Other Parts Discussed in Thread: TPS2662
Hi,
We are using the LM5069MM-2/NOPB in one of your new designs. The -2 variant is supposed to have auto restart functionality once the fault condition is removed.
In my design, the LM5069 is used for current limiting/short circuit cut-off in case of short circuits downstream from the LM5069 output. When I designed the circuit, I used the calculator provided by TI to calculate component values. I designed it to cut off output at >200mA of output current. Typical operating voltage is ~55-60V. This short circuit cut-off works fine in terms of cutting off the output in case of a downstream short circuit (or leakage current more than ~200-220mA. However, my expectation was that once the over-current/short circuit condition is removed, it should restart WITHOUT having to disconnect the load completely.
For example, I am testing my circuit with a Electronic Load configured to CC (constant current) mode. As I increase the current to >200mA, the LM5069 shuts off the output, as expected.
At this point, I start reducing the Electronic Load's Constant Current setting and expect the device to start up again (after the 7-8 seconds of delay) once the current draw is, let's say, set to 150mA. Instead it stays in fault mode. Even when I reduce the Electronic Load's CC setting down to 10mA it stays in fault mode. Only when I remove the load completely, the device restarts again. Is this how its supposed to work? For my use case, a load of <150mA is NOT a fault condition, and my expectation was that once the load falls below 150-200mA the device would turn on the mosfet again. Schematic is attached.
Pls advise what is the expected behaviour, and how I can get the behaviour I desire.
Best Regards,
Saad
