The AD660 DACPORT® is a complete 16-bit, monolithic digital-to-analog converter with an on-chip reference, double-buffered latches, and an output amplifier. Fabricated using Analog Devices' BiMOS II process, it enables high precision bipolar linear circuitry with low power CMOS logic functions on the same chip.
The AD660 architecture ensures that 15-bit monotonicity does not change with time and temperature. Both integral and differential nonlinearity errors are maintained at ±0.003% (maximum). The on-chip output amplifier enables the voltage output to be accurate within 1/2 LSB (full-scale step) at 10 μs.
The AD660 has an extremely flexible digital interface. Data can be loaded into the AD660 in serial mode or dual 8-byte format. This is achieved through two digital input pins with dual functionality. The serial mode input format is pin-selectable and can be MSB-preferred or LSB-preferred. The serial output pin allows the user to daisy-chain several AD660 devices: shifting the data through the input latch to the next DAC, minimizing the number of control lines required to connect the SIN, CS, and LDAC. The byte-mode input format is also flexible, with the option to load high-byte or low-byte data first. The double-buffered latch architecture eliminates data skew errors and enables simultaneous updates of each DAC in a multiDAC system.
The AD660 is divided into five stages. The AN and BN grades are specified over the −40°C to +85°C temperature range and are available in a 24-lead, 300 mil plastic DIP package. The AR and BR grades are also specified over the −40°C to +85°C temperature range and are available in a 24-pin SOIC package. The SQ grade is available in a 24-pin 300 mil CERDIP package and is also available in MIL-STD-883 compliant versions. Refer to the AD660SQ/883B military grade data sheet for specifications and test conditions.
Product features
1. The AD660 is a complete 16-bit monolithic DAC with a voltage reference, double-buffered latches, and an output amplifier.
2. The internal embedded Zener reference is laser-trimmed to 10.000 V with a maximum error of ±0.1% and a temperature drift performance of ±15 ppm/°C. This reference can be used in external applications.
3. The output range of the AD660 is pin programmable and can be set to a 0 V to 10 V unipolar output range or a −10 V to +10 V bipolar output range. No external components are required.
4. The AD660 offers both dc and ac characteristics. DC characteristics include ±1 LSB integral nonlinearity (INL) error and ±1 LSB differential nonlinearity (DNL) error. AC characteristics include 0.009% THD+N and 83 dB signal-to-noise ratio (SNR).
5. The AD660's double-buffered latches not only eliminate data skew errors, but also enable simultaneous updates of each DAC in a multiDAC application.
6. Whether the DAC is in unipolar mode or bipolar mode, the clear function can asynchronously set the output to 0 V.
7. The output amplifier can achieve ±1/2 LSB accuracy in 10 μs in full-scale steps and 2.5 μs over temperature in 1 LSB step. When full-scale steps are loaded, the output glitch is typically 15 nV-s.