I need an IR receiver that can directly be used with a microprocessor - the TSOP series from Vishay seems to fit well and there are enough tutorials and software libraries to make use of it. Unfortunately in my design I only have space for a normal 3mm (preferably) or 5mm LED receiver diode. Is there a simple IR driver chip that works like the TSOP receivers but with an external IR diode? So it should have 4 pins (Vs, OUT, GND, LED-INPUT) instead of 3 pins, three of them (Vs, OUT, GND) to be used as IR receivers with build-in IR diode and the fourth to connect the diode to (and to GND, of course).
P.S: Maybe a bit more background about my actual project: I want to put an IR receivers into a LEGO® and/or DUPLO® bricks, such as shown in this project. The bricks shall receive signals such as "brick number 12, switch on", "brick number 7, send temperature" etc. from a TV remote control, from an IR keyboard and/or from a custom IR sender at the ceiling. There is enough space at least in a DUPLO brick for one or two additional microprocessors (e.g. ATtiny 13/45/85) and a few wires and resistors. The only possible solution I found so far is using transparent bricks.