MAX690A-MAX805L MAXIM [Maxim Integrated Products], MAX690A-MAX805L Datasheet
MAX690A-MAX805L
Related parts for MAX690A-MAX805L
MAX690A-MAX805L Summary of contents
Page 1
... MAX692A/MAX802M generate a reset below 4.40V. The MAX802L/MAX802M guaran- tee power-fail accuracies to ±2%. The MAX805L is the same as the MAX690A except that RESET is provided instead of RESET. All parts are available in 8-pin DIP and SO packages. The MAX690A/MAX802L are pin compatible with the MAX690 and MAX694 ...
Page 2
... 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 = 4.75V to 5.5V for MAX690A/MAX802L/MAX805L unless otherwise noted ...
Page 3
... Microprocessor Supervisory Circuits ELECTRICAL CHARACTERISTICS (continued 4.75V to 5.5V for MAX690A/MAX802L/MAX805L unless otherwise noted.) A MIN MAX PARAMETER SYMBOL RESET Output Voltage t Watchdog Timeout WD t WDI Pulse Width WP WDI Input Threshold (Note 4) WDI Input Current PFI Input Threshold PFI Input Current ...
Page 4
... CC PFI T = +25°C A +1.2V 400ns/div MAX805L RESET RESPONSE TIME +5V + RESET 330pF GND +5V 0V 10k 330 s/div MAX690A RESET OUTPUT VOLTAGE vs. SUPPLY VOLTAGE + BATT T = +25° + RESET RESET RESET 330pF GND 0V 500ms/div ...
Page 5
... WDI is three-stated, or WDI sees a rising or falling edge. Reset Output. Whenever RESET is triggered, it pulses low for 200ms. It stays low when V is below the reset threshold (4.65V in the CC MAX690A/MAX802L and 4.4V in the MAX692A/MAX802M) and remains RESET low for 200ms after V rises above the reset threshold. A watchdog CC timeout also triggers RESET ...
Page 6
... Figure 1. Block Diagram _______________Detailed Description A microprocessor’s (µP’s) reset input starts the µ known state. When the µ unknown state, it should be held in reset. The MAX690A/MAX692A/MAX802L/ MAX802M assert reset during power-up and prevent code execution errors during power-down or brownout condi- tions. ...
Page 7
... SW4 + 0.1F Closed ( ) ARE FOR MAX805L ONLY. Closed Open Figure 4. Using a SuperCap as a Backup Power Source with a MAX690A/MAX802L/MAX805L and a +5V ±5% Supply than When V exceeds the reset threshold connected to CC the MAX690A/MAX692A/MAX802L/MAX802M/MAX805L substrate, regardless of the voltage applied to V (Figure 3). During this time, the diode (D1) between V and the substrate will conduct current from V Table 1 ...
Page 8
... SuperCap rapidly charges to within a diode drop of V However, after a long time, the diode leakage current will pull the SuperCap voltage SuperCap with the MAX690A/MAX802L/MAX805L, V may not exceed 4.75V + 0.6V = 5.35V. Use the SuperCap circuit of Figure 5 with a MAX692A or MAX802M and a ±10% supply. This circuit ensures that the SuperCap only charges ...
Page 9
... Motorola 68HC11 series, MAX690A/MAX692A/MAX802L/MAX802M RESET out- put. If, for example, the RESET output is driven high and the µP wants to pull it low, indeterminate logic lev- els may result. To correct this, connect a 4.7kΩ resis- tor between the RESET output and the µP reset I/ Figure 8 ...
Page 10
... Microprocessor Supervisory Circuits BUFFERED RESET TO OTHER SYSTEM COMPONENTS V CC MAX690A 4.7k MAX692A RESET RESET MAX802L MAX802M GND Figure 8. Interfacing to µPs with Bidirectional Reset I/O 10 ______________________________________________________________________________________ V CC GND ...
Page 11
... Microprocessor Supervisory Circuits ________________________ Minimum Nominal Nominal Reset Watchdog Reset Pulse Timeout Part Threshold Width Period Number (V) (ms) (sec) MAX690A/692A 4.65/4.40 140 1.6 MAX691A/693A 4.65/4.40 140/adj. 1.6/adj. MAX696 Adj. 35/adj. 1.6/adj. MAX697 Adj. 35/adj. 1.6/adj. MAX700 4.65/adj. 200 - MAX703/704 4.65/4.40 140 - MAX705/706 4.65/4.40 140 1.6 MAX706P 2.63 140 1 ...
Page 12
Microprocessor Supervisory Circuits __Ordering Information (continued) PART TEMP. RANGE MAX692ACPA 0°C to +70°C MAX692ACSA 0°C to +70°C MAX692AC/D 0°C to +70°C MAX692AEPA -40°C to +85°C MAX692AESA -40°C to +85°C MAX692AMJA -55°C to +125°C MAX802LCPA 0°C to +70°C MAX802LCSA 0°C to ...