LTC2666CUH-16#TRPBF

Overview

The LTC2666CUH-16#TRPBF is an octal, 16-bit digital-to-analog converter (DAC) featuring SoftSpan technology and a ±10V output capability. It integrates a precision reference with a maximum temperature coefficient of 10ppm/°C. The device provides eight independent channels with rail-to-rail buffered outputs capable of driving ±10mA. Each channel supports independently programmable output ranges: 0V to 5V, 0V to 10V, ±2.5V, ±5V, or ±10V. It utilizes a 3-wire SPI/Microwire-compatible serial interface operating at clock rates up to 50MHz with logic levels as low as 1.71V. The component includes A/B toggle registers, an 8:1 analog multiplexer, and thermal protection.

Feature Summary

• Octal 16-bit resolution with integrated 2.5V precision reference (max 10ppm/°C).
• SoftSpan™ technology allowing independent programming of five output ranges per channel.
• Built-in rail-to-rail output buffers driving ±10mA load current.
• 3-wire SPI/Microwire interface compatible with 1.71V logic levels.

Applications

• Optical networking systems
• Precision instrumentation
• Data acquisition systems
• Automatic test equipment
• Process control and industrial automation

Procurement Notes

Verify the #TR suffix indicates a tape and reel packaging configuration containing 2500 pieces. Confirm the C grade designation corresponds to the commercial operating temperature range of 0°C to 70°C. Ensure the UH package type matches the required 32-lead QFN footprint for the target PCB layout.

Selection Notes

Select this part for applications requiring multiple high-resolution voltage outputs with flexible range configurations. The internal reference simplifies design by eliminating external components for standard spans. Consider the ±10V supply requirement for bipolar ranges; single-supply operation is possible only for unipolar ranges when V– is tied to ground.

Part Context

This component belongs to the LTC2666 family of SoftSpan DACs. The CUH-16 suffix specifies the 16-bit resolution variant in the commercial temperature grade housed in a 32-lead QFN package. The TRPBF suffix denotes the tape and reel packaging format with lead-free finish.

Replacement Considerations

LTC2666CUH-16#PBF is the tube-packaged equivalent of this component. Other members of the LTC2666 family offer different resolutions or temperature grades but share the same pinout and functionality.

FAQ

How are the output ranges configured?

Each of the eight channels can be independently programmed via software to one of five ranges: 0V to 5V, 0V to 10V, ±2.5V, ±5V, or ±10V. Alternatively, hardware pins (MSP0, MSP1, MSP2) can fix the power-on span.

What is the function of the TGP pin?

The TGP (Toggle Pin) allows asynchronous switching between Register A and Register B data. A falling edge updates the DAC from Register A, while a rising edge updates it from Register B, provided the specific channel's toggle select bit is enabled.

Can the negative supply V– be connected to ground?

Yes, the V– supply can be tied to ground for unipolar operation (e.g., 0V to 5V or 0V to 10V ranges). However, bipolar ranges require a negative supply voltage between –4.5V and –15.75V.