Enquiry on 50ohm pulse generator

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Lucaris7
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5 replies posted 5 sign-ins First solution authored

Lucaris7_0-1645487145095.png

I want to use CoolGaN™ 600 V half-bridge evaluation platform featuring GaN EiceDRIVER™. However, this board expects a 50ohm pulse generator. I wonder whether it works well with my DSP F28379D. 

Lucaris7_1-1645487239223.png

 

 

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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Hi,

 

  Yes, you can do it. But as suggested , a proper signal / pulse generator has to be used accordingly. 

 

Regards,

Abhilash P

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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Hi,

 

    Thank you for posting on the Infineon community. 

According to the attached block diagram, I understood that you are using the following evaluation board, 

EVAL_1EDF_G1_HB_GAN. 

The input PWM signal for this board is intended to be connected through a Signal / pulse generator. Since when you go through the schematics of the evaluation board, it has 50ohm equivalent resistor on the input side. This has been designed considering that a MMCX coaxial connector is used. The PWM generator should be able to drive standard 5 V logic levels into a 50 Ω terminated load. This can be achieved only by using a signal / pulse generator.                                   

Abhilash_P_0-1645776720914.png

 

The microcontroller that you have suggested doesnt have a drive current sufficient to drive a 50ohm load. 

This might cause undesired inputs to the evaluation board since  low is considered when the input is ≤0.8 V and
high is when the input is in the range of 2-5 V  along with drive capability of 50ohm.

 

Regards,

Abhilash P

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Thank you. Can I remove the 50ohm resistor, or change to a larger resistor?

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Abhilash_P
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50 likes received 500 replies posted 250 solutions authored

Hi,

 

   Yes you can, But can you please let me know how you are planning to do it?
Adding resistors in parallel might reduce the equivalent resistance. And also if you change the resistor values correspond to that the pule / signal generator should be used.

 

Regards,

Abhilash P

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In the schematic, there are four 200ohm resistor in parallel to form the 50 ohm resistor. If I remove three of them, I can get a 200ohm resistance 

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Abhilash_P
Moderator
Moderator
Moderator
50 likes received 500 replies posted 250 solutions authored

Hi,

 

  Yes, you can do it. But as suggested , a proper signal / pulse generator has to be used accordingly. 

 

Regards,

Abhilash P

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