H- Bridge driving with opto-coupler based gate drivers

Henk,

Thanks for your questions. 

Henk Rode said:

can i drive 4 opto-coupler with one isolated power supply?

Yes, you can use a single isolated power supply for your devices. However, for the high-side drivers, you'll want to use a bootstrap circuit which, as the name suggest, bootstraps the high-side VGS using a diode and capacitor to bias the highside FET (shown in the figure below). 

Firstly, you asked about optocoupler-based gate driver recommendation. We have a line of opto-compatible gate drivers (UCC23xxx series) which are drop-in replacements for optocouplers and have key advantages (lower delay, longevity, superior part-part timing matching).  these are designed to be drop-in replacements for legacy designs that already used optocouplers.

Our opto-compatible drivers are only single output as well, so you would require 4 seperate gate drivers for your full-bridge.

One of our dual-channel isolated gate driversare great options if you're not restricted on using opto gate driver.

The difference in the implementation is shown in the figure below. With our opto-emulated parts, you split those dual output drivers down the blue line and you have to have 4 gate drivers vs 2. This figure also shows how the full H bridge is implemented with boostrap circuit to only use a single power supply.

If you're not restricted to using opto isolated gate driver, let me know and I can make other recommendations that might end up simplifying your design. But since you specifically asked about opto, i'll go ahead with the details on those parts. 

Henk Rode said:

 i need a suggestion opto-coupler that can work in 100kHz.

Depending on the design & the voltages you're working with, you'll either want to choose between basic & reinforced isolation options for our opto-compatible drivers and drive current. Thankfully, the ratings can help you make a quick decision on which one you need better. And all of these handle 100kHz without issue. 

Unless the voltage you are working with 

Basic Isolation:

UCC23313 - 4A / 5A, 3.75kVrms

Reinforced Isolation:

UCC23511 - , 1.5A / 2A, 5.7kVrms

UCC23513 - 4A / 5A, 5.7kVrms

Section 6.6 of their datasheets shows the isolation parameters that determine the selection of basic/reinforced based on your voltage, example below. 

VIORM is the maximum voltage the parts can are rated to handle repetitively.

Without knowing the information on your design, I can't say for sure. But unless you expect to see voltages approaching the 900V and need isolation >5kV, UCC23313 is the better option. 

As far as implementation in your circuit, the Section 10.2.2 in the datasheets of those parts i mentioned shows how to provide the signal to the gate driver. 

Also, we have a lot of good resources to help with designing with TI iso gate drivers, heres a few that can help get you started on this, including how to design the boostrap circuit

THIS Video Series on Gate Drivers. 

(Design) UCC23XXX EVM, which provides a basis for design with our opto-emulated gate drivers. 

(Videos) Isolated Gate Driver Introduction

(Video) H-bridge Fundamentals 

Full list of Reference designs w/ ISO gate driver

Bootstrap Circuitry Selection

I hope this answers your question. If it did, please click the green button. And let us know if you have more questions and we'll be more than happy to help with that. 

Best, 

Dimitri

Mikail,
You are absolutely welcome. 

You can use an isolated flyback to supply 15V to UCC23X1X like you mentioned, as this is above the 14V minimum output-side supply specified in the datasheet, and then this can be used with a bootstrap circuit to generate highside bias. Note that the voltage should be maintained above this limit.

The bootstrap circuit should work well for your application. The case where bootstrap would not work is when the highside FET needs to remain switched for arbitrary length of time, which is not the case for your application.

I hope this answers your question. If it did, please click the green button. And let us know if you have more questions and we'll be more than happy to help with that. 

Best,
Dimitri

You as well!