Analog Devices, Inc. has released a low-power generation of its popular TxDAC transmit digital-to-analog converters (DACs). Optimized to the requirements of communications, industrial instrumentation and portable applications that require high-speed performance with the lowest power consumption, the AD970x family reduces power dissipation by up to 70% over previous DAC offerings. As a transmit-quality converter, the AD970x family is suited for applications that need to synthesize broadband signals efficiently--from handheld radios to portable instruments.

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In addition, the AD970x family integrates an on-chip voltage reference and Rset and Rload resistors, lowering component count and bill-of-materials costs. The devices also feature common mode shift capability, minimizing the need for level-shifting circuitry when interfacing with other analog components. This level of integration, the first of its kind for transmit path data converters, simplifies analog design and reduces printed circuit board area for smaller portable designs, said the manufacturer.

The AD970x family supports update rates at 175 mega samples per second (Msps) and comprises four products: the AD9707 14-bit DAC; and the AD9706, AD9705 and AD9704, which are 12-, 10-, and 8-bit DACs, respectively. The family features best-in-class spurious-free dynamic range (SFDR) of 86 dBc and intermodulation (IMD) of 70 to 50 MHz.

All of the devices share the same interface, small outline package and pin-out, providing an upward or downward component selection path based on performance, resolution and cost.

The AD9707 has a flexible power supply operating range from 1.7 V to 3.6 V. At 3.3 V, the AD970x family dissipates 35 mW of power and at 1.8 V dissipates 12 mW. Its power dissipation can be further reduced by 15 mW by lowering the full-scale current output. Sleep and power-down modes reduce dissipation to 5 mW for low-power idle periods.

The devices are available in 28-lead TSSOP (thin-shrink small-outline plastic package) and 32-lead LFCSP (lead-frame chip-scale package) packaging. The devices in the LFCSP packaging include an optional SPI (serial peripheral interface), which provides a higher level of programmability and an adjustable output common mode feature that enables the TxDAC to easily interface to other components that require common modes greater than 0 V. The AD9707 is also self-calibrating, allowing it to achieve greater accuracy and true 14-bit INL (integral nonlinearity) and DNL (differential nonlinearity) performance.

The AD970x family is sampling now with production quantities available in October 2005. Pricing for the family ranges from $2.75 to $5.75 in 1000-unit quantities, depending on resolution. The devices are supported by an evaluation board and two development tools: the high-speed DAC Pattern Generator (DPG), which provides digital data for ADI's DAC evaluation boards, and VisualDAC, an integrated development and debugging environment.