Maxim Integrated MAX6443-MAX6452 Microprocessor Reset CircuitsMaxim Integrated
MAX6443-MAX6452 low-current microprocessor reset circuits feature single or dual manual reset inputs with an extended set up period. Because of the extended setup period, short switch closures (nuisance resets) are ignored. On all Maxim Integrated MAX644x and MAX645x microprocessor reset circuits, the reset output asserts when any of the monitored supply voltages drops below its specified threshold. The rest output remains asserted for the reset time period (210ms typ.) after all monitored supplies exceed their reset thresholds. The reset output is one-shot pulse asserted for the reset timeout period (140ms min.) when selected manual reset inputs are held low for an extended setup time period. These Maxim Integrated devices ignore manual reset transitions of less than the extended setup timeout period. The MAX6443-MAX6448 are single fixed-voltage microprocessor supervisors. The MAX6443 / MAX6444 have a single extended manual reset input. The MAX6445 and MAX6446 have two extended manual reset inputs. The MAX6447 / MAX6448 have one extended and one immediate manual reset input. MAX6449-MAX6452 devices have one fixed-threshold microprocessor supervisor and one adjustable-threshold microprocessor supervisor. The MAX6449 and MAX6450 have two delayed manual reset inputs. MAX6451 and MAX6452 devices have one delayed and one immediate manual reset input. Maxim Integrated MAX644x / MAX645x devices are ideal for use in set-top boxes, consumer electronics, DVD players, and more.FEATURES· Single or Dual-Supply Voltage Monitors
· Precision Factory-Set Reset Thresholds from 1.6V to 4.6V
· Adjustable Threshold to Monitor Voltages Down to 0.63V (MAX6449–MAX6452)
· Single or Dual Manual Reset Inputs with Extended Setup Period
· Optional Short Setup Time Manual Reset Input (MAX6447/MAX6448 and MAX6451/MAX6452)
· Immune to Short Voltage Transients
· Low 6μA Supply Current
· Guaranteed Valid Reset Down to VCC = 1.0V
· Active-Low RESET (Push-Pull or Open-Drain) Outputs
· 140ms (min) Reset Timeout Period
· Small SOT143 and SOT23 Packages
TYPICAL OPERATING CIRCUIT