The A and B drivers may be combined into a single driver by connecting the INA/INB inputs together as close to the IC as possible, and the OUTA/OUTB outputs ties together if the external gate drive resistor is not used. In some cases where the external gate drive resistor is used, Ti recommends that the resistor can be equally split in OUTA and OUTB respectively to reduce the parasitic inductance induce unbalance between two channels, as show in Figure 8.
Important consideration about paralleling two channels for UCCx7323/4 include: 1) INA and INB should be shorted in PCB layout as close to the device as possible, as well as for OUTA and OUTB, in which condition PCB layout parasitic mismatching between two channels could be minimized. 2) INA/B input slope signal should be fast enough to avoid mismatched VIN_H/VIN_L, td1/td2 between channel-A and channel-B. TI recommends having input signal slope faster than 20 V/us.