February 13, 2013 – Linear Technology Korea (CEO Hong Sa-kwak) announced the launch of a closed precision voltage reference product series (product name: LS8) supplied in a 5mm x 5mm surface mount low-stress ceramic package. Precision voltage references provide excellent long-term stability and consistently predictable operation over extended periods of operation. For instruments requiring the highest possible performance over decades of operation, the LS8 package can serve as an alternative to large metal cans or ceramic DIP packages.

Mechanical stress on the internal die of the voltage reference causes output voltage fluctuations. The LS8 package achieves excellent stability and minimizes die stress in numerous ways. First, the LS8 is a sealed package that eliminates the effects of humidity. A significant yet little-known cause of failure is the absorption of moisture inside unsealed plastic packages. Generally, non-sealed components can experience 150 ppm or more with a 25% change in relative humidity.

Furthermore, the LS8 package has a minimal direct die contact surface, which reduces die stress from the package. In contrast, with plastic molding, stress is applied directly to the silicon die during overtime and overheating. Because silicon and plastic have different coefficients of thermal expansion, temperature cycling on plastic parts will apply inelastic stress to the die. The result is residual failure even when the part reaches 25°C. Similarly, long-term drift failures in large parts are attributed to the plastic package stabilization process in the event of overtime. All these errors are remarkably reduced in the LS8 reference family. “The LS8 package is an innovative product for voltage reference,” said Brendan Whelan, Design Manager at Linear Technology. “Its excellent characteristics regarding humidity impact, hysteresis, and long-term drift will minimize system compensation requirements. This is welcome news for precision equipment manufacturers.”

The LS8 reference family is based on Linear Technology's four most representative precision voltage reference products: the LTC6655, LTC6652, LT6654, and LT1236. These products include a 5V buried Zener reference and three low dropout, 2.5V bandgap references. These voltage references feature a temperature drift of 2 ppm/°C to 20 ppm/°C, operation from -40°C to 125°C, and low-frequency noise characteristics down to 0.25 ppm.

Linear Technology's LS8 reference is currently in production. For detailed information, please refer to www.linear.com/product/LTC6655 .

Product Features: LS8

• Sealed package unaffected by humidity
• Excellent thermal hysteresis performance
• Excellent long-term stability performance
• Consistent operation
• Low-profile, 5mm x 5mm surface-mount LS8 package
• LTC6655-2.5: 2.5V Precision Bandgap Reference
o Grade A 2 ppm/°C
o Grade B 5ppm/°C
o Industry-leading noise performance: < 625nVP-P
o 5ppm thermal hysteresis (0°C ~ 70°C)
o 20ppm/√kHr long-term stability
• LTC6652-2.5: 2.5V Precision Bandgap Reference
o Grade A 5ppm/°C
o Grade B 10ppm/°C
o 350μA power supply current with 2μA shutdown
o 8ppm thermal hysteresis (0°C ~ 70°C)
o 20ppm/√kHr long-term stability
• LT6654LS8-2.5: 2.5V Precision Bandgap Reference
o Grade A 10ppm/°C
o Grade B 20ppm/°C
o Power supply voltage at 100mV dropout, max 36V
o 3ppm thermal hysteresis (0°C ~ 70°C)
o 15ppm/√kHr long duration stability
• LT1236LS8-5: 5V Precision Embedded Zener Reference
o Grade A 5ppm/°C
o Grade B 10ppm/°C
o 0.6 ppmp-p noise (0.1 Hz ~ 10 Hz)
o 8ppm thermal hysteresis (0°C ~ 70°C)
o 20ppm/√kHr long-term stability