AD2S1205:  12-Bit R/D Converter with Reference Oscillator

The AD2S1205 is a complete 12-bit resolution tracking resolver-to-digital converter that contains an on-board programmable sinusoidal oscillator providing sine wave excitation for resolvers.

The converter accepts 3.15 V p-p ± 27% input signals on the Sin and Cos inputs. A Type II tracking loop is employed to track the inputs and convert the input Sin and Cos information into a digital representation of the input angle and velocity. The maximum tracking rate is a function of the external clock frequency. The performance of the AD2S105 is specified across a frequency range of 8.192 MHz ± 25%, allowing a maximum tracking rate of 1250 rps.

Product Highlights

1. Ratiometric Tracking Conversion. The Type II tracking loop provides continuous output position data without conversion delay. It also provides noise immunity and tolerance of harmonic distortion on the reference and input signals.
2. System Fault Detection. A fault detection circuit can sense loss of resolver signals, out-of-range input signals, input signal mismatch, or loss of position tracking.
3. Input Signal Range. The Sin and Cos inputs can accept differential input voltages of 3.15 V p-p ± 27%.
4. Programmable Excitation Frequency. Excitation frequency is easily programmable to 10 kHz, 12 kHz, 15 kHz, or 20 kHz by using the frequency select pins (the FS1 and FS2 pins).
5. Triple Format Position Data. Absolute 12-bit angular position data is accessed via either a 12-bit parallel port or a 3-wire serial interface. Incremental encoder emulation is in standard A-quad-B format with direction output available.
6. Digital Velocity Output. 12-bit signed digital velocity accessed via either a 12-bit parallel port or a 3-wire serial interface.

Applications

Data Sheet, Rev. 0, 1/07