Analog Devices Inc./Maxim Integrated

The LTC6955 is a high performance, ultralow jitter, fanout clock buffer with eleven outputs. Its 4-pin parallel control port allows for multiple output setups, enabling any number between three and eleven outputs, as well as a complete shutdown. The parallel port also provides the ability to invert the output polarity of alternating outputs, simplifying designs with top and bottom board routing. Each of the CML outputs can run from DC to 7.5GHz. The LTC6955-1 replaces one output buffer with a divideby-2 frequency divider, allowing it to drive Analog Devices’ LTC6952 or LTC6953 to generate JESD204B subclass 1 SYSREF signals. These SYSREFs can pair with ultralow jitter device clocks from the LTC6955-1, which can run at frequencies up to 7.5GHz.ApplicationsHigh Performance Data Converter ClockingSONET, Fibre Channel, GigE Clock DistributionLow Skew and Jitter Clock and Data FanoutWireless and Wired CommunicationsSingle-Ended to Differential Conversion

The LTC6957-1/LTC6957-2/LTC6957-3/LTC6957-4 is a family of very low phase noise, dual output AC signal buffer/driver/logic level translators. The input signal can be a sine wave or any logic level (≤2VP-P). There are four members of the family that differ in their output logic signal type as follows:LTC6957-1: LVPECL Logic OutputsLTC6957-2: LVDS Logic OutputsLTC6957-3: CMOS Logic, In-Phase OutputsLTC6957-4: CMOS Logic, Complementary OutputsThe LTC6957 will buffer and distribute any logic signal with minimal additive noise, however, the part really excels at translating sine wave signals to logic levels. The early amplifier stages have selectable lowpass filtering to minimize the noise while still amplifying the signal to increase its slew rate. This input stage filtering/noise limiting is especially helpful in delivering the lowest possible phase noise signal with slow slewing input signals such as a typical 10MHz sine wave system reference.ApplicationsSystem Reference Frequency DistributionHigh Speed ADC, DAC, DDS Clock DriverMilitary and Secure RadioLow Noise Timing TriggerBroadband Wireless TransceiverHigh Speed Data AcquisitionMedical ImagingTest and Measurement

The LTC699 provides power supply monitoring for microprocessor-based systems. The features include microprocessor reset and watchdog timing. Precise internal voltage reference and comparator circuit monitor the power supply line. When an out-of-tolerance condition occurs, theRESEToutput is forced to active low. In addition, theRESEToutput is guaranteed to remain logic low even with VCCas low as 1V.An internal watchdog timer is also available, which forces theRESEToutput to active low when the watchdog input is not toggled prior to the time-out period of 1.6 seconds.The LTC699 is offered in DIP and surface mount packages.ApplicationsCritical µP Power MonitoringIntelligent InstrumentsComputers and ControllersAutomotive Systems

The LTC6990 is a precision silicon oscillator with a programmable frequency range of 488Hz to 2MHz. It can be used as a fixed-frequency or voltage-controlled oscillator (VCO). The LTC6990 is part of the TimerBlox®family of versatile silicon timing devices.A single resistor, RSET, programs the LTC6990’s internal master oscillator frequency. The output frequency is determined by this master oscillator and an internal frequency divider, NDIV, programmable to eight settings from 1 to 128.Optionally, a second resistor at the SET input provides linear voltage control of the output frequency and can be used for frequency modulation. A narrow or wide VCO tuning range can be configured by the appropriate selection of the two resistors.The LTC6990 includes an enable function that is synchronized with the master oscillator to ensure clean, glitch-free output pulses. The disabled output can be configured to be high impedance or forced low.For easy configuration of the LTC6990, use theTimerBlox LTC6990: Voltage Controlled Oscillator Web-Based Design Tool.ApplicationsLow Cost Precision Programmable OscillatorVoltage-Controlled OscillatorHigh Vibration, High Acceleration EnvironmentsReplacement for Fixed Crystal and Ceramic OscillatorsPortable and Battery-Powered Equipment

The LTC6991 is a silicon oscillator with a programmable period range of 1.024ms to 9.54 hours (29.1µHz to 977Hz), specifically intended for long duration timing events. The LTC6991 is part of the TimerBlox®family of versatile silicon timing devices.A single resistor, RSET, programs the LTC6991’s internal master oscillator frequency. The output clock period is determined by this master oscillator and an internal frequency divider, NDIV, programmable to eight settings from 1 to 221.In normal operation, the LTC6991 oscillates with a 50% duty cycle. A reset function is provided to truncate the pulse (reducing the duty cycle). The reset pin can also be used to prevent the output from oscillating.The RST and OUT pins can be configured for active-low or active-high operation using a polarity function.POL BitRST PinOutput State00Oscillating010 (reset)101 (reset)11OscillatingApplications"Heartbeat" TimersWatchdog TimersIntervalometersPeriodic "Wake-Up" CallHigh Vibration, High Acceleration EnvironmentsPortable and Battery-Powered Equipment

The LTC6994 is a programmable delay block with a range of 1µs to 33.6 seconds. The LTC6994 is part of the TimerBlox®family of versatile silicon timing devices.A single resistor, RSET, programs an internal master oscillator frequency, setting the LTC6994’s time base. The input-to-output delay is determined by this master oscillator and an internal clock divider, NDIV, programmable to eight settings from 1 to 221.The output (OUT) follows the input (IN) after delaying the rising and/or falling transitions. The LTC6994-1 will delay the rising or falling edge. The LTC6994-2 will delay both transitions, and adds the option to invert the output.The LTC6994 also offers the ability to dynamically adjust the delay time via a separate control voltage.ApplicationsNoise Discriminators/Pulse QualifiersDelay MatchingSwitch DebouncingHigh Vibration, High Acceleration EnvironmentsPortable and Battery-Powered Equipment

The LTC6995 is a silicon oscillator with a programmable period range of 1.024ms to 9.54 hours (29.1μHz to 977Hz), specifically intended for long duration timing events. The LTC6995 is part of the TimerBlox®family of versatile silicon timing devices.A single resistor, RSET, programs the LTC6995’s internal master oscillator frequency. The output clock period is determined by this master oscillator and an internal frequency divider, NDIV, programmable to eight settings from 1 to 221.When oscillating, the LTC6995 generates a 50% duty cycle square wave output. A reset function is provided to stop the master oscillator and clear internal dividers. Removing reset initiates a full output clock cycle which is useful for programmable power-on reset and watchdog timer applications.The LTC6995 has two versions of reset functionality. The reset input is active high for the LTC6995-1 and active low for the LTC6995-2. The polarity of the output when reset is selectable for both versions.ApplicationsPower-On Reset TimerLong Time One Shot"Heartbeat" TimersWatchdog TimersPeriodic "Wake-Up" CallHigh Vibration, High Acceleration Environments