ADM697 Analog Devices, ADM697 Datasheet
ADM697
Specifications of ADM697
Available stocks
Related parts for ADM697
ADM697 Summary of contents
Page 1
... These functions include P reset, backup-battery switchover, watchdog timer, CMOS RAM write protection, and power failure warning. The ADM696/ADM697 are available in 16-pin DIP and small outline packages and provide the following functions: 1. Power-On Reset output during power-up, power-down and brownout conditions ...
Page 2
... WDI Input Current POWER FAIL DETECTOR PFI Input Threshold PFI–LL Threshold Difference IN PFI Input Current LL Input Current IN PFO Output Voltage PFO Short Circuit Source Current CHIP ENABLE GATING (ADM697) CE Threshold IN CE Pullup Current IN CE Output Voltage OUT CE Propagation Delay OSCILLATOR ...
Page 3
... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the ADM696/ADM697 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
Page 4
... ADM696/ADM697 Pin No. Mnemonic ADM696 ADM697 — BATT V 2 — OUT GND 4 5 RESET 15 15 WDI 11 11 PFI 9 9 PFO — — 12 OUT BATT ON 5 — LOW LINE 6 6 RESET 16 16 OSC SEL 8 8 OSC WDO ...
Page 5
... An output line on the processor is used to toggle the Watchdog Input (WDI) line. If this line is not toggled within the selected timeout period, a RESET pulse is generated. The ADM696/ADM697 may be configured for either a fixed should be BATT “short” 100 “long” 1.6 second timeout period or for an ...
Page 6
... ADM696/ADM697 Table I. ADM696, ADM697 Reset Pulse Width and Watchdog Timeout Selections OSC SEL OSC IN Low External Clock Input Low External Capacitor Floating or High Low Floating or High Floating or High NOTE With the OSC SEL pin low, OSC IN can be driven by an external clock signal external capacitor can be connected between OSC IN and GND. The nominal internal oscillator frequency is 10 ...
Page 7
... CE Gating and RAM Write Protection (ADM697) The ADM697 contains memory protection circuitry which ensures the integrity of data in memory by preventing write operations when LL is below the threshold voltage. When greater than 1 buffered replica OUT with propagation delay. When LL ...
Page 8
... ADM696/ADM697–Typical Performance Curves 5.00 4.95 4.90 SLOPE = 1.5Ω 4.85 4. – mA OUT Figure 8. V vs. I Normal Operation OUT OUT 2.80 2.79 2.78 SLOPE = 20Ω 2.77 2.76 0 200 400 600 I – µA OUT Figure 9. V vs. Battery Backup OUT 1.303 1.302 1.301 1.300 1.299 TEMPERATURE – Figure 10. PFI Input Threshold vs. Temperature ...
Page 9
... With D1 inserted, the internal timeout is set at 100 ms while with D2 inserted the timeout is set at 1.6 s. WATCHDOG STROBE CONTROL INPUT Figure 17a. Programming the Watchdog Input CONTROL INPUT* Figure 17b. Programming the Watchdog Input –9– ADM696/ADM697 +5V 7805 1.3V PFO PFI µP NMI ADM69x ...
Page 10
... ADM696/ADM697 Replacing the Back-Up Battery When changing the back-up battery with system power on, spu- rious resets can occur when the battery is removed. This occurs because the leakage current flowing out of the V charge up the stray capacitance. If the voltage on V within reset pulse is generated. ...
Page 11
... SEATING REV. 0 RAM Write Protection The ADM697 CE CMOS RAM. CE reset threshold goes high, independent of the logic level at CE the microprocessor from writing erroneous data into RAM dur- ing power-up, power-down, brownouts and momentary power interruptions. OUTLINE DIMENSIONS Dimensions shown in inches and (mm) ...
Page 12
–12– ...