In order for the pre-charge circuitry to dampen the effect of hot-swap insertion of the TCA4311A into an active I²C bus, V_CC must be applied before the SCL and SDA pins make contact to the main I²C bus. This is essential when the TCA4311A is placed on the add-on card circuit board, as in Figure 12. Although the pre-charge circuitry exists on both the -IN and -OUT side, the example in Figure 12 shows SCLIN and SDAIN connecting to the main bus. The supply voltage to V_CC can be applied early by ensuring that the VCC and GND pin contacts are physically longer than the contacts for the SCLIN and SDAIN pins. If a voltage supervisor will also be used to control the voltage supply on the add-on card, additional delay will exist before the 1 V pre-charge voltage is present on the SCL and SDA pins.