ZC706 supports a range of VADJ voltages, including 1.8V.
However, when the VADJ is modified from the default 2.5V to 1.8V, the fan onboard the ZC706 does not continue to spin.
The fan can recover if manually started (with a push) but spins with a slower speed (compared to when VADJ is set to 2.5V).
Why is this?
The fan spins with manual assistance because the FET acts like a current limiting resistor when the VGS is lower than 2V - the fan requires a greater start up current initially, and once spinning it requires less current to continue spinning.
The fan spins more slowly as the FET resistance is also dropping the voltage.
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