19.4334Rev5995 1XI川 Low-Cost,uP Supervisory Circuits General Description Features The MAX705-MAX708/MAX8131 mi UMAX Package:Smallest 8-Pin so ory circuits um Guara teed RESET Valid at Vcc 1V ery functions in uP s po de vices sig 4.40V in MAX706/MAX708 The MAX705/MAX706/MAX813L provide four functions +200ms Reset Pulse Width 1owr-up.pr-down,and Debounced TTL/CMOS-Compatible Manual-Reset Input 2)An independent watchdog output that goes low if inut haso en dog Timer-1.sec Timeout 3)A 1.25V threshold detector for (MA707MAX7O8/A913L) +eaeewonitororPoaerfaorLowa8aieny 0 4AX707/MAX nual-reset input MAX706.except an aclive Ordering Information PART TEMP.RANGE PIN-PACKAGE MAX705CPA 0Ct0+70°C 8 Plastic DIP monitor levels are available:The MAX705CSA 0Ct0+70d 8 SO eAg58pwb when MAX705CUA 0Cto+70°C 8 HMAX MAX705C/D 0Ct0+70C Dice 02gar店aeaahteh8pnDPs0andwd Ordering Information continued at end of data sheet. Applications ocessing to MIL-STD-883. Computers Pin Configurations TOP VIEW Critical uP Power Monitoring 7 RESET (RESE GND 3 wo Typical Operating Circuit P阳4 ATED DC DIPISO MM DIP/SO MAXIM Maxim Integrated Products Call toll free 1-800-998-8800 for free samples or literature
MAX705–MAX708/MAX813L Low-Cost, µP Supervisory Circuits _ Maxim Integrated Products 1 TOP VIEW 1234 8765 WDO RESET (RESET) WDI PFI PFO GND VCC MR DIP/SO MAX705 MAX706 MAX813L 1234 8765 RESET RESET N.C. PFI PFO GND VCC MR DIP/SO MAX707 MAX708 ( ) ARE FOR MAX813L ONLY. Pin Configurations continued at end of data sheet. _Pin Configurations VCC PFI MR PFO WDO RESET UNREGULATED DC PUSHBUTTON SWITCH PFI I/O LINE INTERRUPT µP MAX705 MAX706 MAX813L MAX667 +5V DC LINEAR REGULATOR VCC RESET NMI _Typical Operating Circuit Call toll free 1-800-998-8800 for free samples or literature. 19-4334; Rev. 5; 9/95 _General Description The MAX705-MAX708/MAX813L microprocessor (µP) supervisory circuits reduce the complexity and number of components required to monitor power-supply and battery functions in µP systems. These devices significantly improve system reliability and accuracy compared to separate ICs or discrete components. The MAX705/MAX706/MAX813L provide four functions: 1) A reset output during power-up, power-down, and brownout conditions. 2) An independent watchdog output that goes low if the watchdog input has not been toggled within 1.6 seconds. 3) A 1.25V threshold detector for power-fail warning, low-battery detection, or for monitoring a power supply other than +5V. 4) An active-low manual-reset input. The MAX707/MAX708 are the same as the MAX705/ MAX706, except an active-high reset is substituted for the watchdog timer. The MAX813L is the same as the MAX705, except RESET is provided instead of RESET . Two supply-voltage monitor levels are available: The MAX705/MAX707/MAX813L generate a reset pulse when the supply voltage drops below 4.65V, while the MAX706/MAX708 generate a reset pulse below 4.40V. All four parts are available in 8-pin DIP, SO and µMAX packages. _Applications Computers Controllers Intelligent Instruments Automotive Systems Critical µP Power Monitoring _Features ♦ µMAX Package: Smallest 8-Pin SO ♦ Guaranteed RESET Valid at VCC = 1V ♦ Precision