TPS3820-33,pdf(Processor Super

The TPS382x family of supervisors provides circuit initialization and timing supervision, primarily for DSP and processor-based systems.

During power-on, RESET is asserted when supply voltage V_DD becomes higher than 1.1 V. Thereafter, the supply voltage supervisor monitors V_DD and keeps RESET active as long as V_DD remains below the threshold voltage V_IT– . An internal timer delays the return of the output to the inactive state (high) to ensure proper system reset. The delay time, t_d, starts after V_DD has risen above the threshold voltage V_IT–. When the supply voltage drops below the threshold voltage V_IT–, the output becomes active (low) again. No external components are required. All the devices of this family have a fixed-sense threshold voltage V_IT– set by an internal voltage divider.