Analog Devices’ quad-channel, 2.4-Gsample/sec, 16-bit D/A converter offers leading dynamic range performance in the 100- to 300-MHz band for complex IF transmitters. The highly integrated AD9154 quad, 16-bit D/A converter is the only device of its kind to include an on-chip PLL (phase-locked loop) and eight-lane JESD204B interface. The combination of features allows designers to use a single device to meet all of their requirements in multicarrier GSM and LTE transmitters designed for wireless macro base stations, point-to-point microwave radio, military radios and radio test equipment. The new converter includes a range of features optimised for complex IF (intermediate frequency) transmit applications, including complex digital modulation, input-signal power detection, and gain, phase and offset compensation.
The AD9154 is designed to up-convert a pair of I/Q digital input signals, creating a complex IF signal at the input to a pair of on-chip D/A converter cores. The new device features several interpolation modes, increasing the sampling rate of the digital signal to the Nyquist frequency to enable simpler, less costly transmitter filters following the D/A converter analogue output. The AD9154 includes digital-signal correction for quadrature modulator up-converters to cancel RF (radio frequency) local oscillator feed-through and unwanted side-bands.
The converter was designed with an eight-lane JESD204B interface that simplifies board layout by providing deterministic latency and multi-device synchronisation for radio transmitters that use multiple antennae.
The AD9154 quad, 16-bit D/A converters extends ADI’s transmit capabilities to the 100- to 300-MHz range, and joins the AD9144 quad, 16-bit D/A converter, which operates in the DC to 100-MHz range, and will be joined later in 2015 by a 16-bit dual-channel D/A converter.
Single-carrier LTE 20-MHz bandwidth ACLR = 76.7 dBC at 180-MHz IF
Six-carrier GSM IMD = 78-dBC, 600-kHz carrier spacing at 180-MHz IF
SFDR = 72-dBC at 180-MHz IF, -6 dBFS
8-lane JESD204B interface
Support for quad-DAC or dual-DAC mode
Low power: 2.1-W at 1.5 GSPS