Supply-Voltage Monitor 4.65V in MAX705/MAX707/MAX813L 4.40V in MAX706/MAX708 ♦ 200ms Reset Pulse Width ♦ Debounced TTL/CMOS-Compatible Manual-Reset Input ♦ Independent Watchdog Timer—1.6sec Timeout (MAX705/MAX706) ♦ Active-High Reset Output (MAX707/MAX708/MAX813L) ♦ Voltage Monitor for Power-Fail or Low-Battery Warning _Ordering Information PART TEMP. RANGE PIN-PACKAGE MAX705CPA 8 Plastic DIP MAX705CSA 0°C to +70°C 8 SO MAX705C/D 0°C to +70°C Dice* Ordering Information continued at end of data sheet. * Dice are specified at TA = +25°C. **Contact factory for availability and processing to MIL-STD-883. 0°C to +70°C MAX705CUA 0°C to +70°C 8 µMAX
Low-Cost,uP Supervisory Circuits ABSOLUTE MAXIMUM RATINGS 网 ltage (with resp et to GND) 0 lewtcnnusNoe 20mA 0Cto+70℃ AX833L上 Output Current (all outputs) MAX70_MJA -55*℃10+125* 727mW 65℃o13688 Note 1:The input voltage limits on PFI and MR can be exceeded if the input current is less than 10mA. ELECTRICAL CHARACTERISTICS VCc 4./5V -4.5Vto 5.5V for MAX706/MAX708,TA-TMN to TAx.unless otherwise noted. PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS n MAX70 C 10 55 Operating voltage Range Vcc MAX813LC 1.1 -5.5 V MAX70_E/M,MAX813LE/M 12 5.5 35 upply Current A MAX707FMM MAX708F/M s00 MAX705,MAX707.MAX813L 4.50 4.65 4.75 Reset Threshold (Note 2) VRT V MAX706,MAX708 4.254.404.50 Reset Th shold Hysteresis (Note 2) Reset Pulse Width (Note 2) 15 200 2805 32m0 04 ESET Outout Voltage MAX70_C.Vcc 1V.IsINK -50JA 03 MAX70 E/M.VCC =1.2V.ISINK =100uA 0.3 MAX707,MAX708.ISOURCE 800JA VCC-1.5 .2m 0.4 RESET Output Voltage V.15 MAX813L ISOURCE 800UA ISINK-3.2mA 0.4 Watchdog Timeout Period MAX705,MAX706.MAX813L 1.001.602.25 sec WDI Pulse Width VIL -0.4V.VIH (VCC)(0.8) ns WDI Input Threshold MAX705.MAX706.MAXB13L. 0.8 MAX705.MAX706.MAX813L WDI=Vc 3.5 150 WDI Input Current MAX705.MAX706 MAX813L WDI OV -150-50 T Vcc-1.5 X707m706,a13L 0.4 MAXIM
MAX705–MAX708/MAX813L Low-Cost, µP Supervisory Circuits 2 _ Terminal Voltage (with respect to GND) VCC . -0.3V to 6.0V All Other Inputs (Note 1) . -0.3V to (VCC + 0.3V) Input Current VCC . 20mA GND . 20mA Output Current (all outputs) . 20mA Continuous Power Dissipation Plastic DIP (derate 9.09mW/°C above +70°C) . 727mW SO (derate 5.88mW/°C above +70°C) . 471mW µMAX (derate 4.10mW/°C above +70°C) . 330mW CERDIP (derate 8.00mW/°C above +70°C) . 640mW Operating Temperature Ranges MAX70_C_, MAX813LC_ . 0°C to +70°C MAX70_E_, MAX813LE_ . -40°C to +85°C MAX70_MJA . -55°C to +125°C Storage Temperature Range . -65°C to +160°C Lead Temperature (soldering, 10sec) . +300°C ELECTRICAL CHARACTERISTICS (VCC = 4.75V to 5.5V for MAX705/MAX707/MAX813L, VCC = 4.5V to 5.5V for MAX706/MAX708, TA = TMIN to TMAX, unless otherwise noted.) 