Multivibrator circuit used as a delay element.

摘要

The invention relates to a multivibrator circuit used as a delay element. The complementary signals to be delayed control the transistors (322,362) of a long tailed pair, so as to generate charging and discharging currents for a capacitance (38). The delay time depends among other parameters on the exact values of these currents. In order to avoid the necessity of very accurate values of the signals to be provided for generating the proper current values, a current division is applied, such that in parallel to each long tailed pair transistor (322,362) a constant current source (321,361) is added. Now the currents in the multivibrator circuit can be switched between two exactly determined values by alternately switching the long tailed pair transistors (322,362) fully on and off. A same kind of current division is applied in order to achieve the voltage swing at the output being independent on the current adjustment.