JAJSEW6B February 2018 – February 2024 UCC21222
PRODUCTION DATA
The input pins (INA, INB, and DIS) of the UCC21222 are based on a TTL and CMOS compatible input-threshold logic that is totally isolated from the VDD supply voltage of the output channels. The input pins are easy to drive with logic-level control signals (such as those from 3.3-V microcontrollers), since the UCC21222 has a typical high threshold (VINAH) of 1.8 V and a typical low threshold of 1 V, which vary little with temperature (see and Figure 5-13). A wide hysterisis (VINA_HYS) of 0.8 V makes for good noise immunity and stable operation. If any of the inputs are ever left open, internal pull-down resistors force the pin low. These resistors are typically 200 kΩ for INA/B and 50 kΩ for DIS (see Section 7.2). TI recommends grounding any unused inputs.
The amplitude of any signal applied to the inputs must never be at a voltage higher than VCCI.