TPS3809I50DBVT IC Queries

vimal valand

Other Parts Discussed in Thread: TPS3809, TLV803

We had design a power supply board,for our design purpose we had use TPS3809I50DBVT as shown in attached file.The problem arrived that the second one TPS3809I50DBVT(U4) cannot give output & therefore can not drive two transistors, if we short the input & output of U4 that time both transistors works well.

I request you to kindly provide us your valuable suggestion for our design, so we can move forward with design phase.

over 6 years ago

0 Michael_DeSando over 6 years ago

TI__Genius 12630 points

Vimal,

So it looks like you are using TPS3809 which is a push-pull output topology as an open-drain device. You have pull-up resistors at the reset output but that is only required with open-drain devices. Please remove R17 and R16 in order to use each TPS3809 in the correct push-pull configuration.

-Michael

0 vimal valand over 6 years ago

Prodigy 50 points

We had already cheched by removing R16 & R17 but no change in output

0 Michael_DeSando over 6 years ago in reply to vimal valand

TI__Genius 12630 points

Vimal,

Push-pull devices are not know for being good multi-device drivers. I recommend switching to a device that actually is open-drain such as TLV803. The additional pull-up resistor with open-drain devices allow you to set the pull-up voltage if needed and use the pull-up resistor value to set enough current to drive the next device. For the TPS3809, it appears that the /RESET sink current during start up is larger than the supply current (for the next device).

-Michael

0 vimal valand over 6 years ago in reply to Michael_DeSando

Prodigy 50 points

Hello,

Thanks for your valuable response.

I will check our design with TLV803 device & then after inform you for our result.

0 vimal valand over 6 years ago in reply to vimal valand

Prodigy 50 points

Hello,

Parallel with swithing open drain device TLV803. Any other modification required for our design with TPS3809 for testing? because our team will decide to replace TLV803 device instead of TPS3809 for all this type application.

0 Michael_DeSando over 6 years ago in reply to vimal valand

TI__Genius 12630 points

Vimal,

I think switching to Open-drain is the correct solution. Please confirm if this worked or if additional support is needed. Thanks!

-Michael

Power management

Power management forum

TPS3809I50DBVT IC Queries