TPS22975EVM: Threshold of ON pin

Vincent Chen64988

Part Number: TPS22975EVM
Other Parts Discussed in Thread: TPS22975, TPS22954

Hi Team,

My customer is evaluating EVM board and found turn on threshold is about 0.8V not like datasheet showed the VIH is 1.05V(TA< 85°C). The customer test condition as following.

Customer added a divided resistors on ON pin in EVM and the purpose is to tune on TPS22975 when VIN arrive 4.5V.

Both VIN and Vbias are connected to 5V supplier, thee Von pin divided resistors are 12K and 4.3K and one terminal of upper resistors(12K) is connected to 5V supplier. When 5V supplier raises and the ON pin voltage closes to 0.8V, TPS22975 turns on.

Vin and Vbias are powered from 5V supplier first, then increasing ON pin voltage slowly and when it achieve 0.8V then TPS22975 was turned on.

Could team help to comment on this case.

Thanks very much.

Vincent Chen

over 5 years ago

0 Shreyas Dmello over 5 years ago

TI__Mastermind 32650 points

Hi Vincent,

This is expected. The V_ih for this device refers to the voltage above which the device will turn on for control.

The V_il refers to the voltage under which the device will turn off for control.

Voltages between V_il and V_ih are not reliable to control the device but the device behavior is not defined between these voltages.

0 Vincent Chen64988 over 5 years ago in reply to Shreyas Dmello

TI__Expert 4480 points

Hi Shreyas,

Thanks a lot for the comment. For precisely controlling the turn on timing purpose, customer tend to choose TPS22954.

Vincent Chen

Power management

Power management forum

TPS22975EVM: Threshold of ON pin