REF7040QFKHT

Overview

The REF7040QFKHT is a high-precision series voltage reference from the Texas Instruments REF70 family, featuring a fixed output of 4.096 V in an 8-pin LCCC ceramic package. It delivers ±0.025% initial accuracy and a maximum temperature coefficient of 2 ppm/°C across a -40°C to +125°C range. The device exhibits ultra-low noise (0.23 ppmp-p at 0.1 Hz to 10 Hz) and supports bidirectional output currents up to ±10 mA with a dropout voltage as low as 400 mV. It operates on input voltages up to 18 V and includes a shutdown feature for power management.

Feature Summary

• Hermetically sealed LCCC ceramic package ensures humidity resistance and long-term stability without calibration.
• Ultra-low noise performance enables precision measurements in sensitive analog front ends.
• Integrated enable pin allows for effective power management through a dedicated shutdown mode.

Applications

• Semiconductor test equipment
• Precision data acquisition systems
• Ultrasound scanners
• X-ray systems

Procurement Notes

Verify the specific suffix 'QFKHT' corresponds to the hermetic LCCC package variant when sourcing. Confirm that the required output voltage matches the fixed 4.096 V specification. Ensure the application environment stays within the specified -40°C to +125°C operating temperature range. Check datasheet requirements for stable output capacitors between 1 μF and 100 μF.

Selection Notes

Select this component for applications requiring hermetic sealing and minimal long-term drift over extended periods. The 4.096 V output is suitable for interfacing with high-resolution ADCs and DACs. Consider the LCCC package size constraints and thermal characteristics compared to plastic alternatives like VSSOP if environmental sealing is not required.

Part Context

The REF7040QFKHT belongs to the REF70 family of ultra-high-precision voltage references designed for demanding industrial and medical applications. This family offers industry-leading noise and drift specifications. The QFKHT designation specifically identifies the hermetic ceramic package version, distinguishing it from standard plastic packages within the same electrical family.

Replacement Considerations

REF7040QDGKR

FAQ

What is the function of the EN pin?

The EN pin controls the device state. Driving it below 0.5 V disables the reference output and enters shutdown mode, while driving it above 1.6 V enables normal operation.

How does the LCCC package benefit long-term stability?

The hermetically sealed ceramic LCCC package protects the internal circuitry from humidity and contaminants, ensuring excellent long-term stability (35 ppm over 1k hours) without requiring recalibration.