MAX6821MAX6825 19-1868 Rev 2 12/05 Low-Voltage SOT23 P Supervisors with Manual Reset and Watchdog Timer General Description Features The MAX6821MAX6825 are low-voltage microprocessor Monitors +1.8V, +2.5V, +3.0V, +3.3V, +5.0V (P) supervisory circuits that combine voltage monitor- Supplies ing, watchdog timer, and manual reset input functions in 140ms (min) Reset Timeout Delay a 5-pin SOT23 package. Microprocessor supervisory cir- 1.6s Watchdog Timeout Period cuits significantly improve system reliability and accura- (MAX6821/MAX6822/MAX6823/MAX6824) cy compared to separate ICs or discrete components. Manual Reset Input These devices assert a reset signal whenever the moni- tored voltage drops below its preset threshold, keeping it (MAX6821/MAX6822/MAX6823/MAX6825) asserted for a minimum timeout period after V rises CC Three Reset Output Options above the threshold. In addition, a watchdog timer moni- Push-Pull RESET tors against code execution errors. A debounced manual Push-Pull RESET reset is also available. The MAX6821MAX6825 monitor Open-Drain RESET voltages from +1.8V to +5.0V. These outputs are guaran- Guaranteed Reset Valid to V = +1.0V CC teed to be in the correct state for V down to +1.0V. CC Immune to Short Negative V Transients CC Nine preprogrammed reset threshold voltages are No External Components available (see the Threshold Suffix Guide). The Small 5-Pin SOT23 Packages MAX6821, MAX6822, and MAX6823 all have a manual reset input and a watchdog timer. The MAX6821 has Ordering Information push-pull RESET, the MAX6822 has open-drain RESET, and the MAX6823 has push-pull RESET. The MAX6824 PART* TEMP RANGE PIN-PACKAGE has a watchdog timer and both push-pull RESET and MAX6821 UK-T -40C to +125C 5 SOT23-5 push-pull RESET. The MAX6825 has a manual reset MAX6822 UK-T -40 C to +125C 5 SOT23-5 input and both push-pull RESET and push-pull RESET. MAX6823 UK-T -40C to +125C 5 SOT23-5 The Selector Guide explains the functions offered in this series of parts. MAX6824 UK-T -40C to +125C 5 SOT23-5 MAX6825 UK-T -40 C to +125C 5 SOT23-5 Applications *Insert the desired suffix letter (from the table below) into the blank Set-Top Boxes Automotive Systems to complete the part number Computers and Critical P Monitoring Devices are available in both leaded and lead-free packaging. Controllers Specify lead-free by replacing -T with +T when ordering. Portable/Battery- Embedded Controllers Powered Equipment Threshold Suffix Guide Intelligent Instruments RESET SUFFIX THRESHOLD (V) Pin Configurations L 4.63 TOP VIEW M 4.38 T 3.08 RESET(RESET)15 V CC S 2.93 R 2.63 MAX6821 GND 2 MAX6822 Z 2.32 MAX6823 Y 2.19 MR34 WDI W 1.67 V 1.58 SOT23-5 Note: Bold indicates standard versions. Samples are typically (RESET) MAX6821 ONLY available for standard versions only. All parts require a 2.5k Pin Configurations continued at end of data sheet. minimum order increment. Contact factory for availability. Typical Operating Circuit appears at end of data sheet. Selector Guide appears at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Low-Voltage SOT23 P Supervisors with Manual Reset and Watchdog Timer ABSOLUTE MAXIMUM RATINGS V to GND...........................................................-0.3V to +6.0V Operating Temperature Range .........................-40C to +125C CC Junction Temperature......................................................+150C Open-Drain RESET................................................-0.3V to +6.0V Storage Temperature Range .............................-65C to +150C Push-Pull RESET, RESET, MR, WDI ...........-0.3V to (V + 0.3V) CC Lead Temperature (soldering, 10s) .................................+300C Input Current (V ).............................................................20mA CC Output Current (RESET, RESET).........................................20mA Continuous Power Dissipation (T = +70C) A 5-Pin SOT23 (derate 7.1mW/C above +70C)............571mW Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = +4.5V to +5.5V for MAX682 L/M, V = +2.7V to +3.6V for MAX682 T/S/R, V = +2.1V to +2.75V for MAX682 Z/Y, V = CC CC CC CC +1.53V to +2.0V for MAX682 W/V, T = -40C to +125C, unless otherwise specified. Typical values are at T = +25C.) (Note 1) A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS T = 0C to +85C 1.0 5.5 A Operating Voltage Range V V CC T = -40C to +125C 1.2 5.5 A T = -40C to +85C 10 20 A V = +5.5V, no load CC T = -40C to +125C 30 A T = -40C to +85C 716 V Supply Current A CC I V = +3.6V, no load A CC CC (MR and WDI Unconnected) T = -40C to +125C 25 A T = -40C to +85C 512 V = +3.6V, no load A CC (MAX6825 only) T = -40C to +125C 20 A T = -40C to +85C 4.50 4.63 4.75 A MAX682 L T = -40C to +125C 4.47 4.63 4.78 A T = -40C to +85C 4.25 4.38 4.50 A MAX682 M T = -40C to +125C 4.22 4.38 4.53 A T = -40C to +85C 3.00 3.08 3.15 A MAX682 T T = -40C to +125C 2.97 3.08 3.17 A T = -40C to +85C 2.85 2.93 3.00 A MAX682 S T = -40C to +125C 2.83 2.93 3.02 A V Reset Threshold CC V T = -40C to +85C 2.55 2.63 2.70 V TH A (V Falling) CC MAX682 R T = -40C to +125C 2.53 2.63 2.72 A T = -40C to +85C 2.25 2.32 2.38 A MAX682 Z T = -40C to +125C 2.24 2.32 2.40 A T = -40C to +85C 2.12 2.19 2.25 A MAX682 Y T = -40C to +125C 2.11 2.19 2.27 A T = -40C to +85C 1.62 1.67 1.71 A MAX682 W T = -40C to +125C 1.61 1.67 1.72 A MAX682 V T = -40C to +85C 1.52 1.58 1.62 A Reset Threshold Temperature 60 p p m/C Coefficient Reset Threshold Hysteresis 2 V mV TH V to Reset Output Delay t V = V to (V - 100mV) 20 s CC RD CC TH TH 2 MAX6821MAX6825