The DS1340 is a real-time clock (RTC)/calendar that is pin compatible and functionally equivalent to the ST M41T00, including the software clock calibration. The device additionally provides trickle-charge capability on the VBACKUP pin, a lower timekeeping voltage, and an oscillator STOP flag. Block access of the register map is identical to the ST device. Two additional registers, which are accessed individually, are required for the trickle charger and flag. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. A built-in power-sense circuit detects power failures and automatically switches to the backup supply. The device is programmed serially through an I²C bidirectional bus.ApplicationsMedical EquipmentPoint-of-Sale EquipmentPortable InstrumentationTelecommunications

The DS1340 is a real-time clock (RTC)/calendar that is pin compatible and functionally equivalent to the ST M41T00, including the software clock calibration. The device additionally provides trickle-charge capability on the VBACKUP pin, a lower timekeeping voltage, and an oscillator STOP flag. Block access of the register map is identical to the ST device. Two additional registers, which are accessed individually, are required for the trickle charger and flag. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. A built-in power-sense circuit detects power failures and automatically switches to the backup supply. The device is programmed serially through an I²C bidirectional bus.ApplicationsMedical EquipmentPoint-of-Sale EquipmentPortable InstrumentationTelecommunications

The DS1374 is a 32-bit binary counter designed to continuously count time in seconds. An additional counter generates a periodic alarm or serves as a watchdog timer. If disabled, this counter can be used as 3 bytes of nonvolatile (NV) RAM. Separate output pins are provided for an interrupt and a square wave at one of four selectable frequencies. A precision temperature-compensated reference and comparator circuit monitor the status of VCC to detect power failures, provide a reset output, and automatically switch to the backup supply when necessary.Additionally, the reset pin is monitored as a pushbutton input for externally generating a reset. The device is programmed serially through an I²C serial interface.ApplicationsMedical EquipmentPoint-of-Sale EquipmentPortable InstrumentationTelecommunications

The DS1501/DS1511 are full-function, year 2000-compliant real-time clock/calendars (RTCs) with an RTC alarm, watchdog timer, power-on reset, battery monitors, 256 bytes NV SRAM, and a 32.768kHz output. User access to all registers within the DS1501/DS1511 is accomplished with a byte-wide interface, as shown in Figure 8. The RTC registers contain century, year, month, date, day, hours, minutes, and seconds data in 24-hour binary-coded decimal (BCD) format. Corrections for day of month and leap year are made automatically.ApplicationsBattery-Backed SystemsConsumer ElectronicsOffice EquipmentRemote SystemsTelecom Switches

The DS1308 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV RAM. Address and data are transferred serially through an I²C interface. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator. The DS1308 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply, maintaining time and date operation.ApplicationsConsumer Electronics (Set-Top Box, Digital Recording, Network Appliance)Handhelds (GPS, POS Terminal)Medical (Glucometer, Medicine Dispenser)Office Equipment (Fax/Printer, Copier)Other (Utility Meter, Vending Machine, Thermostat, Modem)Telecommunications (Router, Switcher, Server)

The DS1343/DS1344 low-current real-time clocks (RTCs) are timekeeping devices that provide an extremely low standby current, permitting longer life from a backup supply source. The devices also support high-ESR crystals, broadening the pool of usable crystals for the devices. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either 24-hour or 12-hour format with an active-low AM/PM indicator.Address and data are transferred serially through an SPI™ or 3-wire interface. Two programmable time-of-day alarms are provided. Each alarm can generate an interrupt on a combination of seconds, minutes, hours, and day. Don't-care states can be inserted into one or more fields if it is desired for them to be ignored for the alarm condition. The time-of-day alarms can be programmed to assert two different interrupt outputs, or they can be combined to assert one common interrupt output. Both interrupt outputs operate when the device is powered by either VCC or VBAT.The devices are available in a lead-free/RoHS-compliant, 20-pin TSSOP or 14-pin TDFN package, and support a -40°C to +85°C extended industrial temperature range.ApplicationsEmbedded TimestampingHandheld DevicesMedicalTelematics

The DS1343/DS1344 low-current real-time clocks (RTCs) are timekeeping devices that provide an extremely low standby current, permitting longer life from a backup supply source. The devices also support high-ESR crystals, broadening the pool of usable crystals for the devices. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either 24-hour or 12-hour format with an active-low AM/PM indicator.Address and data are transferred serially through an SPI™ or 3-wire interface. Two programmable time-of-day alarms are provided. Each alarm can generate an interrupt on a combination of seconds, minutes, hours, and day. Don't-care states can be inserted into one or more fields if it is desired for them to be ignored for the alarm condition. The time-of-day alarms can be programmed to assert two different interrupt outputs, or they can be combined to assert one common interrupt output. Both interrupt outputs operate when the device is powered by either VCC or VBAT.The devices are available in a lead-free/RoHS-compliant, 20-pin TSSOP or 14-pin TDFN package, and support a -40°C to +85°C extended industrial temperature range.ApplicationsEmbedded TimestampingHandheld DevicesMedicalTelematics

The Maxim ICM7555 and ICM7556 are respectively singleand dual general-purpose RC timers capable of generatingaccurate time delays or frequencies. The primaryfeature is an extremely low supply current, making thisdevice ideal for battery-powered systems. Additional featuresinclude low THRESHOLD, active-low TRIGGER, and active-low RESETcurrents, a wide operating supply voltage range, andimproved performance at high frequencies.These CMOS low-power devices offer significant performanceadvantages over the standard 555 and 556 bipolartimers. Low-power consumption, combined with the virtuallynonexistent current spike during output transitions, makethese timers the optimal solution in many applications.ApplicationsMissing Pulse DetectorPrecision TimingPulse GeneratorPulse Position ModulationPulse-Width ModulationSequential TimingTime Delay Generation

The DS3231M is a low-cost, extremely accurate, I2C real-time clock (RTC). The device incorporates a battery input and maintains accurate timekeeping when main power to the device is interrupted. The integration of the microelectromechanical systems (MEMS) resonator enhances the long-term accuracy of the device and reduces the piece-part count in a manufacturing line. The DS3231M is available in the same footprint as the popular DS3231 RTC.The RTC maintains seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with an active-low AM/PM indicator. Two programmable time-of-day alarms and a 1Hz output are provided. Address and data are transferred serially through an I2C bidirectional bus. A precision temperature-compensated voltage reference and comparator circuit monitors the status of VCC to detect power failures, to provide a reset output, and to automatically switch to the backup supply when necessary. Additionally, the active-low RST pin is monitored as a pushbutton input for generating a microprocessor reset. See the Block Diagram in the full data sheet for more details.ApplicationsIndustrial ApplicationsPower Meters

The LTC6948 is a high performance, low noise, 6.39GHz phase-locked loop (PLL) with a fully integrated VCO, including a reference divider, phase-frequency detector (PFD), ultralow noise charge pump, fractional feedback divider, and VCO output divider.The fractional divider uses an advanced, 4th order ΔΣ modulator which provides exceptionally low spurious levels. This allows wide loop bandwidths, producing extremely low integrated phase noise values.The programmable VCO output divider, with a range of 1 through 6, extends the output frequency range.Applications Wireless Basestations (LTE, WiMAX, W-CDMA, PCS) Microwave Data Links Military and Secure Radio Test and Measurement