Analog Devices Inc./Maxim Integrated

The LT1101 establishes the following milestones: (1) It is the first micropower instrumentation amplifier, (2) It is the first single supply instrumentation amplifier, (3) It is the first instrumentation amplifier to feature fixed gains of 10 and/or 100 in low cost, space-saving 8-lead packages.The LT1101 is completely self-contained: no external gain setting resistor is required. The LT1101 combines its micropower operation (75µA supply current) with again error of 0.008%, gain linearity of 3ppm, gain drift of 1ppm/°C. The output is guaranteed to drive a 2k load to ±10V with excellent gain accuracy.Other precision specifications are also outstanding: 50µV input offset voltage, 130pA input offset current, and low drift (0.4µV/°C and 0.7pA/°C). In addition, unlike other instrumentation amplifiers, there is no output offset voltage contribution to total error.A full set of specifications are provided with ±15V dual supplies and for single 5V supply operation. The LT1101 can be operated from a single lithium cell or two Ni-Cad batteries. Battery voltage can drop as low as 1.8V, yet the LT1101 still maintains its gain accuracy. In single supply applications, both input and output voltages swing to within a few millivolts of ground. The output sinks current while swinging to ground—no external, power consuming pull down resistors are needed.ApplicationsDifferential Signal Amplification in Presence of Common Mode VoltageMicropower Bridge Transducer AmplifierThermocouplesStrain GaugesThermistorsDifferential Voltage-to-Current ConverterTransformer Coupled Amplifier4mA to 20mA Bridge Transmitter

The LT1105 Offline Switching Regulator is designed for high input voltage applications using an external FET switch. The LT1105 is available and its totem pole output drives the gate of an external FET. Unique design of the LT1105 eliminates the need for an optocoupler while still providing ±1% load and line regulation in a magnetic flux-sensed converter. This significantly simplifies the design of offline power supplies and reduces the number of components which must cross the isolation barrier to one, the transformer.The LT1105 current mode switching techniques are well suited to transformer isolated flyback and forward topologies while providing ease of frequency compensation with a minimum of external components.APPLICATIONSUp to 250W Isolated Mains ConverterUp to 50W Isolated Telecom ConverterFully Isolated Multiple OutputsDistributed Power Conversion Networks

The LT1107 is a versatile micropower DC/DC converter. The device requires only three external components to deliver a fixed output of 5V or 12V. Supply voltage ranges from 2V to 12V in step-up mode and to 30V in step-down mode. The LT1107 functions equally well in step-up, step-down, or inverting applications.The LT1107 is pin-for-pin compatible with the LT1111, but has a duty cycle of 70%, resulting in increased output current in many applications. The LT1107 can deliver 150mA at 5V from a 2AA cell input and 5V at 300mA from 24V in step-down mode. Quiescent current is just 320µA, making the LT1107 ideal for power-conscious battery operated systems. The 63kHz oscillator is optimized to work with surface mount inductors and capacitors.Switch current limit can be programmed with a single resistor. An auxiliary gain block can be configured as a low-battery detector, linear post regulator, undervoltage lock-out circuit, or error amplifier.ApplicationsPalmtop Computers3V to 5V, 5V to 12V Converters24V to 5V, 12V to 5V ConvertersLCD Bias GeneratorsPeripherals and Add-On CardsBattery Backup SuppliesCellular TelephonesPortable Instruments

The LT1108 is a versatile micropower DC/DC converter. The device requires only four external components to deliver a fixed output of 5V or 12V. Supply voltage ranges from 2V to 12V in step-up mode and to 30V in step-down mode.The LT1108 functions equally well in step-up, step-down, or inverting applications.The LT1108 is pin-for-pin compatible with the LT1173, but has a duty cycle of 70%, resulting in increased outputcurrent in many applications. The LT1108 can deliver 150mA at 5V from a 2 AA cell input and 5V at 300mA from 9V in step-down mode. Quiescent current is just 110µA, making the LT1108 ideal for power conscious battery-operated systems.Switch current limit can be programmed with a single resistor.An auxiliary gain block can be configured as a low battery detector, linear post regulator, under voltage lock-out circuit, or error amplifier.ApplicationsPalmtop Computers3V to 5V, 5V to 12V Converters9V to 5V, 12V to 5V ConvertersLCD Bias GeneratorsPeripherals and Add-On CardsBattery Backup SuppliesCellular Telephones

The LT1109 is a simple step-up DC/DC converter. Available in 8-pin SO, 3-lead TO-92 (fixed output only) or miniDIP packages, the devices require only three external components to construct a complete DC/DC converter. Current drain is just 320µA at no load, making the device ideal for cost-sensitive applications where standby current must be kept to a minimum.The LT1109-5 can deliver 5V at 100mA from a 3V input and the LT1109-12 can deliver 12V at 60mA from a 5V input. The 8-pin versions also feature a logic controlledSHUTDOWNpin that turns off the oscillator when taken low. The gated-oscillator design requires no frequency compensation components. The high frequency 120kHz oscillator permits the use of small surface mount inductors and capacitors. For a 5V to 12V at 120mA converter, see the LT1109A. For a 5V to 12V at 200mA converter with 20µA shutdown current, see the LT1301.ApplicationsFlash Memory VPP Generators3V to 5V Converters5V to 12V ConvertersDisk DrivesPC Plug-In CardsPeripheralsBattery-Powered Equipment

The LT1109A is a simple step-up DC/DC converter. The 8-pin DIP or SOIC devices require only four external components to construct a complete DC/DC converter. Current drain is just 360µA at no load, making the device ideal for cost-sensitive applications where standby current must be kept to a minimum.The LT1109A-12 can deliver 12V at over 150mA from a 5V supply, enough power to program four flash memory chips simultaneously. The LT1109A-5 can deliver 5V at up to 110mA from a 2V input. The devices feature a shutdown pin that turns off the oscillator when taken low. The gatedoscillator design requires no frequency compensation components. High frequency 120kHz operation permits the use of small surface mount inductors and capacitors.ApplicationsFlash Memory VPP Generators5V to 12V Converters3.3V to 12V ConvertersDisk DrivesPC Plug-In CardsPeripheralsBattery-Powered Equipment