The X40410/11/14/15 combines power-on reset control, watchdog timer, supply voltage supervision, and secondary voltage supervision, and Block Lock™ protect serial EEPROM in one package. This combination lowers system cost, reduces board space requirements, and increases reliability.

Applying voltage to V_CC activates the power on reset circuit which holds RESET/RESET active for a period of time. This allows the power supply and system oscillator to stabilize before the processor can execute code.

Low V_CC detection circuitry protects the user's system from low voltage conditions, resetting the system when V_CC falls below the minimum V_TRIP1 point. RESET/ RESET is active until V_CC returns to proper operating level and stabilizes. A second voltage monitor circuit tracks the unregulated supply to provide a power fail warning or monitors different power supply voltage. Three common low voltage combinations are available, however, Xicor's unique circuits allows the threshold for either voltage monitor to be reprogrammed to meet special needs or to fine-tune the threshold for applications requiring higher precision.

The Watchdog Timer provides an independent protection mechanism for microcontrollers. When the microcontroller fails to restart a timer within a selectable time out interval, the device activates the WDO signal. The user selects the interval from three preset values. Once selected, the interval does not change, even after cycling the power.

The memory portion of the device is a CMOS Serial EEPROM array with Xicor's Block Lock protection. The array is internally organized as x 8. The device features a 2-wire interface and software protocol allowing operation on an I²C^® bus.

The device utilizes Xicor's proprietary Direct Write™ cell, providing a minimum endurance of 100,000 cycles and a minimum data retention of 100 years.

• Dual voltage detection and reset assertion
  • Standard reset threshold settings See Selection table on page 2.
  • Adjust low voltage reset threshold voltages using special programming sequence
  • Reset signal valid to V_CC = 1V
  • Monitor three voltages or detect power fail
• Independent Core Voltage Monitor (V2MON)
• Fault detection register
• Selectable power on reset timeout (0.05s, 0.2s, 0.4s, 0.8s)
• Selectable watchdog timer interval (25ms, 200ms, 1.4s, off)
• Low power CMOS
  • 25µA typical standby current, watchdog on
  • 6µA typical standby current, watchdog off
• 4Kbits of EEPROM
  • 16 byte page write mode
  • 5ms write cycle time (typical)
• Built-in inadvertent write protection
  • Power-up/power-down protection circuitry
  • Block lock protect none or 1/2 of EEPROM
• 400kHz 2-wire interface
• 2.7V to 5.5V power supply operation
• Available packages
  • 8-lead SOIC, TSSOP

• Communication Equipment
  • Routers, Hubs, Switches
  • Disk Arrays, Network Storage
• Industrial Systems
  • Process Control
  • Intelligent Instrumentation
• Computer Systems
  • Computers
  • Network Servers