Do I Need two BTN8962A Here

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How are you?:D

Recently I am involving in a project about design a BDC driving board with BTN8962A which is from Infineon . BTN8962A is a half of H-bridge IC.

As we all know,BDC driving circuit is just like this:




In this picture,We set a High side MOS(QA) as Open,and set a High side(QC) and a Low side(QB) MOSes as close.We just have to ouput a PWM signal to control the speed of BDC.




However,I met some troubles when I use Infineon BTN8962,I found I could not do this unless using the INH pin as PWM signal input pin. ( In fact,this pin is sleep mode enable pin.It can close its MOS.)

Which pin should I set as PWM signal output pin? Do I need one more BTN8962A here in order to make a complete H bridge ?

Please give me some help !
Thank you in advance.
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7 Replies
User13978
Level 1
Level 1
Hi shay1995,

you are right in using the INH Pin as PWM input. This is the most efficient way to control the speed of you motor.
If you are using the BTN8962TA as a half bridge (as shown in figure 17 in the datasheet) it would be also possible to use the IN Pin for PMW. But in this case you force the motor to slow down when the LSS is active. So this will be pretty inefficient.

To build a full H-Bridge you need two of the BTN8962TA. You can find a reference design in figure 16 of the datasheet.

Have fun with it!
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Hi

I also have some questions about BTN8962 and just found this thread while i was searching for some answears.

So seeing above definately i will have to use INH pin as PWM input. Very clear... But my question is . What frequency , max voltage , should the PWM be. For example a 20ms period , 5v PWM will satisfy the BTN 8962?

Datasheet says that IN pin is used to enable either high side or low side of the half bridge depending on the IN pin Status. Right ... Question....this means that if IN pin is Low the LOW SIDE of half bridge will be enabled and if IN pin is HIGH , the HIGH side will be enabled?


Sorry if i posted dummy questions ... I'm 2nd year on collage.

Thank you..
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User270
Level 5
Level 5
5 solutions authored First solution authored
You can use up to 20kHz..25kHz PWM frequency. Refer to the datasheet page 23. Yes, the truth table on page 19 shows, with INH=low: IN=Low -> Output HSS=OFF and LSS=ON, IN=High -> Output HSS=ON and LSS=OFF.
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Right... Thx for replay... But


I do have another questions... How can i read with a microcontroller the IS output pin. I mean... I know howto read inputs etc but i need to know what should come as input.

What will the IS pin send as output based on the fault condition... My understanding is that it will just output high or low when any of the fault conditions will occur. Is that right?
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User270
Level 5
Level 5
5 solutions authored First solution authored
Connect a resistor with 1kOhm to pin IS and GND (pull-down). In case of an error the current IIS(lim) will be forced and you can read Verror=1kOhm*5mA=5V at Vs=13.5V.
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Thx... What will this help me for a full H bridge? If i get an error the motor will stop anyway so i don't get the reason why monitoring the IS pin.

Maybe there is a very good reason and as i'm a begginer i can't see it.. ?......
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JingN
Moderator
Moderator
Moderator
First like received First solution authored 25 replies posted
By measuring the voltage at IS pin, you can control the output current. The PWM frequency and duty cycle can be adjusted based on VIS.
If BTN8962TA is in a fault condition which is latched (e.g. overtemperature), MCU could recognize it by measuring VIS and reset the device.
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