TPS62290: Response Time of EN Pin

Hi Kato,

The response time needs to be measured in the lab. Hence, I would come back with the measurement results by tomorrow.

Regards,

Febin

Hi Febin-san,

Thank you for your quick response.

I am looking forward to getting the update from you tomorrow.

Best regards,
Kato

Hi Febin-san,

Thank you for the information.

I have an additional quesiton, so could you please tell me the minimum pulse width for EN pin when the EN pin is asserted and de-asserted?
For example, does TPS62290 start up normally if the high level of the 10us pulse width is applied to EN pin ?
Additionally, does TPS62290 shut down normally if the low level of the 10us pulse width is applied to EN pin ?

Best regards,
Kato

Hi Kato,

May I please rephrase your question again, you are applying a 10us pulse width signal to the EN pin and expecting the device to turn on with its High and turn off during the transition to low level.  The above measurements are taken at specific conditions and can be used only as a reference. For the above measurement, Vout reaches the desired value much later than 10us, hence the device needs to have a higher pulse width signal to turn on. Similarly it will take more than 10us to turn off. Please provide more details if the answer does not clarify your question completely.

Regards,

Febin

Hi Febin-san,

Thank you for your response.

According to TPS62290 data sheet, the electrical characteristics related to "start-up time" and "Vout ramp-up time" are specified as follows.
So, is my understanding correct that TPS62290 cannot start up if the high pulse width for EN pin is less than 250us?
Additionally, if the high pulse width for the EN pin is 400us, TPS62290 can starts up but the output voltage cannot reach 100% of Vout. Then, TPS62290 shuts down. Is my understanding correct ?
On the other hand, how does the TPS62290 work when the TPS62290 is operating normally, for example, if the EN pin only goes to low for 40us?

I don't have the TPS62290EVM-279, so could you please actually check the operation using EVM?

Best regards,
Kato

Hi Kato,

Yes, you are right. 

Could you please clarify on what you mean by Normal operation? May I also know your Application and the conditions for which you would like to measure the EVM?

Regards,

Febin

Hi Febin-san,

Thank you for your support.

Could you please test the following scenario(case #1 ~ #3) with TPS62290EVM-279?
The VOUT behavior is what I would expect.

Best regards,
Kato

Hi Kato,

Please give me some time to check the EVM. I will come back with the measurement results next week.

Regards,

Febin

Hi Febin-san,

Thank you for your strong support.

I am looking forward to getting the measurement results from you early next week.

Best regards,
Kato

Hi Febin-san,

Thank you for your strong support.

When the output is no load, the output voltage is kept as the charge on C10 isn't discharged under the case 1 and case 3 even if EN is de-asserted to low.
Is my understanding correct ?

Best regards,
Kato

Hi Febin-san,

Thank you for confirming.

I understand.

Best regards,
Kato