MAX6323/MAX6324 19-1838 Rev 6 1/11 P Supervisory Circuits with Windowed (Min/Max) Watchdog and Manual Reset General Description Features The MAX6323/MAX6324 microprocessor (P) supervi- Min/Max (Windowed) Watchdog, sory circuits monitor power supplies and P activity in 8 Factory-Trimmed Timing Options digital systems. A watchdog timer looks for activity out- Pulsed Open-Drain, Active-Low Watchdog Output side an expected window of operation. Six laser- trimmed reset thresholds are available with 2.5% Power-On Reset accuracy from +2.32V to +4.63V. Valid RESET output is Precision Monitoring of +2.5V, +3.0V, +3.3V, guaranteed down to V = +1.2V. CC and +5.0V Power Supplies The RESET output is either push-pull (MAX6323) or open-drain (MAX6324). RESET is asserted low when Open-Drain or Push-Pull RESET Outputs V falls below the reset threshold, or when the manual CC Low-Power Operation (23A typ) reset input (MR) is asserted low. RESET remains assert- Debounced Manual Reset Input ed for at least 100ms after V rises above the reset CC threshold and MR is deasserted. Guaranteed Reset Valid to V = +1.2V CC The watchdog pulse output (WDPO) utilizes an open- Ordering Information drain configuration. It can be triggered either by a fast timeout fault (watchdog input pulses are too close to TEMP PIN- RESET each other) or a slow timeout fault (no watchdog input PART RANGE PACKAGE OUTPUT pulse is observed within the timeout period). The MAX6323 UT -T -40C to +125C 6 SOT23 Push-Pull watchdog timeout is measured from the last falling edge of watchdog input (WDI) with a minimum pulse Ordering Information continued at end of data sheet. width of 300ns. WDPO is asserted for 1ms when a fault *These devices are factory trimmed to one of eight watchdog- is observed. Eight laser-trimmed timeout periods are timeout windows and one of six reset voltage thresholds. Insert available. the letter corresponding to the desired watchdog-timeout window (A, B, C, D, E, F, G, or H) into the blank following the number The MAX6323/MAX6324 are offered in a 6-pin SOT23 6323 or 6324 (see Watchdog Timeout table). Insert the two-digit package and operate over the extended temperature code (46, 44, 31, 29, 26, or 23) after the letters UT for the desired range (-40C to +125C). nominal reset threshold (see Reset Threshold Range table at end of data sheet). Applications /V denotes an automotive qualified part. Devices are available in both leaded and lead-free packaging. Automotive Specify lead-free by replacing -T with +T when ordering. Industrial Note: There are eight standard versions of each device available (see Standard Versions table). Sample stock is generally held on Medical standard versions only. Standard versions have an order incre- Embedded Control Systems ment requirement of 2500 pieces. Nonstandard versions have an order increment requirement of 10,000 pieces. Contact factory for availability of nonstandard versions. Pin Configuration Watchdog Timeout WATCHDOG TIMEOUT* TOP VIEW FAST SLOW SUFFIX MR16 RESET MAX UNITS MIN UNITS A 1.5 ms 10 B 15 ms 100 ms MAX6323 GND 2 5 WDPO MAX6324 C 15 ms 300 D 15 ms 10 s WDI34 V CC E 15 ms 60 F 23 ms 47 ms SOT23 G 39 ms 82 H 719 ms 1.3 s Typical Operating Circuit appears at end of data sheet. *See Figure 1 for operation. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.P Supervisory Circuits with Windowed (Min/Max) Watchdog and Manual Reset ABSOLUTE MAXIMUM RATINGS Terminal Voltage (with respect to GND) Operating Temperature Range .........................-40C to +125C V ..................................................................-0.3V to +6.0V Junction Temperature......................................................+150C CC MR, RESET (MAX6323), WDI................-0.3V to (V + 0.3V) Storage Temperature Range .............................-65C to +150C CC WDPO, RESET (MAX6324)..............................-0.3V to +6.0V Lead Temperature (soldering, 10s) .................................+300C Input Current, V , WDI, MR ..............................................20mA Soldering Temperature (reflow) CC Output Current, RESET, WDPO ..........................................20mA Lead(Pb)-Free............................................................+260C Rate of Rise, V ............................................................100V/s Containing Lead.........................................................+240C CC Continuous Power Dissipation (T = +70C) A 6-Pin SOT23 (derate 8.7mW/C above +70C)..........696mW 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 = full range, T = -40C to +125C, unless otherwise noted. Typical values are at V = 3V, T = +25C.) (Note 1) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Voltage Range V 1.2 5.5 V CC V = 2.5V or 3.3V 23 45 CC No load, RESET Supply Current I A CC deasserted V = 5.5V 27 57 CC MAX632 UT46 4.50 4.63 4.75 MAX632 UT44 4.25 4.38 4.50 MAX632 UT31 3.00 3.08 3.15 Reset Threshold Voltage V V TH MAX632 UT29 2.85 2.93 3.00 MAX632 UT26 2.55 2.63 2.70 MAX632 UT23 2.25 2.32 2.38 Reset Timeout Delay t RESET deasserted 100 180 280 ms RP 10mV/ms, V +100mV to V - 100mV 20 s V to RESET Delay CC TH TH I = 1.2mA, V = 2.25V (MAX632 UT23, SINK CC MAX632 UT26, MAX632 UT29, 0.4 MAX632 UT31) WDPO, RESET Output Voltage V V OL I = 3.2mA, V = 4.25V (MAX632 UT44, SINK CC 0.4 MAX632 UT46) I = 100A, V > 1.2V, RESET asserted 0.4 SINK CC I = 500A, V = 3.15V, RESET SOURCE CC 0.8 x V deasserted (MAX632 UT23, MAX632 UT26, CC RESET Output Voltage MAX632 UT29, MAX632 UT31) V V OH (MAX6323) I = 800A, V = 4.75V, RESET SOURCE CC V - 1.5 CC deasserted, (MAX632 UT44, MAX632 UT46) V = V = +5.5V, RESET, WDPO RESET WDPO WDPO, RESET Output Leakage I 1 A LKG deasserted 2 MAX6323/MAX6324