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. PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Voltage Range VCC MAX70_C 1.0 5.5 MAX813LC 1.1 5.5 V MAX70_E/M, MAX813LE/M 1.2 5.5 Reset Threshold (Note 2) VRT MAX705, MAX707, MAX813L 4.50 4.65 4.75 MAX706, MAX708 4.25 4.40 4.50 40 mV Reset Pulse Width (Note 2) tRS 140 200 280 ms RESET Output Voltage ISOURCE = 800µA VCC - 1.5 V ABSOLUTE MAXIMUM RATINGS Note 1: The input voltage limits on PFI and MR can be exceeded if the input current is less than 10mA. Reset Threshold Hysteresis (Note 2) ISINK = 3.2mA 0.4 0.3 0.3 RESET Output Voltage MAX707, MAX708, ISOURCE = 800µA V MAX707, MAX708, ISINK = 1.2mA 0.4 0.8 0.9 MAX813L VCC - 1.5 0.4 Watchdog Timeout Period tWD MAX705, MAX706, MAX813L 1.00 1.60 2.25 sec WDI Pulse Width tWP VIL = 0.4V, VIH = (VCC) (0.8) 50 ns WDI Input Threshold 0.8 V 3.5 MAX70_C, VCC = 1V, ISINK = 50µA MAX70_E/M, VCC = 1.2V, ISINK = 100µA MAX813LC, ISOURCE = 4µA, VCC = 1.1V MAX813LE/M, ISOURCE = 4µA, VCC = 1.2V ISOURCE = 800µA ISINK = 3.2mA Low High WDI Input Current MAX705, MAX706, MAX813L, WDI = VCC 50 150 µA MAX705, MAX706, MAX813L, WDI = 0V -150 -50 WDO Output Voltage VCC - 1.5 V 0.4 MAX705, MAX706, MAX813L, VCC = 5V MAX705, MAX706, MAX813L, ISOURCE = 800µA MAX705, MAX706, MAX813L, ISINK = 1.2mA V VCC - 1.5 MAX707C, MAX708C 50 350 MAX707E/M, MAX708E/M 50 500 Supply Current ISUPPLY MAX705C, MAX706C, MAX813LC 150 350 µA MAX705E/M, MAX706E/M, MAX813LE/M 150 500
Low-Cost,uP Supervisory Circuits ELECTRICAL CHARACTERISTICS(continued) (Vcc 4.75V to 5.5V for MAX70 707/MAXB13L.Vcc-4.5Vto 5.5Vfor MAX706/MAX708.TA-TN o TMAx unless otherwise noted.) PARAMETER SYMBOL CONDITIONS TYP MAX UNITS MR Pull-Up Cu urrent 250 600μA MR Pulse Width tMR 150 ns M Input Threshold 0.8 MR to Reset Out Delay (Note 2 250 ns PFI Input Threshold VCC =5V 120 25 130 PFI Input Current 25.00 0.01 25.00nA PFO Output Voltage ISOURCE -800uA cc.1.5 IsINK-3.2mA 0.4 Note 2:Applies to both RESET in the MAX705-MAX708 and RESET in the MAX707/MAX708/MAX813L. MAX705-MAX708/MAX813L MAXIM
MAX705–MAX708/MAX813L Low-Cost, µP Supervisory Circuits _ 3 ELECTRICAL CHARACTERISTICS (continued) (VCC = 4.75V to 5.5V for MAX705/MAX707/MAX813L, VCC = 4.5V to 5.5V for MAX706/MAX708, TA = TMIN to TMAX, unless otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 0.8 V 2.0 MR Pull-Up Current MR = 0V 100 250 600 µA MR Pulse Width tMR 150 ns Low High MR Input Threshold MR to Reset Out Delay (Note 2) tMD 250 ns PFI Input Threshold VCC = 5V 1.20 1.25 1.30 V PFI Input Current -25.00 0.01 25.00 nA PFO Output Voltage ISOURCE = 800µA VCC - 1.5 V ISINK = 3.2mA 0.4 Note 2: Applies to both RESET in the MAX705-MAX708 and RESET in the MAX707/MAX708/MAX813L
Low-Cost,uP Supervisory Circuits Typical Operating Characteristics BESET RESPONSE TIME 乏2k GND 500m 400e/ POWER-FAIL COMPARATOR RESET.RESET DE-ASSERTION 1 RESET RESPONS E TIME MAXIM
MAX705–MAX708/MAX813L Low-Cost, µP Supervisory Circuits 4 _ _Typical Operating Characteristics MAX707/MAX708/MAX813L RESET OUTPUT VOLTAGE vs. SUPPLY VOLTAGE 500ms/div VCC 0V RESET 0V +5V 1V/div +5V 1V/div T A = +25°C GND RESET VCC 330pF 10k MAX813L RESET RESPONSE TIME 2µs/div +5V VCC 0V 0V +4V +4V GND RESET VCC 10k 330pF MAX705/MAX707 RESET OUTPUT VOLTAGE vs. SUPPLY VOLTAGE 500ms/div VCC 0V RESET 0V +5V 1V/div +5V 1V/div VCC GND RESET VCC 2k RESET 330pF T A = +25°C MAX705/MAX707 RESET RESPONSE TIME 2µs/div VCC +5V RESET +5V +4V 1V/div 0V T A = +25°C VCC GND RESET VCC 10k RESET 30pF POWER-FAIL COMPARATOR DE-ASSERTION RESPONSE TIME 400ns/div PFI +1.20V PFO 0V +3V +1.30V VCC = +5V TA = +25°C +5V PFO 30pF 1k +1.25V PFI POWER-FAIL COMPARATOR ASSERTION RESPONSE TIME 400ns/div PFI +1.30V PFO +5V 0V +1.20V +5V 1V/div 50mV/div PFO 30pF 1k +1.25V PFI VCC = +5V TA = +25°C MAX707 RESET, RESET ASSERTION 400ns/div 0V +5V RESET RESET 1V/div VCC = VRT TA = +25°C +5V 0V VCC GND RESET 10k 330pF RESET 10k 330pF MAX707 RESET, RESET DE-ASSERTION 400ns/div 0V +5V RESET RESET 2V/div VCC = VRT TA = +25°C +5V 0V VCC GND RESET RESET 10k 330pF 10k 330pF
