Maxim Integrated Products introduces the AX11014/MAX11015 ICs that set and control bias conditions for dual MESFET power devices found in point-to-point communication and other microwave base stations. The MAX11014 integrates closed-loop drain-current control for class A MESFET amplifier operation, while the MAX11015 sets the MESFET gate voltage for class AB operation. Both devices integrate SRAM look-up tables (LUTs) that can be used to store temperature and drain-current compensation data. Each device includes dual, high-side, current-sense amplifiers to monitor the MESFET drain currents through the voltage drop across the sense resistors in the 0 to 625 mV range. External diode-connected transistors monitor the MESFET temperatures, while an internal temperature sensor measures the local die temperature. An internal DAC sets the voltages across the current-sense resistors by controlling the gate voltages. The internal 12-bit SAR ADC digitizes internal and external temperature, internal DAC voltages, current-sense amplifier voltages and external gate voltages. Two of the eleven ADC channels are available as general-purpose analog inputs for analog system monitoring. An internal reference provides a well-regulated, low-noise, +2.5 V reference for the ADC, DAC and temperature sensors, while still allowing the flexibility to operate from the ADC’s and DAC’s individual external references.
Maxim Integrated Products