DAC8408FS-REEL Analog Devices Inc, DAC8408FS-REEL Datasheet - Page 14

• Manufacturer Part Number: DAC8408FS-REEL
• Manufacturer: Analog Devices Inc

Specifications of DAC8408FS-REEL

• Number Of Channels: 4
• Resolution: 8b
• Conversion Rate: 5.26MSPS
• Interface Type: Parallel
• Single Supply Voltage (typ): 5V
• Dual Supply Voltage (typ): Not RequiredV
• Settling Time: 0.25us
• Architecture: R-2R
• Power Supply Requirement: Single
• Output Type: Current
• Integral Nonlinearity Error: ±0.5LSB
• Single Supply Voltage (min): 4.5V
• Single Supply Voltage (max): 5.5V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 28
• Package Type: SOIC W
• Lead Free Status / Rohs Status: Not Compliant

DAC8408
A LOW-DISTORTION, PROGRAMMABLE
SINEWAVE OSCILLATOR
By varying the previous state-variable filter topology slightly,
one can obtain a very low distortion sinewave oscillator with
programmable frequency feature as shown in Figure 11. Again,
DAC B and DAC D in tandem control the oscillating frequency
based on the relationship f
accomplished via the 82.5 k and the 20 k potentiometer.
The Q of the oscillator is determined by the ratio of 10 k and
Figure 11. A Digitally Programmable, Low-Distortion Sinewave Oscillator
C
= 1/2 RC. Positive feedback is
–14–
475 in series with the FET transistor, which acts as an auto-
matic gain control variable resistor. The AGC action maintains
a very stable sinewave amplitude at any frequency. Again, only
two ICs accomplish a very useful function.
At the highest frequency setting, the harmonic distortion level
measures 0.016%. As the frequencies drop, distortion also drops
to a low of 0.006%. At the lowest frequency setting, distortion
came back up to a worst case of 0.035%.
REV. A