Based on a couple of the replies, I think I need to be clearer on what my problems are:-

I've got a Gameboy Camera which has a resolution of 128x123 the analog output is from this 0v = black and 2v = white.

There is a clock line on the camera, each time I pulse it, it updates the analog output line with the new pixel value.

Now, 128x123 is 15744 pixels, an A2D (i.e. ADC0804 ) can only do 8770 conversions/sec which means I get less than 1fps. So I ned something alot quicker.

I'm using AT89C52 chips running at 12Mhz, these give me around 1 Mip, but they only have 256 bytes of RAM, so space is limited, I can't even store a single frame in memory, so I want to bypass the need for this and have a logic 1 for ~1.8v otherwise I want it low.


I was thinking I could use a 3906 transistor, if I supply +5 to the collector, ground the emitter and put the analog output onto the base it should act like a switch?

I think this would work, but I'm no electronics genuis I know I need a resistor somewhere and to tap my I/O line on the emitter or collector, but I'm not sure which one.


Would this work? or am I completely wrong here?


Many thanks for all your helpful replies already :-)

Chris.