LM399A

~National ~ Semiconductor Voltage References and Regulators LM199A1LM299A1LM399A Precision Reference General Description The LM 199A/LM299A/LM399A are precision, temperature-stabilized monolithic zeners offering temperature coefficients a factor of ten better than high qual ity 'reference zeners, Constructed on a single monolithic chip is a temperature stabilizer circuit and an active reference zener, The active circuitry reduces the dynamic impedance of the zener to about 0.5S1 and allows the zener to operate over 0.5 mA to 10 mA current range with essentially no change in voltage or temperature coefficient. Further, a new subsurface zener structure gives low noise and excellent long term stability compared to ordinary monolithic zeners. The package is supplied with a thermal shield to minimize heater power and improve temperature regulation. The LM 199A series references are exceptionally easy to use and free of the problems that are often experienced with ordinary zeners. There i...