M
Marte Schwarz
- Jan 1, 1970
- 0
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
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