7.3.1 4-Level Input Pins and Thresholds

The 4-level input configuration pins use a resistor divider to provide four logic states for each control pin. There is an internal 30-kΩ pullup and a 60-kΩ pulldown connected to the control pin that sets the default voltage at 2/3 × VIN. These resistors, together with the external resistor, combine to achieve the desired voltage level. By using the 1-kΩ pulldown, 20-kΩ pulldown, no connect, and 1-kΩ pullup, the optimal voltage levels for each of the four input states are achieved as shown in Table 1.

Typical 4-Level Input Thresholds:

• Internal Threshold between L and R = 0.2 × VIN
• Internal Threshold between R and F = 0.5 × VIN
• Internal Threshold between F and H = 0.8 × VIN