MAX6841MAX6845 19-2625 Rev 2 12/05 Ultra-Low-Voltage P Reset Circuits and Voltage Detectors General Description Features Factory-Set Reset Threshold Voltages for The MAX6841MAX6845 microprocessor (P) supervi- Monitoring Supplies from 0.9V to 1.5V sory circuits monitor ultra-low-voltage power supplies in (MAX6841/MAX6842) P and digital systems. They provide excellent circuit reliability at low cost by eliminating external compo- Adjustable Threshold RESET IN nents and adjustments when used with +0.9V to +1.5V (MAX6843/MAX6844/MAX6845) systems. Factory-trimmed reset thresholds are avail- Low Power Consumption: 5.7A (typ) able for the MAX6841/MAX6842. The MAX6843/ 2.5% Reset Threshold Accuracy MAX6844/MAX6845 provide a RESET IN input, allowing Over Temperature the user to externally adjust the reset threshold. The Five Timeout Periods: 150s (Voltage Detector MAX6841MAX6845 family features a debounced man- Version), 1.5ms, 30ms, 210ms, and 1.68s ual reset input (MR). The reset comparator is designed to ignore fast transients on V . CC Available in Three Output Configurations Push-Pull RESET The MAX6841MAX6845 assert a reset signal whenev- Push-Pull RESET er the V supply voltage declines below a preset or CC Open-Drain RESET adjustable threshold or whenever manual reset (MR) is asserted. Reset remains asserted for a fixed timeout Guaranteed Reset Valid to V = 0.55V CC (Active Low) delay after V has risen above the reset threshold and CC when manual reset is deasserted. Five timeout periods Manual Reset Input are available for each part: 150s (voltage detector ver- Immune to Short V Transients CC sion), 1.5ms, 30ms, 210ms, and 1.68s (typ). Space-Saving 5-Pin SOT23 Package The MAX6841/MAX6843 have an active-low push-pull Ordering Information reset output. The MAX6841/MAX6842/MAX6844 have an active-high push-pull reset output, and the PART TEMP RANGE PIN-PACKAGE MAX6842/MAX6845 have an active-low open-drain MAX6841 UKD -T -40C to +85C5 SOT23-5 reset output. The active-low open-drain reset output requires a pullup resistor that can be connected to a MAX6842 UKD -T -40C to +85C5 SOT23-5 voltage from 0 to V . CC MAX6843UKD -T -40C to +85C5 SOT23-5 The low supply current (5.7A) and small package MAX6844UKD -T -40C to +85C5 SOT23-5 (SOT23-5) make the MAX6841MAX6845 ideal for use MAX6845UKD -T -40C to +85C5 SOT23-5 in portable equipment. Note: Insert desired suffix letter (from the Threshold Suffix Guide and the Active Timeout Period tables) into the blanks to com- plete the part number. For example, the MAX6842GUKD1 has a Applications reset threshold of 1.11V and a typical reset timeout period of 1.5ms. Sample stock is generally available on standard versions Computers only (see the Standard Versions table). Standard versions Controllers require a minimum order increment of 2.5k units. Nonstandard versions must be ordered in 10k-unit increments. Contact factory Intelligent Instruments for availability. All parts are offered in tape-and-reel only. Critical P and C Power Monitoring Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing -T with +T when ordering. Portable/Battery-Powered Equipment Telecom/Networking Equipment Pin Configurations Basestations TOP VIEW Servers/Workstations RESET RESET15V 15V CC CC (RESET) MAX6841 MAX6843 MAX6842 MAX6844 GND 2 GND 2 MAX6845 Selector Guide and Typical Operating Circuit appear at end RESET34 MR RESET IN34 MR of data sheet. SOT23-5 SOT23-5 ( ) ARE FOR 6844 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.Ultra-Low-Voltage P Reset Circuits and Voltage Detectors ABSOLUTE MAXIMUM RATINGS Terminal Voltage (with respect to GND) Continuous Power Dissipation (T = +70C) A V .......................................................................-0.3V to +6V 5-Pin SOT23 (derate 7.1mW/C above +70C)............571mW CC MR, RESET IN, RESET (open-drain).........................-0.3V to +6V Operating Temperature Range ...........................-40C to +85C Junction Temperature......................................................+150C Push-Pull RESET and RESET .....................-0.3V to (V + 0.3V) CC Storage Temperature Range .............................-65C to +150C Input Current (all pins) ........................................................20mA Lead Temperature (soldering, 10s) .................................+300C Output Current (RESET, RESET).........................................20mA 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 = +0.55V to +1.8V, T = -40C to +85C, unless otherwise noted. Typical values are at T = +25C.) (Note 1) CC A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS MAX6843/MAX6845 0.55 1.80 Supply Voltage Range V V CC MAX6841/MAX6842/MAX6844 (Note 2) 0.75 1.80 V = 0.9V, no load, reset not asserted 5.7 20 CC Supply Current I V = 1.5V, no load, reset not asserted 7.3 20 A CC CC V = 1.8V, no load, reset not asserted 8.1 20 CC I 1.350 1.388 1.425 H 1.275 1.313 1.350 Reset Threshold G 1.080 1.110 1.140 (V Falling) CC V V TH F 1.020 1.050 1.080 E 0.810 0.833 0.855 D, T = 0C to +85C 0.765 0.788 0.810 A RESET IN Threshold V MAX6843/MAX6844/MAX6845 (Note 3) 181.2 187.4 191.5 mV RSTIN RESET IN Leakage Current I -25 +25 nA RSTIN Reset Threshold Hysteresis V 0.75 %V HYS TH V falling, step signal from (V + 10%) CC TH V or RESET IN to Reset Delay 150 s CC to (V - 10%) within 1s TH D0 (voltage detector) 0.15 D1 1 1.5 2 Reset Active Timeout Period t D2 20 30 40 ms RP D3 140 210 280 D4 1120 1680 2240 V 0.3 V IL CC MR Input Voltage (Note 3) V V 0.7 V IH CC MR Minimum Input Pulse Width MR driven from V to 0 (Note 3) 1 s CC MR Glitch Rejection MR driven from V to 0 (Note 3) 150 ns CC MR to Reset Delay MR driven from V to 0 (Note 3) 500 ns CC MR Pullup Resistance to V 10 20 26 k CC 2 MAX6841MAX6845