GAT2 is the second gate drive output for the DC-DC converter. GAT2’s phase turns the second switch off when it transitions high, and on when it transitions low. This drives active-clamp PMOS devices per Figure 27, and driven flyback synchronous rectifiers per Figure 27. See the DT pin description for GATE to GAT2 timing. Connecting DT to VB disables GAT2 in a high-impedance condition. GAT2 is low when the converter is disabled.