LTC2642IDD-14#TRPBF

Overview

The LTC2642IDD-14#TRPBF is a 14-bit unbuffered voltage output digital-to-analog converter in a 10-lead 3mm × 3mm DFN package. It operates from a single 2.7V to 5.5V supply with a typical supply current of 120µA. The device features a 50MHz SPI-compatible serial interface and includes matched scaling resistors for bipolar operation with an external op amp. It guarantees monotonicity over temperature, with integral nonlinearity (INL) of ±1 LSB and differential nonlinearity (DNL) of ±0.5 LSB. Power-on reset sets the output to midscale, while the CLR pin asynchronously clears it to midscale.

Feature Summary

• 14-bit resolution with ±1 LSB INL and ±0.5 LSB DNL guaranteed over temperature
• Unbuffered voltage output drives loads >60kΩ directly
• Integrated matched scaling resistors enable bipolar output swing (-VREF to +VREF)
• Fast 1µs settling time to 16-bit accuracy with 0.5nV•sec glitch impulse

Applications

• Process control and industrial automation systems
• Automatic test equipment requiring high linearity
• Data acquisition systems needing low power consumption

Procurement Notes

Verify the ordering suffix #TRPBF indicates tape and reel packaging. Confirm the IDD suffix corresponds to the industrial temperature range of –40°C to 85°C. Ensure the 14-bit variant matches system resolution requirements. Check that the 10-lead DFN package fits the PCB footprint constraints. Validate that the bipolar configuration utilizes an external precision op amp as specified in the datasheet.

Selection Notes

Select this part when bipolar output capability is required without external resistor networks. The unbuffered output simplifies design but requires load resistance >60kΩ to maintain linearity. Compare against LTC2641 if zero-scale power-up is preferred over midscale. Consider the 16-bit version if higher precision is needed, noting the increased cost and potential performance trade-offs.

Part Context

This component belongs to the LTC2641/LTC2642 family of 16-/14-/12-bit DACs. The LTC2642 variant specifically includes internal scaling resistors for bipolar operation, distinguishing it from the unipolar-only LTC2641. The 14-bit resolution offers a balance between precision and speed, suitable for applications where 16-bit performance is excessive but 12-bit is insufficient.

Replacement Considerations

Public confirmed substitute part numbers are not provided in the source material. Verify compatibility with existing bipolar amplifier circuits if substituting with other bipolar DACs.

FAQ

What is the default DAC output state upon power-up?

The power-on reset circuit sets the LTC2642 DAC output to midscale.

How does the CLR pin affect the LTC2642 output?

A logic low on the CLR pin asynchronously clears the DAC output to midscale.

What is the minimum load resistance for unbuffered operation?

The VOUT pin can drive medium loads greater than 60kΩ without degrading INL or DNL.