Tool/software:
We use TPS26601RHFR in an application we develop for a customer. We have tested it and abused it rather extensively, and it works just fine. (Reverse polarity, pulsed high currents, shorts etc.)
However a total of 4 (out of 26) e-fuses has failed when the customer flash the MCU that controls it (STM32). This has happened with just small currents flowing through the e-fuse. (4-30mA).
They all fail in the same way, internal mosfet between RTN and GND. (After fail RTN float at 48V, and the e-fuse draws approx 15mA).
We have 10k on all pins between MCU and tps2660 to protect the MCU.
Internal pullup on the MCU is used to pull FLT high. (No external resistor.)
Is there anyway the E-Fuse could fail because the unknown state of the pins during programing of the MCU?
