Features: • Monitoring voltages: 5V to 9V
• Independent core voltage monitor
• Triple 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 VCC = 1V
-Monitor three separate voltages
• Fault detection register
• Selectable power-on reset timeout (0.05s, 0.2s, 0.4s, 0.8s)
• Selectable watchdog timer interval (25ms, 200ms, 1.4s or off)
• Debounced manual reset input
• Low power CMOS
-25µA typical standby current, watchdog on
-6µA typical standby current, watchdog off
• Memory security
• 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 0, or 1/2, of EEPROM
• 400kHz 2-wire interface
• 2.7V to 5.5V power supply operation
• Available packages
-14-lead SOIC, TSSOP
Application• Communication Equipment
-Routers, Hubs, Switches
-Disk Arrays, Network Storage
• Industrial Systems
-Process Control
-Intelligent Instrumentation
• Computer Systems
-Computers
-Network ServersPinout
SpecificationsTemperature under bias ....................... -65 to +135
Storage temperature ............................ -65 to +150
Voltage on any pin with
respect to VSS ........................................... -1.0V to +7V
D.C. output current ..................................................5mA
Lead temperature (soldering, 10 seconds)............ 300
Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only; functional operation of the device (at these or any other conditions above those listed in the operational sections of this specification) is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
DescriptionThe X40430, X40431, X40434, X40435 combines power-on reset control, watchdog timer, supply voltage supervision, second and third voltage supervision, manual reset, and Block Lock™ protect serial EEPROM in one package. This combination lowers system cost, reduces board space requirements, and increases reliability.
Applying voltage to VCC of X40435 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 VCC detection circuitry of X40435 protects the user's system from low voltage conditions, resetting the system when VCC falls below the minimum VTRIP1 point. RESET/RESET is active until VCC returns to proper operating level and stabilizes. A second and third 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, Intersil's unique circuits of X40435 allows the threshold for either voltage monitor to be reprogrammed to meet specific system level requirements or to fine-tune the threshold for applications requiring higher precision.
A manual reset input of X40435 provides debounce circuitry for minimum reset component count.
The Watchdog Timer of X40435 provides an independent protection mechanism for microcontrollers. When the microcontroller fails to restart a timer within a selectable time out interval, the device activates theWDO 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 X40435 is a CMOS Serial EEPROM array with Intersil'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 X40435 utilizes Intersil's proprietary Direct Write™ cell, providing a minimum endurance of 100,000 cycles and a minimum data retention of 100 years.
X40435 Data Sheet
