The iC-WG is an optoelectronic detector IC for linear and angle measuring systems, e.g. glass scales or rotary encoders. Monolithically integrated are photodiodes, amplifiers and comparators as well as TTL-compatible push-pull output drivers. All 14 tracks are differentially evaluated.
An integrated LED current control with driver stage makes it possible to directly connect a transmit LED with series resistor and also guarantees a constant optical received power. The setpoint for the receive current is adjusted via an external resistor. If the LED current control deviates from its working range, this is indicated at the error message output.
For the adjustment of a reticle the chip features two adjustment crosses and supplies the analog signals from three monitor photocurrent amplifiers. For exact radial alignment of the iC-WG (with reticle) to the code disk, two monitor photodiodes are arranged such that the track position can be checked (option, not available in the standard SMD package).
Two test pins permit a complete electrical functional test of the IC not including the photodiodes.
All push-pull and analog outputs are protected against ESD and short-circuits. The error message output NERR is also short-circuit-proof and due to it’s open-collector design bus capable.