VCC 7
Device supply: External bias supply input. Under Voltage Lock Out (UVLO) disables the controller until VCC exceeds a turn-on threshold of 10.5 V. Operation continues until VCC falls below the turn-off (UVLO) threshold of 9.5 V. A ceramic by-pass capacitor of 0.1 µ F minimum value should be connected from VCC to GND as close to the device as possible for high frequency filtering of the VCC voltage.
VINS 4 I
Input ac voltage sense: Input Brown Out Protection (IBOP) detects when the system ac-input voltage is above a user-defined normal operating level, or below a user-defined “ brown-out ” level. A filtered resistor-divider network connects from this pin to the rectified-mains node. At startup the controller is disabled until the VINS voltage exceeds a threshold of 1.5 V, initiating a soft-start. The controller is also disabled if VINS drops below the brown-out threshold of 0.8 V. Operation will not resume until both VINS and VSENSE voltages exceed their enable thresholds, initiating another soft-start.
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