Hello,
the datasheet-section of the "Differet Mode Operations" contains the confusing statement: In full bridge and half bridge modes, PWM_A controls half bridge A, PWM_B controls both half bridge B, etc.
In full bridge and half bridge modes, PWM_A controls half bridge A, PWM_B controls both half bridge B, etc.
Figure 6 shows an application example for full bridge mode operation.
What does this mean?
I interprete this sentence in the way, that at full bridge mode AND half bridge mode each Terminal Out (Out_A, Out_B, Out_C, Out_D) is fully independly controlled by its dedicated input-control-pin (PWM_A ... PWMD) in the manner
PWM_A = L --> Out_A = Gnd
PWM_A = H --> Out_A = Vdd
PWM_B = L --> Out_B = Gnd
and so on
But: If this is true, then where is the difference of half and fullbrigde control. It seems, that the controling logic of both modes is identical?!?!?!?!
Regards Wolf
Hi Wolf,
This is just my take on the documentation as I have not used the chip yet though we are planning on it. There seem to be typos and possibly some errors in the diagrams as well but I understand the funcitonality to be that
Full bridge mode :
PWM A - controls outputs A and B with output A being V+ and B being V-. PWM B would be at ground in this direction.
PWM B - control outputs A and B with output B being V+ and A being V-. PWM A would be ground in this state.
Same logic for PWM C and D relative to outputs C and D.
Parallel bridge mode
PWM A : controls both output A and B but with same polarity. V+ when high and V- when low
PWM B : controls both output C and D with same polarity
Half Bridge mode
Individual control over the outputs A, B, C and D using the individual PWM inputs A, B, C and D.
If this is wrong, could someone from TI please say so.
Cheers
Peter
ALL CONTENT AND MATERIALS ON THIS SITE ARE PROVIDED "AS IS". TI AND ITS RESPECTIVE SUPPLIERS MAKE NO REPRESENTATIONS ABOUT THE SUITABILITY OF THESE MATERIALS FOR ANY PURPOSE AND DISCLAIM ALL WARRANTIES AND CONDITIONS WITH REGARD TO THESE MATERIALS, INCLUDING BUT NOT LIMITED TO, ALL IMPLIED WARRANTIES AND CONDITIONS OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT OF ANY THIRD PARTY INTELLECTUAL PROPERTY RIGHT. NO LICENSE, EITHER EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, IS GRANTED BY TI. USE OF THE INFORMATION ON THIS SITE MAY REQUIRE A LICENSE FROM A THIRD PARTY, OR A LICENSE FROM TI.
Content on this site may contain or be subject to specific guidelines or limitations on use. All postings and use of the content on this site are subject to the Terms of Use of the site; third parties using this content agree to abide by any limitations or guidelines and to comply with the Terms of Use of this site. TI and its suppliers reserve the right to make corrections, deletions, modifications, enhancements, improvements and other changes to the content and materials, its products, programs and services at any time or to move or discontinue any content, products, programs, or services without notice.