DS1833Z-5+T&R Analog Devices

DS1833 5V EconoReset www.maxim-ic.com FEATURES PIN ASSIGNMENT Automatically restarts microprocessor after 1 power failure DALLAS DS1833 Maintains active-high reset for 350 ms after Econo Reset V returns to an in-tolerance condition CC Accurate 5%, 10% or 15% microprocessor 5V power supply monitoring 2 4 3 Reduces need for discrete components TOP VIEW SOT-23 PACKAGE Precision temperature-compensated voltage See Mech. Drawings Section reference and voltage sensor On Website 1 2 3 Low-cost TO-92 package or surface mount SOT-223 package 1 2 3 Internal 5k pull-up resistor Operating temperature of -40 C to +85 C BOTTOM VIEW TO-92 PACKAGE See Mech. Drawings Section On Website PIN DESCRIPTION PIN 1 Ground PIN 2 Reset PIN 3 V CC PIN 4 Ground (SOT-223 only) DESCRIPTION The DS1833 EconoReset uses a precision temperature compensated reference and comparator circuit to monitor the status of the power supply (V ). When an out-of-tolerance condition is detected, an internal CC power fail signal is generated which forces reset to the active (high) state. When V returns to an in- CC tolerance condition, the reset signal is kept in the active state for approximately 350 ms to allow the power supply and processor to stabilize. OPERATION - POWER MONITOR The DS1833 provides the functions of detecting out-of-tolerance power supply conditions and warning a processor-based system of impending power failure. When V is detected as out-of-tolerance, as CC defined by the tolerance of the part selected, the RST signal is asserted. On power-up, RST is kept active for approximately 350 ms after the power supply has reached the selected tolerance. This allows the power supply and microprocessor to stabilize before RST is released. 1 of 5 041002DS1833 BLOCK DIAGRAM Figure 1 APPLICATION EXAMPLE Figure 2 2 of 5