How about this (temp. compensated buffer):
Select fixed width font (terminal)

      VCC   VCC
      |     |
      |     R2
      C     |
IN---B      E---OUT
 NPN  E----B  PNP
      |     C
      R1    |
      |     |
      GND   GND

Voltage gain is about 1 works to within 0.8V of the rails and can achieve
current gain of 100 or more if necessary. Speed range includes video (>10
MHz).

Peter

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads