Infineon's 1EDN7550 and 1EDN8550 Gate Drivers to Solve Ground-shift Issues in SMPS

Published  September 13, 2018   0
S Staff
Infineon's 1EDN7550 and 1EDN8550 Gate Drivers to Solve Ground-shift Issues in SMPS

When a power MOSFET is switched on or off in a switched-mode power supply (SMPS), parasitic inductances cause ground shifts, which can lead to uncontrolled switching of gate driver ICs. Sometimes it may even result in electrical overloading of power MOSFETs and failure of SMPS. Infineon Technologies offers the 1-channel low-side gate driver ICs 1EDN7550 and 1EDN8550 in order to address the problem. Both the gate drivers, belonging to the EiceDRIVER™ family and are used in industrial, server and telecom SMPS as well as wireless charging applications , telecom DC-DC converters and power tools; have truly differential control inputs and can effectively prevent false triggering of power MOSFETs.


The EiceDRIVER 1EDN7550 and 1EDN8550 are unaffected to static ground offsets up to ± 70 V, and safe operation is guaranteed at dynamic ground offsets of up to ± 150V, without having to cut ground loops. Since the gate driver ICs have truly differential inputs, only the voltage difference between the two inputs is decisive for the switching behavior of the gate driver IC. The 1EDNx550 EiceDRIVER are ideally suited for controlling power MOSFETs with Kelvin source contact. Moreover, the gate driver ICs provide plenty of robustness against ground shifts due to parasitic source inductances of the power MOSFET. Compared with galvanically isolated gate driver ICs, these single-channel low-side gate driver ICs are more space-efficient at lower cost against to traditional solutions.


The 1EDNx550 family offers a cost-effective solution for applications where the distance between a control IC (providing the control signals to the gate driver IC) and the gate driver IC is greater than usual. This may be due to product design requirements, printed circuit board technology of choice or daughter card concepts. What these constellations have in common is that parasitic ground inductances are the cause of ground shifts between the control IC and the gate driver IC. The 1EDNx550 family provides an effective solution to these challenges and reduces product development times.


Infineon's 1EDNx550 low-side gate driver family is available in a SOT-23 6-pin package. Compared to traditional solutions, it enables higher power density, reduced product development effort at a lower cost.