This is a Tibbit module — part of the Tibbo Project System that allows you to build your own custom embedded device with only the components you need. Start with a Tibbo Project PCB, add Tibbits like this one, then place the built design into a Tibbo Project Box to complete your product.
Tibbit #04_1: Two optically isolated inputs with independent terminals. Inputs are fully isolated from system ground.
If no external resistor is added, these inputs activate at about 2V. Forward current should not exceed 10mA; this caps the maximum input voltage at around 5V. Add external resistors if you need to apply higher input voltage.
Combine this Tibbit with a terminal block C Tibbit #20 (nine terminal blocks) or #21 (four terminal blocks).
There are two green LEDs each of which is connected to a control line. They light up for the LOW state (i.e. when current passes through the diodes of the opto-couplers).
M1S Tibbit Modules Overview M1S Tibbits are single-width modules occupying one standard M socket on a Tibbo Project PCB (i.e. TPP2 or TPP3). Their footprint is roughly 7 × 14 "squares" (one "square" is 2.54 × 2.54 mm). The M1S modules are 12.5mm high.
M1 modules have two rows of 6 pins:
Pins 8-11 are control lines A-D. They provide the interface to programmable modules or other microcontrollers. On Tibbo Project PCBs, these pins are connected to the main processor.
Pins 2-5 are I/O lines facing the outside world. On Tibbo Project PCBs, they go to C Tibbits.
Pins 6 and 12 are the GROUND and +5V power pins. Most Tibbit Modules consume (take) 5V power. There are also power supply Tibbits that generate 5V power from a variety of sources. Those output 5V through pin 12.
Pins 1 and 7 are for the additional +15V and -15V voltages. These are optional and only needed by few Tibbits. A special power supply Tibbit (#12) generates ±15V from the main 5V power.