Asahi Kasei Microdevices Corporation, (AKM), has started mass production of the AK2403, a narrow band radio transceiver IC. The AK2403 achieves high linearity which is required for the QPSK and QAM modulation methods using Cartesian Feedback Loop technology. Since the AK2403 integrates a DAC and PLL circuits, it contributes to size reduction of the transmission block in professional digital mobile radios.
In addition, AKM has started mass production of the AK2401A, a new direct conversion transmitting/receiving IC. It uses a simple PSK radio system that was normally composed from many discrete parts with a combination of a transmission IC, the AK2403.
- Integrated D/A Converter and PLL:
Digital signals from a digital baseband IC can be directly received since the AK2403 integrates DACs. The output range of the DAC can be adjusted by 1 dB steps with a range from –8 dB to 7 dB and it can be adjusted by 0.1 dB step from 0 dB to 1.5 dB. The internal PLL covers LO frequency from 50 MHz to 1.0 GHz with a Fractional-N synthesizer. An internal or an external VCO can be used with the internal PLL. Low phase noise can be realized with the internal VCO.
- Easily achieved DC offset calibration:
The AK2403 has a DC offset calibration function that detects the DC offset from the full differential amplifier output and cancels it. DC offset calibration can be executed easily just by writing “1” to the register setting.
- Great Wideband Noise (WBN) Characteristics:
The AK2403 achieves –105 dBc WBN characteristics with enough margins to cover the most difficult standard value of –100 dBc, which is TETRA standard’s WBN with 5 MHz offset. (Measurement Conditions: 400 MHz Frequency, 3 W Output)