LM129

The LM129 and LM329 family are precision multi-current temperature-compensated 6.9V zener references with dy- namic impedances a factor of 10 to 100 less than discrete di- odes. Constructed in a single silicon chip, the LM129 uses active circuitry to buffer the internal zener allowing the de- vice to operate over a 0.5 mA to 15 mA range with virtually no change in performance. The LM129 and LM329 are avail- able with selected temperature coefficients of 0.001, 0.002, 0.005 and 0.01%/˚C. These references also have excellent long term stability and low noise.

A new subsurface breakdown zener used in the LM129 gives lower noise and better long-term stability than conventional IC zeners. Further the zener and temperature compensating transistor are made by a planar process so they are immune to problems that plague ordinary zeners. For example, there is virtually no voltage shift in zener voltage due to tempera- ture cycling and the device is insensitive to stress on the leads.