The LTC2421/LTC2422 are 1- and 2-channel 2.7V to 5.5V micropower 20-bit analog-to-digital converters with an integrated oscillator, 8ppm INL and 1.2ppm RMS noise. These ultrasmall devices use delta-sigma technology and a new digital filter architecture that settles in a single cycle. This eliminates the latency found in conventional ∆Σ converters and simplifies multiplexed applications.

Through a single pin, the LTC2421/LTC2422 can be configured for better than 110dB rejection at 50Hz or 60Hz ±2%, or can be driven by an external oscillator for a user defined rejection frequency in the range 1Hz to 120Hz. The internal oscillator requires no external frequency setting components.

These converters accept an external reference voltage from 0.1V to V_CC. With an extended input conversion range of –12.5% V_REF to 112.5% V_REF (V_REF = FS_SET – ZS_SET), the LTC2421/LTC2422 smoothly resolve the offset and overrange problems of preceding sensors or signal conditioning circuits.

The LTC2421/LTC2422 communicate through a 2- or 3-wire digital interface that is compatible with SPI and MICROWIRE^™ protocols.

 

Applications

• Weight Scales
• Direct Temperature Measurement
• Gas Analyzers
• Strain Gauge Transducers
• Instrumentation
• Data Acquisition
• Industrial Process Control

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.