i do can build something like FTDS45000
the schematic is
http://www.microchip.com/download/...51246a.pdf
page 55
in the development board you can use the FTDS45000 OR with some IC's you can make the same function of FTDS45000

LM393 Low Power Low Offset Voltage Dual Comparator
MCP601 operational amplifier

there is also MAX3120 which is only needs the IR LEDS but i want the hole thing in one packet and be able to solder
has anybody been through this?