EVDD415 IXDD415 High Frequency Gate Driver IC Evaluation Board General Description The EVDD415 evaluation board is a general-purpose circuit board designed to simplify the evaluation of the IXYS/DEI IXDD415 gate drive IC, as well as to provide a building block for power circuit development. The IXDD415SI SO-28 package gate driver is factory-installed in the EVDD415. The board enables the user to drive MOSFETs in the DEI DE150 or DE-275 RF package types. The evaluation board design allows these MOSFETS to be attached to a heat sink, and in so doing the board assembly can be used as a ground referenced, low side power switch for both singleended and push-pull configurations. Circuitry for the TriState function is included on the evaluation board. Figure 1 is a photograph of the IXDD415 Evaluation Board loaded with an IXDD415SI driver and a DE275-102N06A MOSFET. The low level inputs are shown on the left side of the board. J1 is a TTL high true input connected to the INA and INB pins which control the on or off state of the power switch U2. E9 is a low true input connected to the ENA and ENB pins, which control the Tri-State output. E1 is the low voltage, (8-30V) power input connected to VCC-IN of the IC, (see Figure 3 below). Figure 2 illustrates the MOSFET mounting of a DE-Series MOSFET. The MOSFET is mounted on the back side of the PCB. Circuit Operation The schematic diagram for the evaluation board is shown in Figure 4. The control gate is applied to R4 then on the input pins 7 and 8 of the IC U1. This signal input is followed in time by the output pins 19 through 24 U1. Pins 1 through 4 and 11 through 14 U1 are attached to +VCC via a decoupling network comprised of R1, C1, C2, C3 through C10 and C13 through C16. Pins 5, 10, 15 through 18 and 25 through 28 U1 are attached to the circuit ground plane. This is the preferred arrangement of the bypassing for the Vcc input power. The enable pins 6 and 9 of U1 are attached to the drain of Q1. This device is used to level translate and provide an invert function for the Tri-State mode. The drain of Q1 is also attached to the gate of the MOSFET thru R9 and D1. In the Tri-State mode the turn off time of the power MOSFET is determined by the time constant of the input gate capacitance Ciss and the value of the resistor R9. See the IXDD415 data sheet for additional information on this mode of operation. The U1 output is available at pins 19 through 24 of U1. The board is designed to parallel the two outputs of the IXDD415 IC, generating up to 20A(1) of output current. The three output pins for each channel should always be paralleled to reduce circuit inductance, and to provide the current-carrying capability required for the high output current capability of the IXDD415. There are two test points on the board: E6 for Control and E7 for the Drain. These allow the user to easily attach an oscilloscope probe and the associated ground to the circuit to verify performance. The drain output section is designed to allow the user to install the load of choice as well as the type of high voltage bypassing. The Drain pad is labeled E7. The large pad to the right of E7 is intended for the Vds power supply connection. Surrounding the drain pad and the Vds pad is a power ground pad. In the circuit diagram this pad is labeled E8. Figure 1 - EVDD415 Evaluation Board DEI DE275-102N06A Device Installed In Low-Power Configuration For Illustration Purposes Only #4-40 Socket Heat Screw (Or Equivalent) 3 Inch-Pounds Max. Torque DE-Series MOSFET Belleville Washer Printed Circuit Board Heat Sink Thermal Compound Side View Metallic Substrate Heat Sink End View From Drain Side Figure 2 - EVDD415 Side Views Showing DE-Series Power Device Installed In A High-Power Configuration(2) INPUT FUNCTION J1 (SMB) Control Input - 3V into 1K Ohms E2, E4, E5, E8, E10 Ground E9 Enable, LOW = True, HIGH = Tri-State Mode E1 VCC input - 8V to 25V Figure 3 - Input Pin-Out Table Part Number EVDD415 ORDERING INFORMATION Installed Device Accommodates DEI DE-150 and DE-275 Series MOSFET Devices (1) Each output of the IXDD415 can provide 15A of current, but when both outputs are driven simultaneously, as with the EVDD415, the maximum output current should be limited to 20A. (2) For additional device installation instructions, see the technical note "DE-Series MOSFET Mounting & Installation Instructions" on the DEI web site at www.directedenergy.com/apptech.htm. Copyright © IXYS CORPORATION 2001 First Release EVDD415 Figure 4 - EVDD415 Schematic Diagram And Circuit Board Layout NOTES: 1) The schematic shows a DE275 MOSFET, however a DEI DE-150 or DE-275 package type may be installed on the EVDD415. The EVDD415 is provided without a MOSFET, so that the user can install the appropriate MOSFET for their application. Figure 5 - EVDD415 2.2ns (2V to 12V) Gate Rise Time CL=1000pF Figure 6 - EVDD415 Typical Gate Waveform CL=1000pF Figure 7 - EVDD415 Typical Output Waveform F=50MHz Burst, CL=1000pF For additional performance data and electrical waveforms, see the IXDD415SI Data Sheet on the DEI or IXYS web sites. Directed Energy, Inc. An IXYS Company 2401 Research Blvd. Ste. 108 Ft. Collins, CO 80526 Tel: 970-493-1901; Fax: 970-493-1903 e-mail: [email protected] www.directedenergy.com IXYS Corporation 3540 Bassett St; Santa Clara, CA 95054 Tel: 408-982-0700; Fax: 408-496-0670 e-mail: [email protected] www.ixys.net 2 IXYS Semiconductor GmbH Edisonstrasse15 ; D-68623; Lampertheim Tel: +49-6206-503-0; Fax: +49-6206-503627 e-mail: [email protected] Doc #9200-0232 Rev 2