MAX697C/D Maxim Integrated, MAX697C/D Datasheet
MAX697C/D
Specifications of MAX697C/D
Related parts for MAX697C/D
MAX697C/D Summary of contents
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... Critical µP Power Monitoring Typical Operating Circuit appears at end of data sheet. Pin Configurations continued at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. ♦ Adjustable Low-Line Monitor and Power-Down Reset ♦ ...
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... Microprocessor Supervisory Circuits ABSOLUTE MAXIMUM RATINGS Terminal Voltage (with respect to GND) V .......................................................................-0. ....................................................................-0.3V to +6V BATT All Other Inputs (Note 1).......................-0. Input Current V CC............................................................................................. V BATT............................................................................................ GND .............................................................................................. Output Current V OUT ............................................................. All Other Outputs ...................................................................... Note 1: The input voltage limits on PFI and WDI may be exceeded providing the input current is limited to less than 10mA. ...
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... Microprocessor Supervisory Circuits ELECTRICAL CHARACTERISTICS (continued full operating range 2.8V BATT PARAMETER Reset Timeout Delay Figure 6, OSC SEL HIGH, V Long period, V Watchdog Timeout Period, Internal Oscillator Short period, V Long period Watchdog Timeout Period, External Clock Short period Minimum WDI Input Pulse Width ...
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... Microprocessor Supervisory Circuits (T = +25°C, unless otherwise noted _______________________________________________________________________________________ Typical Operating Characteristics MAX696 SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE 1.50 1.50 1.25 1.25 V MODE CC 1.00 1.00 0.75 0.75 0.50 0.50 BATTERY MODE T = 25°C 0.25 0. SUPPLY VOLTAGE (V) MAX697 SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE 250 200 150 ...
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... Microprocessor Supervisory Circuits PIN NAME MAX696 MAX697 1 — V BATT 2 — V OUT GND 5 — BATT ON LOW LINE OSC OSC SEL 9 9 PFI PFO WDI WDO 14 14 RESET RESET _______________________________________________________________________________________ FUNCTION Backup-Battery Input ...
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... Microprocessor Supervisory Circuits PIN NAME MAX696 MAX697 — 1 TEST CE OUT — — INPUT 0.1µF 3V BATTERY NO CONNECTION RESET Figure 1. MAX696 Typical Application Typical Applications A typical connection for the MAX696 is shown in Figure 1. CMOS RAM is powered from V OUT connected to V when power is present ...
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... Microprocessor Supervisory Circuits low for 50ms after LL rises above 1.3V. This prevents IN repeated toggling of RESET even if the V out and recovers with each power line cycle. The crystal oscillator normally used to generate the clock for microprocessors takes several milliseconds to start. Since most microprocessors need several clock cycles to reset, RESET must be held low until the microproces- sor clock oscillator has started ...
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... Microprocessor Supervisory Circuits The MAX697 is nearly identical to the MAX696. The MAX697 lacks the battery-backup feature does not have the BATT ON pins. This BATT OUT allows the MAX697 to consume less than 250 microam- peres, and it allows the inclusion of RAM write-protec- tion pins ...
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... Microprocessor Supervisory Circuits The MAX696 operates with battery voltages from 2.0V to 4.25V. The battery voltage should not be within 0. switchover may occur. High-value capaci- CC tors, either standard electrolytic or the farad-size dou- ble-layer capacitors, can also be used for short-term memory backup. The capacitor charging voltage should include a diode to limit the fully charged voltage to approximately 0 ...
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... Microprocessor Supervisory Circuits LL IN RESET OUTPUT LOW LINE OUTPUT (MAX697 (MAX697) CE OUT Figure 5. MAX697 Reset Timing CE Gating and RAM Write Protection The MAX697 uses two pins to control the CE or WRITE is > 1.3V, CE OUT is inputs of CMOS RAMs. When buffered replica of CE IN, with a 50ns propagation delay ...
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... Microprocessor Supervisory Circuits WATCHDOG INPUT V 2. 1.0V TRANSITION DETECTOR FOR EACH TRANSITION LOW LINE ( < 1.3V) IN Figure 6. Watchdog Timer Block Diagram becomes effective following the first transition of WDI after RESET has gone high. The watchdog timer is restarted at the end of reset, whether the reset was caused by lack of activity on WDI below 1 ...
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... Microprocessor Supervisory Circuits Applications Information Adding Hysteresis to the Power-Fail Since the power-fail comparator circuit is noninverting, hysteresis can be added by connecting a resistor between the PFO output and the PFI input as shown in Figure 7. When PFO is low, resistor R3 sinks current from the summing junction at the PFI pin. When PFO is high, the series combination of R3 and R4 source cur- rent into the PFI summing junction ...
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... Microprocessor Supervisory Circuits Table 1. MAX696 and MAX697 Reset Pulse Width and Watchdog Timeout Selections (Notes 1, 2) OSC SEL OSC IN (Note 3) Low External Clock Input 1024 clocks Low External Capacitor High/Floating Low High/Floating Floating Note 1: When the MAX696/MAX697 OSC SEL pin is low, OSC IN can be driven by an external clock signal external capacitor can be connected between OSC IN and GND ...
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... Microprocessor Supervisory Circuits -5V RESET Ordering Information PART TEMP RANGE MAX697C/D 0°C to +70°C MAX697CPE 0°C to +70°C MAX697CWE 0°C to +70°C MAX697EPE -40°C to +85°C MAX697EJE -40°C to +85°C MAX697EWE -40°C to +85°C MAX697MJE -55°C to +125°C Devices in PDIP and SO packages are available in both lead- ed and lead-free packaging ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2005 Maxim Integrated Products For the latest package outline information www ...