Spectrian Wins Patent for Bias Control ASIC

Spectrian Corp. has been granted a US Patent for the design of a temperature-compensating RF bias controller for wireless power amplifier. The BiASIC application-specific IC (ASIC) is designed to control bipolar devices by performing control functions in thermally sensitive RF power circuits.

The BiASIC design is based on Spectrian's discovery that accurate dynamic control of DC bias in the power transistor is a means to improve linearity in a power amplifier. To dynamically control DC bias, Spectrian's BiASIC features an internal thermal sensor and an optional input for thermal referencing. The patented ASIC also sports an additional modulation input to further customize the dynamic bias condition for improved linearity.

The BiASIC controller is internally and externally programmable to adjust for the varying transistor sizes and applications as well as for normal lot-to-lot variation in current gain. The BiASIC controller is also designed to reduce printed circuit board (PCB) space in power amp designs.

Spectrian sees several possible implementations of the BiASIC including: applications where the IC would be packaged separately in a surface-mount compatible package that can be installed on the PCB; applications where the IC is included in the power transistor package with external leads for in-circuit programming; and specific transistor applications where the bias controller is integrated onto the power transistor die, programmed internally during semiconductor test, and provided as part of a self-biased transistor.