Features: • Selectable watchdog timer (0.25s, 0.75s, 1.75s, off)
• Power on reset (250ms)
• Programmable low voltage reset
• 2 polled alarms
-Settable on the second, minute, hour, day,
month, or day of the week
• 2-wire interface interoperable with I
2
C
-400kHz data transfer rate
• Secondary power supply input with internal
switch-over circuitry
• Low power CMOS
-<1A operating current
-<3mA active current during program
-<400A active current during data read
• Single byte write capability
• Typical nonvolatile write cycle time: 5ms
• High reliability
• Small package options
-8-lead SOIC package, 8-lead TSSOP packagePinout
SpecificationsTemperature under bias ........................ -65 to +135°C
Storage temperature ............................. -65 to +150°C
Voltage on any pin (respect to ground)......-1.0V to 7.0V
DC output current................................................... 5 mA
Lead temperature (soldering, 10 sec) ................ 300°C
Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only; the functional operation of the device (at these or any other conditions above those indicated in the operational sections of this specification) is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
DescriptionThe X1202 is a Real Time Clock with Clock/Calendar/CPU Supervisor circuits and two polled alarms. The dual port clock and alarm registers allow the clock to operate,without loss of accuracy, even during read and write operations.
The clock/calendar provides functionality that is controllable and readable through a set of registers. The clock, using a low-cost 32.768kHz crystal input, accurately tracks the time in seconds, minutes, hours, date,day, month and years. The X1202 has leap year correction and automatic adjustment for months with less than 31 days.
The X1202 provides a watchdog timer with 3 selectable time out periods and off. The watchdog activates a RESET pin when it expires. The reset also goes active when VCC drops below a fixed trip point. There are two alarms where a match is monitored by polling status bits.
The X1202 offers a backup power input pin. This VBACK pin allows the X1202 to be backed up by a nonrechargeable battery. The RTC is fully operational from 1.8 to 5.5 volts.
X1202 Data Sheet
