TPS62816-Q1: sequence requirement between EN and VIn

Hi Given,

All key operation of device would be active after device supply reach to min input voltage and pin internal threshold. These the basic requirements for Enables pin.

There are some waveform for start up behavior on page 26 of the datasheet.

Best regards,

Tanvee

Hi Tanvee,

I'm Given's colleague. I'd like to update the question and add some background.

Question: In datasheet, typical application is VIN and EN setting up at the same time.  However, Customer use an MCU to control the EN of this device. there is some delay between VIN and EN rise. Please help to check if this is supported by this device. 

Background: There is another device in system from Infineon that has a bug. Some PWM waveform is sent out from SW pin in the scenario that EN is pulled low and VIN is set up. 

B&R

Lijia

Hi Lijia,

Thanks for background. 

It is okay to have delay between VIN and Enable pin. However, Is it possible to share the waveform shared by customer ? If it is confidential then I would like to take it offline. I would like to check the delay expected from MCU on EN pin.  

I will send you mail.

Thanks, Tanvee 

Hi Tanvee,

Checked with My customer, the delay between VIN setting up and EN rising edge is about 1~2 seconds.

They can't send the plot to me, is delay enough to analysis the risk?

B&R

Lijia

Hi Lijia,

Vin setting up and after 1/2 sec delay Enable will rise. Is my understanding correct? 

If this is the case then I don't see any problem. once Enable is on device key functions will be active.

Best regards,

Tanvee

Tanvee,

yes, your understanding is correct, thanks for the support!

B&R

Lijia