LTC2637CMS-HMX8#PBF

Overview

The LTC2637CMS-HMX8#PBF is an octal 8-bit voltage-output digital-to-analog converter from Analog Devices. It features a selectable internal or external reference, with the H-grade variant providing a 4.096V full-scale output when using the internal reference. The device operates on a single 4.5V to 5.5V supply and communicates via a 2-wire I2C-compatible serial interface supporting standard (100kHz) and fast (400kHz) modes. It includes double-buffered data latches and a power-on reset circuit configured to reset to mid-scale in external reference mode. The component is housed in a 16-lead MSOP package.

Feature Summary

• Octal 8-bit resolution with rail-to-rail buffered outputs
• Integrated 10ppm/°C precision reference yielding 4.096V full-scale output
• Ultralow DAC-to-DAC crosstalk (<3nV•s)
• Guaranteed monotonic operation over –40°C to 125°C temperature range

Applications

• Mobile communications
• Process control and industrial automation
• Automatic test equipment
• Portable equipment
• Automotive systems
• Optical networking

Procurement Notes

Verify the specific suffix configuration against the datasheet ordering guide. The CMS designation indicates a commercial temperature grade (0°C to 70°C), while the H suffix in the base model typically denotes automotive grade (-40°C to 125°C). Confirm that the intended operating environment aligns with the C-grade specification. Ensure the power-on reset behavior matches the MX suffix requirement for external reference mid-scale initialization.

Selection Notes

Select this part for applications requiring multiple low-cost, low-power voltage outputs controlled by a simple I2C bus. The 8-bit resolution suits general-purpose control tasks where high precision is not critical. Consider the H-grade variants if the application requires operation beyond the commercial temperature range of 0°C to 70°C. Verify that the 4.5V minimum supply voltage for the H-reference configuration is compatible with the system power rails.

Part Context

This component belongs to the LTC2637 family, which offers 12-, 10-, and 8-bit resolutions in both DFN and MSOP packages. The family shares common architectural features such as the I2C interface and integrated reference options. The CMS-HMX8#PBF specifically combines the commercial temperature grade with the 8-bit resolution and the H-grade reference voltage capability, offering a balance of performance and cost for multi-channel applications.

Replacement Considerations

Direct substitutes within the same family include LTC2637CMS-HMI8#PBF (different power-on reset behavior) and LTC2637CMS-LZ8#PBF (lower voltage range). Cross-family replacements like the LTC2638 offer similar functionality but may differ in pinout or feature set. Verify package compatibility and electrical specifications before substitution.