LTC2463 ADC Integrates Precision Reference

Linear Technology has introduced the LTC2463, a 16-bit delta sigma ADC that integrates a precision reference in 12-lead 3 x 3mm DFN and 4 x 5mm MSOP packages. With the device's integrated reference (2ppm/C typical, 10ppm/C maximum), the LTC2463 allows precise measurements with no need for an external reference. The LTC2463 communicates via a two-wire I2C interface and is a complete analogue solution for portable sensors, compact systems or power-supply monitoring.

Operating from a single 2.7 to 5.5V supply, the LTC2463 measures a +/-1.25V differential input range at output rates up to 60Hz, enabling measurement of temperature, pressure, voltage or other low-frequency sensor signals. The LTC2463 achieves 16-bit DC performance of 1LSB (typical) integral nonlinearity error, 2.2uVRMS transition noise and 0.01 per cent gain error (typical). This ADC has an internal oscillator, another space-saving feature.

The LTC2463 draws 2.5mA (max) supply current at the 60Hz maximum sample rate with the internal reference active. After each conversion, the ADC enters nap mode, reducing supply current to less than 1.5mA. Supply current can be further reduced to less than 2uA (max) in sleep mode. The LTC2463 incorporates an input sampling network that reduces the dynamic input current to less than 50nA, enabling a range of external-input-protection and filter circuits. It is offered alongside the LTC2461, a 16-bit I2C ADC that measures single-ended inputs between 0 and 1.25V.

MAX11040 Simultaneous-Sampling ADC Launched

Maxim Integrated Products has introduced the MAX11040 four-channel 24-bit simultaneous-sampling ADC. Developed to enable simplicity in system design, up to eight MAX11040 devices can be daisy-chained to provide a sampling capacity of up to 32 channels. The MAX11040 achieves this high capacity and scalability with a cascadable SPI/QSPI/Microwire interface, which eliminates the complexity of using individual chip-select inputs to control each ADC.

Because all eight MAX11040 devices can be accessed using only a single chip-select input, from the host processor's point of view, the control logic remains the same regardless if there are only four or as many as 32 channels. The MAX11040 provides compensation for phase shifts caused by resistor dividers, transformers, or filters at the analogue inputs through a programmable delay of 0-333 microseconds.

Together with a minimum of 90dB of SINAD and 91dB of SFDR, these features make the MAX11040 ideal for industrial power-grid protection equipment, as well as medical EKG/EEG equipment and other applications that require accurate conversions of simultaneously sampled channels between 0.25ksps and 64ksps.

Additionally, overvoltage protection on the analogue inputs protects the MAX11040 from voltages as large as +/-6V when referenced to the device's analogue ground, simplifying design and reducing cost. The MAX11040 is available in a lead-free, 38-pin TSSOP package.