AD2S1200

12-Bit R/D Converter with Reference Oscillator AD2S1200 FEATURES Complete monolithic R/D converter Parallel and serial 12-bit data ports System fault detection Absolute position and velocity outputs Differential inputs ±11 arc minutes of accuracy 1,000 rps maximum tracking rate, 12-bit resolution Incremental encoder emulation (1,024 pulses/rev) Programmable sinusoidal oscillator on-board Compatible with DSP and SPI® interface standards 204.8 kHz square wave output Single-supply operation (5.00 V ± 5%) −40°C to +125°C temperature rating 44-lead LQFP package 4 kV ESD protection GENERAL DESCRIPTION The AD2S1200 is a complete 12-bit resolution tracking resolverto-digital converter, integrating an on-board programmable sinusoidal oscillator that provides sine wave excitation for resolvers. An external 8.192 MHz crystal is required to provide a precision time reference. This clock is internally divided to generate a 4.096 MHz clock to drive all the peripherals. The converter accepts 3.6 V p-p ± 10% input signals, in the range of 10 kHz to 20 kHz on the Sin and Cos inputs. A Type II servo 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 bandwidth of the converter is set internally to 1.7 kHz with an external 8.192 MHz crystal. The maximum tracking rate is 1,000 rps. FUNCTIONAL BLOCK DIAGRAM REFBYP REFOUT FS1 FS2 CLKIN XTALOUT (8.192MHz) AD2S1200 EXC EXC VOLTAGE REFERENCE REFERENC...