Analog Devices Inc./Maxim Integrated

The LTC1144 is a monolithic CMOS switched-capacitor voltage converter. It performs supply voltage conversion from positive to negative from an input range of 2V to 18V, resulting in complementary output voltages of –2V to –18V. Only two noncritical external capacitors are needed for the charge pump and charge reservoir functions.The converter has an internal oscillator that can be overdriven by an external clock or slowed down when connected to a capacitor. The oscillator runs at a 10kHz frequency when unloaded. A higher frequency outside the audio band can also be obtained if the Boost Pin is tied to V+. TheSHDNpin reduces supply current to 8μA and can be used to save power when the converter is not in use.The LTC1144 contains an internal oscillator, divide-by-two, voltage level shifter, and four power MOSFETs. A special logic circuit will prevent the power N-channel switch substrate from turning on.ApplicationsConversion of 15V to ±15V SuppliesInexpensive Negative SuppliesData Acquisition SystemsHigh Voltage Upgrade to LTC1044 or 7660Voltage Division and MultiplicationsAutomotive ApplicationsBattery Systems with Wall Adapter/Charger

The LTC1148 series is a family of synchronous stepdown switching regulator controllers featuring automatic Burst Mode™operation to maintain high efficiencies at low output currents. These devices drive external complementary power MOSFETs at switching frequencies up to 250kHz using a constant off-time current-mode architecture providing constant ripple current in the inductor.The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 18V (20V maximum). Constant off-time architecture provides low dropout regulation limited by only the RDS(ON)of the external MOSFET and resistance of the inductor and current sense resistor.The LTC1148 series combines synchronous switching for maximum efficiency at high currents with an automatic low current operating mode, called Burst Mode operation, which reduces switching losses. Standby power is reduced to only 2mW at VIN= 10V (at IOUT= 0). Load currents in Burst Mode operation are typically 0mA to 300mA.For operation up to 48V input, see the LTC1149 and LTC1159 data sheets and Application Note 54.ApplicationsNotebook and Palmtop ComputersPortable InstrumentsBattery-Operated Digital DevicesCellular TelephonesDC Power Distribution SystemsGPS Systems

The LTC1150 is a high-voltage, high-performance zero-drift operational amplifier. The two sample-and-hold capacitors usually required externally by other chopper amplifiers are integrated on-chip. Further, LTC’s proprietary high-voltage CMOS structures allow the LTC1150 to operate at up to 32V total supply voltage.The LTC1150 has an offset voltage of 0.5µV, drift of 0.01µV/°C, 0.1Hz to 10Hz input noise voltage of 1.8µVP-Pand a typical voltage gain of 180dB. The slew rate of 3V/µs and a gain bandwidth productof 2.5MHz are achieved with 0.8mA of supply current. Overload recovery times from positive and negative saturation conditions are 3ms and 20ms, respectively.For applications demanding low power consumption, Pin 1 can be used to program the supply current. Pin 5 is an optional AC-coupled clock input, useful for synchronization.The LTC1150 is available in standard 8-lead, plastic dual-in-line package, as well as an 8-lead SO package. The LTC1150 can be a plug-in replacement for most standard bipolar op amps with significant improvement in DC performance.ApplicationsStrain Gauge AmplifiersElectronic ScalesMedical InstrumentationThermocouple AmplifiersHigh Resolution Data Acquisition