• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 418 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CSD16408Q5: MOSFET as Switch Using Gate Driver

Pedaiah G
Prodigy 230 points
Part Number: CSD16408Q5

Hi,

I am using a gate Driver UCC27531DBV to drive the MOSFET CSD16408Q5.The simulation results were shown below w.r.t 3.3V and 0V Input Voltages to Gate Driver.

MOSFET having Vgs = 1.4V to 2.1V.

For the MOSFET to Turn-ON, Vgs > 1.4V provided. So, Output at Load (1 Ohm) ~ 5V.

For the MOSFET to Turn-OFF Vgs < 0V provided, But still MOSFET Turned - ON and Output at Load (1 Ohm) 4.235V.

Query:

1.How to Turn-OFF the MOSFET with Gate Driver in above Circuit ?

Note: I have Downloaded the Pspice Model from TI official Website.

Thanks and Regards,

Pedaiah G.

  • 0
    TI__Mastermind 38130 points

    Hello Pedaiah G.

    Thanks for your interest in TI FETs. TI specs threshold voltage at ID = 250uA, where the FET just begins to turn on. For this device, on resistance is specified at a minimum VGS = 4.5V. We do not spec or guarantee on resistance at VGS < 4.5V. When VGS < 0V, the MOSFET is in cutoff and there should only be a small leakage current, IDSS, which is specified to be <= 1uA at VGS = 0V and VDS = 20V. You are getting significantly more current than 1uA. Can you please share your simulation schematic with me.

  • 0 in reply to John Wallace1
    Prodigy 230 points

    Hello John,

    Thanks for your reply.

    Please Find the simulation schematics of MOSFET with Gate driver. Hope i have used proper Pspice Model.MOSFET SIMULATION.zip

  • 0 in reply to Pedaiah G
    TI__Mastermind 38130 points

    Hello Pedaiah G.

    Thanks for sharing your simulation. The drain and source terminals reversed and the body diode of the MOSFET conducts when it is off. The voltage you see at the load is 5V - VSD (body diode forward voltage). The attached zip file is the correct configuration. I believe the attached zip file will give you the desired results.

    MOSFET SIMULATION1.zip