Hi, I found a schematic for a low voltage reference in LM311 datasheets from National, TI and ST. It looks like:
VCC | \\ / R1 \\ 3.9k / | ,-----+ | | | | | |/c Q1 +---| 2N3708 (Si), 2N797 (Ge) or 2N1304 (Ge) | |>e | | | | | +-------Uref | | | | | |/c Q2 '---| 2N2222 |>e | | | gnd
followed by a LM311 as a noninverting operational amplifier (!?!)
I want to understand this and need a little help. As I play a few with spice it seems to give a voltage about a few ten mV but not really like a reference source. What is the benefit of this schematic and how does it work?
Marte