MAX5121BEEE

Overview

The MAX5121BEEE is a low-power, 12-bit voltage-output digital-to-analog converter (DAC) from Analog Devices/Maxim Integrated. Operating on a +3V supply, it delivers a full-scale output range of +2.0475V using an internal precision bandgap reference of +1.25V. The device draws 500µA in normal operation and reduces to 3µA in power-down mode. It features a buffered output capable of driving 5kΩ loads with a settling time of 20µs. The serial interface supports SPI, QSPI, and MICROWIRE protocols. Accuracy specifications include ±2 LSB INL and ±1 LSB DNL for the B-grade variant.

Feature Summary

• 12-bit resolution with ±2 LSB INL and ±1 LSB DNL
• +3V single-supply operation with +2.0475V full-scale output
• Internal 1.25V precision bandgap reference (<10ppm/°C)
• 3-wire serial interface compatible with SPI/QSPI/MICROWIRE
• Power-down current reduced to 3µA

Applications

• Industrial Process Controls
• Automatic Test Equipment (ATE)
• Digital Offset and Gain Adjustment
• Motion Control Systems
• Microprocessor-Controlled Systems

Procurement Notes

Verify the specific grade suffix 'B' corresponds to the required accuracy levels (±2 LSB INL, ±1 LSB DNL). Confirm the package type is 16-pin QSOP. Check for RoHS compliance status as indicated in official documentation. Ensure availability matches current manufacturing status, as older Maxim products may have limited stock or end-of-life considerations.

Selection Notes

Select the MAX5121BEEE when a +3V supply is available and a +2.0475V output swing is sufficient. Choose this part over the MAX5120 if lower voltage operation is required. Consider the B-grade accuracy if tighter linearity than the A-grade (±1 LSB INL) is not necessary. Verify that the 20µs settling time meets system speed requirements.

Part Context

The MAX5121 is part of the MAX5120/MAX5121 family of 12-bit serial DACs. It shares pinout and functionality with the MAX5120 but operates at +3V instead of +5V. Pin-compatible upgrades are available in 13-bit (MAX5130/MAX5131) and 14-bit (MAX5170/MAX5172) resolutions. The B-grade variant offers slightly relaxed linearity specifications compared to the A-grade version.

Replacement Considerations

For pin-compatible upgrades, consider the MAX5131 (13-bit) or MAX5172 (14-bit). Direct functional replacements within the same voltage class include the MAX5121AEEE for higher accuracy. Ensure any substitute maintains compatibility with the 3-wire serial interface and QSOP package.

FAQ

How is the internal reference disabled for external reference use?

Pull the REFADJ pin to VDD to disable the internal reference. Apply the external reference signal to the REF pin.

What is the maximum serial clock frequency for the MAX5121?

The maximum guaranteed serial clock frequency is 6.6MHz for the MAX5121.

Can the output offset be adjusted?

Yes, the OS pin allows for adjustable output offset. Applying a voltage to the OS pin shifts the DC output level.