iC-LO is suitable for the assembly of diffuse reﬂective photoelectric sensors based on the principle of triangulation. Besides iC-LO, all that is required to create such a setup is a transmitting LED, a low-cost microcontroller, and a driver device for the switching output.
The iC contains a photodiode array, consisting of one near diode, 127 middle diodes, and one far diode.
The diode photocurrents are segmented on two AC ampliﬁers (near and far channel). The AC ampliﬁers ensures a very good suppression of low-frequency interference. The sum and difference are calculated from the output voltages of the ampliﬁers; these are evaluated by comparators. From the comparator signals a programmable ﬁlter for the evaluation of multiple measurements generates the switching signal for the light sensor and also a warning on weak received light. The gain characteristic is dynamically adjusted to the intensity of the received light and becomes a logarithmic characteristic with very powerful input signals (reﬂective objects). This results in a very high dynamic range. The integrated low sidedriver can drive an LED directly or control an external driver by CMOS output.
iC-LO is conﬁgured using an SPI interface. The in ternal registers can be protected against overwriting.