |
48 V | 48 V smart high-side MOSFET gate-driver with SPI |
| Toshiba | TCKE7xx/80x/81x | single channel, adjustable OC, OV, inrush current limitation, latch-off or auto retry, reverse current blocking, small package |
4.4V … 18V, up to 5A, RDSon from 28mΩ … 53mΩ |
Electronic fuse | |
| Toshiba | TPD7xxx | TPD7107F |
single channel HS-gate driver, protection against output OC and OV, Currens sense out |
5.75V … 26 V | Automotive HS-gate driver for semiconductor relay |
| Toshiba | TPD7xxx | TPD7106F | single channel HS-gate driver, 150°C, rapid off drive | 4.5V … 27V | Automotive HS-gate driver for semiconductor relay |
| Vishay | SiP324xx | SiP32419, SiP32429, SiP32430 | single channel protection against OC, OT fault output pin auto restart after 150 ms (SiP32429) latch off (SiP32419) slew rate control |
6V … 28V 0.75A … 3.6A |
Smart load switch with programmable current limit and slew rate control |
High-Side gate drivers need external MOSFETs. Check out our FET-Parade of MOSFETs with lowest RDSon.
Last update: 20211021