Low-Cost,uP Supervisory Circuits _Pin Description 3 MAX705/MAX706 MAX813 NAME FUNCTION IP/SO P/SC 3 R nal 250uA pull-up current.It can be driven from a TTL 2 2 2 4 Vcc +5V Supply Input 3 3 5 3 5 GND OV Ground Reference for all signals Power-Fail Voltage Monitor Input.When PFI is less 6 PFI than 1.25V,PFO goes low.Connect PFI to GND or MAX708/ Vcc when not used PFO WDO g s low (Figure 1).Floating WDI or connect- 8 6 WDI 6 N.C. No Connect Active-Low Reset Output pulses low for200ms when threshold (4.65Vin the MAX70 and 4 40v in the 7 1 7 1 RESET connected Watchdog Output pulls low when the internal watch- not go 8 2 2 WDO er Vec is old,WDO goes high with no delay. wcretghReetOibuti5stener5eotREsET 1 RESET MAXIM
MAX705–MAX708/MAX813L Low-Cost, µP Supervisory Circuits _ 5 _Pin Description Watchdog Output pulls low when the internal watchdog timer finishes its 1.6sec count and does not go high again until the watchdog is cleared. WDO also goes low during low-line conditions. Whenever VCC is below the reset threshold, WDO stays low; however, unlike RESET, WDO does not have a minimum pulse width. As soon as VCC rises above the reset threshold, WDO goes high with no delay. Active-High Reset Output is the inverse of RESET . Whenever RESET is high, RESET is low, and vice versa (Figure 2). The MAX813L has a RESET output only. Active-Low Reset Output pulses low for 200ms when triggered, and stays low whenever VCC is below the reset threshold (4.65V in the MAX705 and 4.40V in the MAX706). It remains low for 200ms after VCC rises above the reset threshold or MR goes from low to high (Figure 3). A watchdog timeout will not trigger RESET unless WDO is connected to MR . Watchdog Input. If WDI remains high or low for 1.6sec, the internal watchdog timer runs out and WDO goes low (Figure 1). Floating WDI or connecting WDI to a high-impedance three-state buffer disables the watchdog feature. The internal watchdog timer clears whenever reset is asserted, WDI is threestated, or WDI sees a rising or falling edge. Power-Fail Output goes low and sinks current when PFI is less than 1.25V; otherwise PFO stays high. Power-Fail Voltage Monitor Input. When PFI is less than 1.25V, PFO goes low. Connect PFI to GND or VCC when not used. MAX705/MAX706 FUNCTION - 8 7 RESET 8 - 8 WDO 7 7 - RESET - 6 - N.C. No Connect 6 - 6 WDI 5 5 5 PFO 4 4 4 PFI 3 3 3 GND 0V Ground Reference for all signals 2 2 2 VCC +5V Supply Input NAME DIP/SO DIP/SO DIP/SO MAX707/MAX708 PIN -21-87654 µMAX 2-1-7654 µMAX 12-87654 µMAX MAX813L Manual-Reset Input triggers a reset pulse when pulled below 0.8V. This active-low input has an internal 250µA pull-up current. It can be driven from a TTL or CMOS logic line as well as shorted to ground with a switch. 1 3 1 3 1 3 MR