Wurth Unveils a Series of SMT Transformers for SiC MOSFET Gate Drivers

Low leakage inductance, along with capacitances between the windings as low as 6.8 pF, combine to provide high common-mode transient immunity for gate driver systems. 

 

The WE-AGDT series. Image courtesy of Wurth

 

The WE-AGDT series comprises six transformers, each separately optimized for its own Wurth supplied reference design. The transformers feature two separate secondary windings, allowing for both unipolar (+15 V to +20 V, 0 V) and bipolar (+15 V, -4 V) output voltages. Input voltages of 9 to 36 V will supply a maximum output power of 3 to 6 W. 

 

Optimized for SiC Applications

Although optimized for SiC applications, the WE-AGDT will also serve to control power MOSFETS and IGBTs. When combined with an appropriate DC/DC converter, application to high-voltage GaN FETs designs are also possible. Indeed, Wurth provides a reference design for a 6 watt, galvanically isolated power supply for SiC MOSFET gate drivers. 

As per Eleazar Falco, Application Engineer at Würth Elektronik eiSos, "With the increasing spread of power semiconductor devices in silicon carbide technology, which work at switching frequencies above 100 kHz, their gate control requirements are becoming more and more sophisticated. With the WE-AGDT series and the associated reference design, we have developed a solution that is as innovative as it is reliable, allowing developers to easily implement a compact, efficient and flexible supply with up to 6 W output power." 

 

WG-AGDT Series Members

750318131

• VIN: 9 to 18 volts
• VOUT1: 15 volts
• VOUT2: -4 volts
• Power: 6 watts
• Interwinding capacitance (typical) 7.5pF
• Turns ratio: N1 to N2 to N3 is 2.25:3.5:1 

Schematic for 750318131. Terminal 1 is tied to 2, 4 is tied to 3. Image courtesy of Wurth.

 

750318114

• VIN: 9 to 18 volts
• VOUT1: 19 volts
• VOUT2: none
• Power: 6 watts
• Interwinding capacitance (typical) 6.8pF
• Turns ratio: N1 to N2 is 1:2

 

750317893

• VIN:  9 to 18 volts
• VOUT1: 19 volts
• VOUT2: none
• Power: 3 watts
• Interwinding capacitance (typical): 6.8pF
• Turns ratio: N1 to N2 is 1:2

 

Schematic for 750318114 and 750317893. Terminal 1 is tied to 2, 4 is tied to 3. Image courtesy of Wurth.

 

750317894

• VIN: 9 to 18 volts
• VOUT1: 15 volts
• VOUT2: -4 volts
• Power: 3 watts
• Interwinding capacitance (typical): 7pF
• Turns ratio: N1 to N2 to N3 is 2.25:3.5:1

 

750318208

• VIN: 18 to 36 volts
• VOUT1: 15 volts
• VOUT2: -4 volts
• Power: 5 watts
• Interwinding capacitance (typical): 7pF
• Turns ratio:  N1 to N2 to N3 is 3.5:3.5:1 

Schematic for 750317894 and 750318208. Image courtesy of Wurth

 

750318207

• VIN: 18 to 36 volts
• VOUT1: 19 volts
• VOUT2: none
• Power: 5 watts
• Interwinding capacitance (typical): 8.2 pf
• Turns ratio: N1 to N2 is 1:1.2

 

Schematic for 750318207. Image courtesy of Wurth

 

Applications

• SiC-MOSFET based power converter
• Uninterruptible power supplies
• Active power factor correction
• Solar inverters
• Battery chargers
• Industrial drives
• AC motor inverters
• Electric vehicles
• Powertrain
• Data centers

 

Physical and Environmental Concerns

• Reach approval: Conform or declared to (EC) 1907/2006
• RoHS approval: Compliant with 2011/65/EU and (EU) 2015/863 
• Compliant to IEC62368-1 / IEC61558-2-16 
• Isolation voltage up to 4 kV
• Halogen Free: Conforms to JEDEC JS709B and to IEC 61249-2-21
• Qualified to AEC-Q200 Grade 1
• The SMT mounted units measure, L x W x H:  11.3 by 10.95 by 11.94 mm