LTC2637CMS-LZ8#PBF

Overview

The LTC2637CMS-LZ8#PBF is an octal 8-bit voltage-output digital-to-analog converter (DAC) from Analog Devices. It features a 14-lead DFN package and operates on a single 2.7V to 5.5V supply. The device includes an integrated precision reference providing a 2.5V full-scale output with a temperature coefficient of 10ppm/°C. Communication is handled via a 2-wire I2C-compatible serial interface supporting standard (100kHz) and fast (400kHz) modes. Key electrical specifications include a maximum integral nonlinearity (INL) error of ±0.5 LSB, a settling time of 3.5µs at ±1 LSB for 8-bit resolution, and a power-on reset function that defaults outputs to zero-scale.

Feature Summary

• Octal architecture with 8 independent 8-bit DAC channels in a compact 14-lead DFN package
• Integrated 2.5V precision reference with 10ppm/°C drift and selectable external reference input
• Rail-to-rail buffered outputs guaranteed monotonic over the operating temperature range
• Ultralow crosstalk between DACs (<3nV•s) and double-buffered data latches

Applications

• Mobile communications systems
• Process control and industrial automation
• Automatic test equipment
• Portable battery-powered equipment
• Automotive electronics
• Optical networking devices

Procurement Notes

Verify the specific ordering suffix LZ8 corresponds to the 8-bit resolution, zero-scale power-on reset, and commercial temperature grade (0°C to 70°C). Confirm the MSOP or DFN package variant matches the design requirements, as the CMS designation indicates a 16-lead MSOP package while the datasheet details both DE and MSOP options. Ensure the I2C address pins CA0, CA1, and CA2 are configured correctly for the target system bus.

Selection Notes

Select this component when multiple low-resolution voltage outputs are required in a space-constrained design. The 8-bit resolution suits applications where high precision is not critical but channel count is. Verify that the 2.5V internal reference range meets the signal swing requirements; otherwise, utilize the REF pin for an external reference. Check thermal constraints for the MSOP package if driving significant load currents near the supply rails.

Part Context

This part belongs to the LTC2637 family, which offers 12-, 10-, and 8-bit resolutions. The 'L' suffix denotes the 2.5V full-scale version powered by a 2.7V to 5.5V supply, distinct from the 'H' version which provides 4.096V full-scale and requires a 4.5V to 5.5V supply. The 'Z' suffix specifies the power-on reset behavior to zero-scale, differentiating it from 'MI' (mid-scale) or 'MX' (external reference mid-scale) variants.

Replacement Considerations

Direct substitutes within the same family include LTC2637CMS-LZ10#PBF (10-bit) and LTC2637CMS-LZ12#PBF (12-bit), provided higher resolution is acceptable. For different reset behaviors, consider LTC2637CMS-LMI8#PBF (mid-scale reset). Cross-package equivalents like the 14-lead DFN LTC2637CDE-LZ8#PBF offer identical electrical performance in a smaller footprint.