CMX993 and CMX993W Standard and Wide Bandwidth Quadrature Modulators

Applications
APCO P25, wireless data
ISM transmitters
Digital TV/CATV modulators
Wireless LAN, Wireless Local Loop
IF or RF modulators
FSK, GMSK, 4FSK, C4FM
QPSK, QAM, SSB, OFDM, multi-carrier systems
SDR (Software Defined Radios)
WiMAX systems
OFDM/COFDM systems
Satellite communications
Cellular picocell/nanocell systems
RF channel bandwidths up to 100MHz

Description
The CMX993 and CMX993W are integrated, low voltage quadrature (I/Q) modulator ICs suitable for use in applications operating from 30MHz to 1000MHz. The devices integrate two matched double balanced mixers driven from a buffered and quadrature split local oscillator. The LO frequency is divided by either 2 or 4. The mixers form an I/Q vector modulator with programmable gain stages offering up to 30dB of gain, controlled in 2.5dB steps. Uncommitted low frequency differential amplifiers are provided for users to configure. These may be used to implement functions such as filtering, differential- to single-ended signal conversion and level shifting. The CMX993W product variant offers wide-bandwidth operation. A digital control interface, C-BUS, (an SPI compatible interface) allows gain control as well as power management of individual internal blocks to optimise system performance. The C-BUS interface operates from its own supply domain enabling the device to be interfaced to different voltage baseband devices. The CMX993 and CMX993W devices are supplied in RF optimised VQFN packages.