DS1834A Datasheet | Dallas Semiconductor

.. DS1834/A/D Dual Econo Reset with Pushbutton .dalsemi. Features 5V power-on reset 3.3V power-on reset Internal power is drawn from higher of either the 5VIN input or the 3.3VIN input Excellent for systems designed to operate with dual power supplies Asserts resets during power transients Pushbutton reset input for system override Maintains reset for 350 ms after VCC returns to an in-tolerance condition Reduces need for discrete ponents Precision temperature-pensated voltage reference and voltage sensor 8-pin DIP, 8-pin SOIC, and 8-pin µ-SOP available CMOS output for low current operation on the DS1834 and DS1834D Operating temperature of -40°C to +85°C PIN ASSIGNMENT 5VIN 5V RST 5V TOL GND 1 2 3 4 8 7 6 5 3.3VIN 3.3V RST 3.3V TOL PBRST DS1834 8-Pin DIP (300-mil) 5VIN 5V RST 5V TOL GND 1 2 3 4 8 7 6 5 3.3VIN 3.3V RST 3.3V TOL PBRST DS1834 8-Pin SOIC (150-mil) 5VIN 5V RST (- RST) 5V TOL GND 1 2 3 4 8 7 6 5 3.3VIN 3.3V RST (- RST) 3.3V TOL PBRST DS1834 8-Pin µ-SOP (118-mil) PIN DESCRIPTION 5VIN 5V RST (- RST) 5V TOL GND - 5V Power Supply Input - 5V Reset Output - Selects 5V Input Tolerance - Ground PBRST - Pushbutton Reset 3.3V TOL - Selects 3.3V Input Tolerance 3.3V RST (- RST) - 3.3V Reset Output 3.3VIN - 3.3V Power Supply Input - DS1834D Active High Reset DESCRIPTION The DS1834 Dual Econo Resets monitors three vital system conditions: 5-volt supply, 3.3-volt supply, and an external override. First a precision temperature reference and parator circuit monitor the status of the 5-volt supply and the 3.3-volt supply. When an out-of-tolerance condition is detected, an internal power-fail signal is generated which forces the reset of the affected supply to an active state. Lastly, the DS1834 supports an external reset via an internally debounced pushbutton input. When the pushbutton is pulled low both resets will be asserted for approximately 350 ms after the pushbutton is released. 1 of 7 071700 DS1834/A/D OPERATION Power Monitor...