Other Parts Discussed in Thread: LM74800-Q1, LM7480-Q1, TPS24740
Hello:
I am interested in using the TPS2411 for power OR-ing our device which must meet a special case. I wanted to ask TI for directions on how to use the TPS2411 for this case (although we are open to other suggestions).
We have an UPS that outputs the power of a DC power supply or a 12V battery - preferring the DC power supply over the battery. The UPS can be put in sleep mode - however when this happens, it cannot turn on again until the user re connects the DC power supply. We have a special case in which we want to start the UPS again without connecting the power supply (for emergency purposes). For this, we need to briefly apply the voltage of the battery into the input of the UPS (where the DC power supply is) in order to turn ithe UPS on. On testing we have determined that the UPS just briefly needs a voltage on the node to turn on. The UPS on worst case scenario can deliver up to 100W - but it wont need to deliver much power when the system is recently turned on.
Because of this, we want to have a power OR that can allow us to apply the DC power supply or the battery voltage when we push a button into the input of the UPS. Our ideal solution would do the following:
When the DC power Supply is present it should always choose this input. DC Power Supply of 14.25V
When the DC Power supply is absent, it should choose the battery voltage Only while a button is pressed! Otherwise all power should be disconnected. Battery voltage: 10V-14V
I wanted to use the TPS2411 since it allows for logical control as well as use dual mosfets to protect power supplies when the selected voltage is the lowest one (as it is in the battery case).
My questions are:
1.) Does TI have a SPICE model for the TPS2411 so we can test the circuit before we implement?
2.) We wanted to use the mosfets Si7137DP. How can we determine the VGS that the system will generate to determine how much is the mosfet switched on?
3.) Do you have a recommended circuit to achieve the previous implementation?
3.) Do you perhaps have any recommendation on how to achieve our goal? Maybe another method comes into mind. (Sadly we cannot modify or change the UPS).
Thank you for your time!
