MAX1232 Microprocessor Monitor General Description Features The MAX1232 microprocessor (P) supervisory circuit Consumes 1/10th the Power of the DS1232 provides P housekeeping and power-supply supervision Precision Voltage MonitorAdjustable +4.5V or functions while consuming only 1/10th the power of the +4.75V DS1232. The MAX1232 enhances circuit reliability in P Power-OK/Reset Pulse Width250ms Min systems by monitoring the power supply, monitoring the No External Components software execution, and providing a debounced manual reset input. The MAX1232 is a plug-in upgrade of the Adjustable Watchdog Timer150ms, 600ms, or 1.2s Dallas DS1232. Debounced Manual Reset Input for External Override A reset pulse of at least 250ms duration is supplied on Available in 8-Pin PDIP/SO and 16-Pin Wide SO power-up, power-down, and low-voltage brownout con- Packages ditions (5% or 10% supply tolerances can be selected digitally). Also featured is a debounced manual reset Ordering Information input that forces the reset outputs to their active states for a minimum of 250ms. A digitally programmable watch- PART TEMP RANGE PIN-PACKAGE dog timer monitors software execution and can be pro- MAX1232C/D 0C to +70C Dice* grammed for timeout settings of 150ms, 600ms, or 1.2s. MAX1232CPA 0C to +70C 8 PDIP The MAX1232 requires no external components. MAX1232CSA 0C to +70C 8 SO Applications Ordering Information continued at end of data sheet. Computers *Contact factory for dice specifications. Controllers Note: Devices in PDIP and SO packages are available in both leaded(Pb) and lead(Pb)-free packaging. Specify lead(Pb)-free by Intelligent Instruments adding the + symbol at the end of the part number when order- Critical P Power Monitoring ing. Lead-free not available for CERDIP package. Pin Configurations Typical Operating Circuit TOP VIEW PB RST 1 8 V CC RST V TD 2 7 ST CC MAX1232 5%/10% TOLERANCE TOL 3 6 RST RESET TOL SELECT GENERATOR GND 4 5 RST REF RST DIP/SO MAX1232 PB RST DEBOUNCE N.C. 1 16 N.C. PB RST 2 15 V CC N.C. 3 14 N.C. MAX1232 TD 4 13 ST WATCHDOG TD WATCHDOG ST TIMEBASE N.C. 5 12 N.C. TIMER SELECT TOL 6 RST 11 N.C. 7 10 N.C. GND GND 8 9 RST WIDE SO 19-3899 Rev 2 9/14MAX1232 Microprocessor Monitor Absolute Maximum Ratings Voltage Range on Any Pin (with respect to GND) .....-1V to +7V Storage Temperature Range ............................ -65C to +160C Operating Temperature Range Lead Temperature (soldering, 10s) .................................+300C C Suffix ...............................................................0C to +70C E Suffix ........................................................... -40C to +85C M Suffix ......................................................... -55C to +125C 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. Recommended DC Operating Conditions (T = T to T , unless otherwise noted.) A MIN MAX PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Supply Voltage V 4.5 5.0 5.5 V CC ST and PBRST Input High Level V 2.0 V + 0.3 V IH CC (Note 1) ST and PBRST Input Low Level V -0.3 +0.8 V IL DC Electrical Characteristics (V = +4.5V to +5.5V, T = T to T , unless otherwise noted.) CC A MIN MAX PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS I -1.0 +1.0 A Input Leakage ST, TOL IL Output Current RST I V = 2.4V -1.0 -12 mA OH OH Output Current RST, RST I V = 0.4V 2.0 10 mA OL OL Operating Current (Note 2) I 50 200 A CC V 5% Trip Point (Note 3) V TOL = GND 4.50 4.62 4.74 V CC CCTP V 10% Trip Point (Note 3) V TOL = V 4.25 4.37 4.49 V CC CCTP CC Capacitance (Note 4) (T = +25C, unless otherwise noted.) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Capacitance ST, TOL C 5 pF IN Output Capacitance RST, RST C 7 pF OUT Maxim Integrated 2 www.maximintegrated.com