Hello
We want to use tps65721 in our future products. Our main goal is powering a wearable device that feeds from a rechargable li-ion battery. We know that the device can be turn on/off by writting on the hold-dcdc and hold-ldo pins with the processor chip. However, we want do this mechanism physically and independent of processor chip. For now, we have found following solutions:
1- connect PB-IN to a slide switch. The hold pins connects to ground. Connecting PB-IN to ground turns the device on (should remain in this state the entire time the device is on) and connecting this pin to Vsys turns it off.
2- Use a T-flip flop to convert the trigger pulse to a high/low signal after attaching PB-IN to a push button. In this case, the result is similar to that of a slide switch.
Question1: Does keeping PB-IN in the low state for a long time cause problems?
Question2: Is there another way to turn the PMIC on/off? PB-IN and hold pins could be handled by a subcircuit, for example.
Question3: In the charging state, the processor shouldn't be powered on since it's not connected to the body. Is there a way to prevent the processor from powering up? Adding another switch or push button is not desirable.
Thanks
Vahid foroutan
