Analog Devices Inc./Maxim Integrated

The LT1676 is a wide input range, high efficiency Buck (step-down) switching regulator. The monolithic die includes all oscillator, control and protection circuitry. The part can accept input voltages as high as 60V and contains an output switch rated at 700mA peak current. Current mode control offers excellent dynamic input supply rejection and short-circuit protection.The LT1676 contains several features to enhance efficiency. The internal control circuitry is normally powered via the VCCpin, thereby minimizing power drawn directly from the VINsupply (see Applications Information). The action of the LT1676 switch circuitry is also load dependent. At medium to high loads, the output switch circuitry maintains high rise time for good efficiency. At light loads, rise time is deliberately reduced to avoid pulse skipping behavior.The available SO-8 package and 100kHz switching frequency allow for minimal PC board area requirements.ApplicationsAutomotive DC/DC ConvertersTelecom 48V Step-Down ConvertersCellular Phone Battery Charger AccessoriesIEEE 1394 Step-Down Converters

The LT1677 features the lowest noise performance available for a rail-to-rail operational amplifier: 3.2nV/√Hzwideband noise, 1/f corner frequency of 13Hz and 90nV peak-to-peak 0.1Hz to 10Hz noise. Low noise is combined with outstanding precision: 20µV offset voltage and 0.2µV/°C drift, 130dB common mode and power supply rejection and 7.2MHz gain bandwidth product. The common mode range exceeds the power supply by 100mV.The voltage gain of the LT1677 is extremely high, 19 million (typical) driving a 10k load.In the design, processing and testing of the device, particular attention has been paid to the optimization of the entire distribution of several key parameters. Consequently, the specifications have been spectacularly improved compared to competing rail-to-rail amplifiers.ApplicationsLow Noise Signal ProcessingMicrovolt Accuracy Threshold DetectionStrain Gauge AmplifiersTape Head PreamplifiersDirect Coupled Audio Gain StagesInfrared DetectorsBattery-Powered Microphones

The LT1678/LT1679 are dual/quad rail-to-rail op amps offering both low noise and precision: 3.9nV/√Hzwideband noise, 1/f corner frequency of 4Hz and 90nV peak-to-peak 0.1Hz to 10Hz noise are combined with outstanding precision: 100µV maximum offset voltage, greater than 100dB common mode and power supply rejection and 20MHz gain bandwidth product. The LT1678/LT1679 bring precision as well as low noise to single supply applications as low as 3V. The input range exceeds the power supply by 100mV with no phase inversion while the output can swing to within 170mV of either rail.The LT1678/LT1679 are offered in the SO-8 and SO-14 packages. A full set of matching specifications are also provided, facilitating their use in matching dependent applications such as a two op amp instrumentation amplifier design. The LT1678/LT1679 are specified for supply voltages of ±15V, single 5V as well as single 3V. For a single amplifier with similiar performance, see the LT1677 data sheet.ApplicationsStrain Gauge AmplifiersPortable MicrophonesBattery-Powered Rail-to-Rail InstrumentationLow Noise Signal ProcessingMicrovolt Accuracy Threshold DetectionInfrared Detectors