Disclosed is a memory array structure, where a wordline driver selectively applies a high on-state voltage (VWLH) or a low off-state voltage (VWLL) to a wordline. VWLH has a slightly negative temperature coefficient so that it is regulated as high as the gate dielectric reliability limits allow, whereas VWLL has a substantially neutral temperature coefficient. To accomplish this, the wordline driver is coupled to one or more voltage regulation circuits. In one embodiment, the wordline driver is coupled to a single voltage regulation circuit, which incorporates a single voltage reference circuit having a single output stage that outputs multiple reference voltages. Also disclosed is a voltage reference circuit, which can be incorporated into the voltage regulation circuit of a memory array structure, as described, or, alternatively, into any other integrated circuit structure requiring voltages with different temperature coefficients. Also disclosed is a method of operating a memory array structure.