Apparatus and methods are provided for generating output signals representative of bits of serial data. A transmitter includes driver circuitry configured to generate an output signal at an output node and an allocation control module coupled to the driver circuitry. The driver circuitry includes a plurality of driver legs configured to generate the output signal based on a plurality of data bits. The allocation control module is configured to allocate a respective subset of the plurality of driver legs to a respective data bit of a plurality of data bits, wherein the each subset generates a component of the output signal that is influenced by its respective data bit.