Lowest-drift bandgap voltage reference reaches 1.5ppm/°C, offers low dropout

October 19, 2015 // By Graham Prophet
LT6657 is a family of ultra-stable bandgap voltage references that exhibits less than 1.5ppm/°C of temperature drift. Reinforcing this performance, the device has only 0.5ppm p-p of low frequency noise, less than 30 ppm of long term drift and 35 ppm of thermal hysteresis.

The LT6657 is fully specified for –40°C to 125°C and was designed for the most demanding high performance instrumentation, test equipment and automotive systems. The LT6657’s buffered output can source and sink up to 10 mA. The LT6657 can operate on a supply voltage from as low as 50 mV above the output, up to 40V, and with a supply current of only 1.2 mA. In shutdown mode, power consumption is reduced to 4 µA. Load regulation error is less than 6 ppm/mA and line regulation error is less than 4 ppm/V, both under worst case conditions.

Linear emphasises that this reference is “low-dropout” and can operate to within 50 mV of the output, where as other devices offering comparable stability are buried-Zener-based rather than bandgap, and need elevated supply voltages. This, linear says, can save power drain and remove the need for a separate supply line.

“With its outstanding precision and noise, the LT6657 sets a new high water mark for bandgap references,” says Brendan Whelan, Design Manager for Linear Technology. “There is now a low dropout, small and adaptable voltage reference option with enough precision for the next generation of ultra-precision electronics.”

The LT6657 is currently in production with a 2.5V output version. Additional voltage options are in development. Prices start at $3.19 (1,000)

Linear Technology; www.linear.com/product/LT6657