1 Features
• Buried zener core 7.6V output
• Industry standard fixed output voltage
– 1X gain: 2.5V, 4.096V, 5V
– 2X gain: 5V, 8.192V, 10V
• No external buffer for 1X and 2X gain output
• Industry standard fixed output initial accuracy
– 1X gain: ±0.05%
– 2X gain: ±0.1%
• Ultra-low temperature drift: 0.05ppm/°C
• Operating temperature range: 0°C to 70°C
• Excellent long term stability: 0.3ppm (1khr to 5khr)
• 1/f noise (0.1Hz to 10Hz) : 0.15ppmpk-pk
• Integrated heater with temperature stable indicator
• Input Voltage range: 10V to 16.5V
• Heater supply range: 10V to 42V
• Hermetically sealed ceramic package (20 pin
LCCC)

2 Applications
• Parametric measurement unit
• Lab and field instrumentation
• Precision weight scales
• Battery test equipment
• Digital multimeter
• Source measurement unit
• Data acquisition

3 Description
The REF81 device utilizes precision buried zener
core with integrated heater to generate stable
7.6V. The device further integrates precision resistor
dividers and a buffer to offer industry standard
voltage references to drive precision data converters.
Integrated temperature control with an internal
heater enables the reference voltage stay constant
irrespective of ambient temperature variations
and achieve extremely low temperature drift of
0.05ppm/°C. The integration of control loop, precision
resistances and buffer enables ease of design and
eliminates need of external precision components.
The REF81 family is available in a 20-pin LCCC
package. The LCCC package is a hermetically
sealed ceramic package that enables ultra low
long-term stability specification of 1ppm, critical for
applications that demand a longer operational window
without calibration. The package also offers excellent
immunity against humidity variation.