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In a GaAs integrated circuit, a voltage reference generator includes a pair of Schottky diodes and a first, current-source connected, depletion-mode MESFET coupled in series to conduct current from a ground node to a voltage supply node. The current-source connected FET causes a constant current to

In a GaAs integrated circuit, a voltage reference generator includes a pair of Schottky diodes and a first, current-source connected, depletion-mode MESFET coupled in series to conduct current from a ground node to a voltage supply node. The current-source connected FET causes a constant current to flow from the ground node through the diodes, producing a constant voltage drop which generates a constant reference voltage at a reference node between the diodes and FET. A second pair of Schottky diodes is connected in series between the source of the FET and the voltage supply node, in a loop coupling the source to the gate of the FET, to provide a voltage difference Vgs across the FET proportional to voltage drop across the second pair of diodes. This voltage difference varies with fabrication process and temperature variations and causes the first FET to modify the amount of current flow to compensate so as to maintain a constant voltage drop across the first pair of diodes. A second FET is connected between the reference node and the first, current-source connected FET and has its gate coupled to the source of the first FET, either directly or through one of the second pair of diodes. Any variations in supply voltage are transmitted to the drain of the first FET to maintain a constant voltage Vds and current Ids, thereby stabilizing the reference voltage against supply voltage variations and noise.

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In a GaAs integrated circuit, a GaAs voltage reference generator comprising: a first diode means connected to conduct current from a nominal ground node to a voltage reference node; a depletion-mode FET connected in series with the first diode means, the FET having a gate, a drain coupled to the ref

In a GaAs integrated circuit, a GaAs voltage reference generator comprising: a first diode means connected to conduct current from a nominal ground node to a voltage reference node; a depletion-mode FET connected in series with the first diode means, the FET having a gate, a drain coupled to the reference node and a source coupled to a voltage supply node; conductor means coupling the gate of the FET to the voltage supply node for current-source connecting the FET to cause a current to flow between the ground node and the voltage supply node, the current being substantially constant for a constant voltage difference between the gate and source of the FET and a constant operating temperature of the integrated circuit; and a second diode means connected to conduct current from the source of the FET to the voltage supply node; each of the diode means being operative to produce a voltage drop which varies within a predetermined range as a function of at least one of integrated circuit temperature and fabrication process variations; the second diode means being coupled in a loop including the FET and the conductor means for determining and varying said voltage difference proportionally to the voltage drop of the second diode means; the current-source connected FET being responsive to a variation in said voltage difference to vary said current so as to compensate for a variation in voltage drop across the diode means due to temperature or process variations and thereby provide a predetermined voltage at the voltage reference node that remains constant for a constant supply voltage.