MAX6340/MAX6421MAX6426 19-2440 Rev 4 12/05 Low-Power, SC70/SOT P Reset Circuits with Capacitor-Adjustable Reset Timeout Delay General Description Features The MAX6340/MAX6421MAX6426 low-power micro- Monitor System Voltages from 1.6V to 5V processor supervisor circuits monitor system voltages Capacitor-Adjustable Reset Timeout Period from 1.6V to 5V. These devices perform a single function: they assert a reset signal whenever the V supply volt- CC Low Quiescent Current (1.6A typ) age falls below its reset threshold. The reset output Three RESET Output Options remains asserted for the reset timeout period after V CC rises above the reset threshold. The reset timeout is exter- Push-Pull RESET nally set by a capacitor to provide more flexibility. Push-Pull RESET Open-Drain RESET The MAX6421/MAX6424 have an active-low, push- pull reset output. The MAX6422 has an active-high, Guaranteed Reset Valid to V = 1V CC push-pull reset output and the MAX6340/MAX6423/ Immune to Short V Transients CC MAX6425/MAX6426 have an active-low, open-drain reset output. The MAX6421/MAX6422/MAX6423 are Small 4-Pin SC70, 4-Pin SOT143, and 5-Pin SOT23 offered in 4-pin SC70 or SOT143 packages. The Packages MAX6340/MAX6424/MAX6425/MAX6426 are available MAX6340 Pin Compatible with LP3470 in 5-pin SOT23-5 packages. MAX6424/MAX6425 Pin Compatible with NCP300NCP303, MC33464/MC33465, S807/S808/S809, and RN5VD Applications MAX6426 Pin Compatible with PST92XX Portable Equipment Battery-Powered Computers/Controllers Ordering Information Automotive PART TEMP RANGE PIN-PACKAGE Medical Equipment MAX6340UK -T -40C to +125C 5 SOT23-5 Intelligent Instruments MAX6421XS -T -40C to +125C 4 SC70-4 Embedded Controllers MAX6421US -T -40C to +125C 4 SOT143-4 Critical P Monitoring MAX6422XS -T -40C to +125C 4 SC70-4 Set-Top Boxes MAX6422US -T -40C to +125C 4 SOT143-4 MAX6423XS -T -40C to +125C 4 SC70-4 Computers MAX6423US -T -40C to +125C 4 SOT143-4 MAX6424UK -T -40C to +125C 5 SOT23-5 Typical Operating Circuit appears at end of data sheet. MAX6425UK -T -40C to +125C 5 SOT23-5 Pin Configurations MAX6426UK -T -40C to +125C 5 SOT23-5 Note: The MAX6340/MAX6421MAX6426 are available with fac- TOP VIEW tory-trimmed reset thresholds from 1.575V to 5.0V in approxi- mately 0.1V increments. Insert the desired nominal reset threshold suffix (from Table 1) into the blanks. There are 50 stan- V CC 14 RESET dard versions with a required order increment of 2500 pieces. (RESET) MAX6421X MAX6422X Sample stock is generally held on standard versions only (see MAX6423X Standard Versions Table). Required order increment is 10,000 3 SRT GND 2 pieces for nonstandard versions. Contact factory for availability. All devices are available in tape-and-reel only. SC70 Devices are available in both leaded and lead-free packaging. Specify lead-free by replacing- with+ when ordering. ( ) ARE FOR THE MAX6422 Pin Configurations continued 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-Power, SC70/SOT P Reset Circuits with Capacitor-Adjustable Reset Timeout Delay ABSOLUTE MAXIMUM RATINGS All Voltages Referenced to GND Continuous Power Dissipation (T = +70C) A V ........................................................................-0.3V to +6.0V 4-Pin SC70 (derate 3.1mW/C above +70C)..............245mW CC SRT, RESET, RESET (push-pull).................-0.3V to (V + 0.3V) 4-Pin SOT143 (derate 4mW/C above +70C).............320mW CC 5-Pin SOT23 (derate 7.1mW/C above +70C)............571mW RESET (open drain)...............................................-0.3V to +6.0V Operating Temperature Range .........................-40C to +125C Input Current (all pins)......................................................20mA Storage Temperature Range .............................-65C to +150C Output Current (RESET, RESET) ......................................20mA Junction Temperature......................................................+150C Lead Temperature (soldering, 10s) .................................+300C 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 = 1V to 5.5V, T = T to T , unless otherwise specified. Typical values are at V = 5V and T = +25C.) (Note 1) CC A MIN MAX CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage Range V 1.0 5.5 V CC V 5.0V 2.5 4.2 CC Supply Current I V 3.3V 1.9 3.4 A CC CC V 2.0V 1.6 2.5 CC T = +25C V - 1.5% V + 1.5% A TH TH V Reset Threshold Accuracy V V CC TH T = -40C to +125C V - 2.5% V + 2.5% A TH TH Hysteresis V 4 x V mV HYST TH V to Reset Delay t V falling at 1mV/s 80 s CC RD CC C = 1500pF 3.00 4.375 5.75 SRT Reset Timeout Period t ms RP C = 0 0.275 SRT V Ramp Current I V = 0 to 0.65V V = 1.6V to 5V 240 nA SRT RAMP SRT CC V Ramp Threshold V V = 1.6V to 5V (V rising) 0.65 V SRT TH-RAMP CC RAMP RAMP Threshold Hysteresis V falling threshold 33 mV RAMP V 1.0V, I = 50A 0.3 CC SINK RESET Output Voltage Low V V 2.7V, I = 1.2mA 0.3 V OL CC SINK V 4.5V, I = 3.2mA 0.4 CC SINK V 1.8V, I = 200A 0.8 x V CC SOURCE CC RESET Output Voltage High, V V 2.25V, I = 500A 0.8 x V V OH CC SOURCE CC Push-Pull V 4.5V, I = 800A 0.8 x V CC SOURCE CC RESET Output Leakage Current, I V > V , reset not asserted 1.0 A LKG CC TH Open-Drain V 1.0V, I = 1A 0.8 x V CC SOURCE CC V 1.8V, I = 150A 0.8 x V CC SOURCE CC RESET Output Voltage High V V OH V 2.7V, I = 500A 0.8 x V CC SOURCE CC V 4.5V, I = 800A 0.8 x V CC SOURCE CC V 1.8V, I = 500A 0.3 CC SINK RESET Output Voltage Low V V OL V 2.7V, I = 1.2mA 0.3 CC SINK V 4.5V, I = 3.2mA 0.4 CC SINK Note 1: Devices production tested at +25C. Overtemperature limits are guaranteed by design. 2 MAX6340/MAX6421MAX6426