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TPS2834: Regarding TPS2834,TPS2835 and TPS51601A

Part Number: TPS2834
Other Parts Discussed in Thread: TPS2835, TPS51601A

Dear TI team,

Good evening.

We need half bridge gate driver which supports 2Mega Hz switching frequency, 20V Vgs(gate to source voltage) and Maximum 1.2A output current support.

Is below drivers supports 2 Mega Hertz switching frequency,

1.TPS2834

2.TPS2835

3.TPS51601A

If there is any other half bridge drivers according to our requirement,kindly suggest.

Thank you,

Caliber

  • Thank you for reaching out on E2E. 

    Due to the thanksgiving holiday in the US responses will be delayed, but our expert on this matter will get back to you early next week.

    Thank you for your patience.

    Regards,

    Daniel

  • Hello Caliber,

    The main issue with high frequencies is that they cause the device to dissipate more power and heat up. And extremely rough calculation is that:

    P = Fsw * VDD * Qg

    This power multiplied by the junction to ambient thermal resistance gives an estimate of how much the part will heat up. Since you have a very high Fsw, and a very high VDD, you will need to have a very small Qg FET in order to not exceed the thermal limits of the driver. I don't know what FETs you are using so I cannot say for sure whether it can operate at 2MHz.

    One of your requirements was to have a 20V Vgs voltage, I do not believe any of the drivers listed here actually support that. The TPS2834/5 only supports up to 15V and the TPS51601A only does 5V. The 28/30V listed in those datasheets refers to the input voltage of the buck converter system, not the Vgs voltage from the driver.

    Some of our 600V drivers (like UCC27712) meet the Vgs requirement, but will struggle with the 2MHz frequency based on the Vgs you want. Another possibility is to use a low side driver like UCC27624/614 in a half-bridge configuration, which has some limitations but may work for you. If you could use a different FET that needs a lower Vgs, I believe that could open a lot more options for your system, but as it is the options are pretty limited. Let me know if you have any questions.

    thanks,

    Alex M.

  • Dear Alex,

    Good morning.

    Thank you for your reply.

    We need half bridge gate driver which supports 2Mega Hz switching frequency, 20V Vgs(gate to source voltage) and Maximum 1.2A output current support.

    As we are looking for alternate options,we can drive the gate driver from 3.3V to 5V(Input PWM signal) at 2Mega Hz and Vdd(or Vcc,supply voltage) of driver also should support 5V and maximum 1.2A output current support.

    If there is any driver supports above criteria,kindly let us know.

    We also work on your suggested parts in your previous reply.

    Thank you very much for your reply.

    Thank you,

    Caliber

  • Hello Caliber,

    Okay, with this VDD level there are quite a few drivers that should be suitable. Just to clarify, you need the driver to be able to drive at 5V? Here is a quick filtered list of all the parts that would be reasonable choices from TI.com. A few of these are rated at just above 5V, if you need exactly 5V, use this list. Here are basically the main categories you can pursue:

    • Dedicated Buck drivers

    Like the ones you mentioned in the first post. These drivers are designed to run in a synchronous buck configuration and usually have some extra features that help them in this purpose. Particularly, the TPS28225 looks like a solid choice, but I do not know the details of your system so I cannot say for certain. 

    • GAN drivers

    GANFETs and drivers are popular for high-frequency switching applications. The two options here are the LMG1210 and the LM5113-Q1. These can be used with a low Vth MOSFET or a GANFET to reach very high frequencies, but are going to be a bit pricier. These are good for GAN because they internally regulate the voltage to ensure that exactly 5V is applied to the gate of the FET. 

    • Other half-bridge drivers

    These tend to be more adaptable to be used in a variety of applications, including synchronous buck converters. Most of them are controlled by two inputs independently rather than by a single PWM input. 

    Let me know if you are interested in more details about any of the drivers. I can't go into detail for all of them, but if you find one you are interested in I can answer any questions. As a side note, I filtered the table to include only packages with good thermals, as that will be important to reaching 2MHz operating frequency. So some drivers that only come in packages like SOIC are not shown. I also did not filter anything based on the input voltage threshold. I see you have a 3.3V to 5V input signal. I believe all of the drivers here should be able to operate with that signal. Let me know if you have any questions.

    thanks,

    Alex M.