A bilateral zener diode is described having improved terminal characteristics including a low noise factor, a predictable breakdown voltage level in the reverse breakdown mode within plus or minus 3 percent, and providing a sharp reference voltage which is substantially independent of diode current. This bilateral conducting diode is achieved by utilizing a collector ring diffusion of the same conductivity type as the anode diffusion, but spaced from both the anode diffusion and the cathode diffusion. In the forward bias conduction mode, the flow of current from the anode to the cathode is collected by the collector ring and returned to the cathode providing a forward transfer efficiency which is typically 90 percent.

Current scaling in a lateral transistor wherein a plurality of emitter-collector circuits are established, certain of said circuits having a different base width than certain other of said circuits. In one embodiment, separate transistors are formed, each with its own emitter and collector, each portion of each collector being spaced an equal distance from its associated emitter the base widths of the different transistors being different, such that, with the emitters coupled in common, different currents being dependent on the base width of the associated transistor. In a second embodiment, a common emitter is employed with the separate collectors formed as arcs about the emitter, the base widths between the emitter and the different collectors being different.

A capacitance multiplier circuit is disclosed which is fabricated using integrated circuit techniques comprising an inverted multiple collector transistor structure wherein a first one of the multiple collectors is electrically shorted to the base of the transistor to form a current mirror. The collector areas between the first collector and a second one of the multiple collectors are area ratioed to provide a multiplication factor, which is determined by the ratio between the areas of the two collector regions. The capacitance value formed between the junction of the base and the second collector regions is multiplied by this multiplication factor to produce an effective capacitance at the second collector. The multiplication factor is independent to process and temperature variations.

This invention relates to an integrated zener diode having a breakdown voltage of less than about 5 volts. In order to achieve predetermined breakdown voltages within a small gap in the mass production independent of the bulk resistivity fluctuations, the zener diode of the invention comprises a forward-biased control transistor, the base zone of which is fed via a resistor zone to the emitter of said transistor as well as via the collector-emitter-line of a further multi-emitter transistor structure to the collector of said control transistor.

A current mirror circuit wherein an I.sup.2 L circuit is employed as the load of a current mirror circuit formed of a PNP (NPN) transistor, the injector of the I.sup.2 L circuit is common with those of another group of I.sup.2 L circuits, and a predetermined current is derived from the PNP (NPN) transistor of the current mirror circuit.