January 10, 2012 – Linear Technology Korea (CEO Hong Sa-gwak) announced the launch of the industry's first high-performance dual 18-bit current output DAC (digital-to-analog converter) new product (product name: LTC2758). The LTC2758 delivers precision 18-bit DC specifications including ±1LSB (max) INL and DNL over a specified temperature range. Beyond excellent DC specifications, the LTC2758 offers fast settling time of 2.1µs and low glitch impulse of 0.4nV•s (3V), 2nV•s (5V), enabling generation of high-frequency, low-noise output waveforms. As these DC and AC accuracy characteristics are combined in the dual DAC, higher-performance designs for medical devices, measuring instruments, automated test equipment, process control, and industrial automation become possible.
The LTC2758's SoftSpan™ feature can output six unique unipolar and bipolar output ranges up to ±10V. The output voltage range includes two selectable unipolar ranges (0V ~ 5V, 0V ~ 10V) and four bipolar ranges (±10V, ±5V, ±2.5V, -2.5V ~ +7.5V) that can be selected using software or pin-strapping. The LTC2758 also integrates precision resistors for each DAC for reference inversion, bipolar offset, and gain/offset adjustment. Therefore, expensive external precision resistors and gain stages are not required, allowing customers to improve production logistics and quickly manage and process inventory mix adjustments.
The LTC2758 communicates through a 3-wire bidirectional input/output SPI serial interface, enabling readback of DAC output span settings as well as any internal registers. Through voltage-controlled offset and gain adjustment pins, users can eliminate system offset, gain error, or reference error.
The LTC2758 belongs to the previously released pin/software-compatible 16-bit dual IOUT DAC LTC2752 product line. The DC1684A is the associated demo board for evaluating the LTC2758 and LTC2752.
The LTC2758 is offered in a 7mm x 7mm LQFP-48 package, with product pricing starting at $27.91 per unit based on 1,000-unit quantities. For detailed product information, refer to www.linear.com/product/LTC2758.

Photo caption: Dual 18-Bit IOUT DAC

Product Features: LTC2758

• Maximum 18-bit INL error: ±1LSB over specified temperature range
• Six output ranges programmable or pin-strappable:
0V ~ 5V, 0V ~ 10V, –2.5V ~ 7.5V, ±2.5V, ±5V, ±10V
• Monotonicity guaranteed over specified temperature range
• Glitch impulse 0.4nV•s (3V), 2nV•s (5V)
• 18-bit settling time: 2.1μs
• Single supply operation 2.7V ~ 5.5V
• Maximum supply current 1μA
• Voltage-controlled offset and gain trimming
• Serial interface with all registers readable (readback)
• Clear/power-on reset to 0V regardless of output range
• 48-pin 7mm × 7mm LQFP package