Datasheet

LT6654
11
6654fa
Figure 4. LT6654-2.5 Sourcing and Sinking 0.5mA
Figure 5. LT6654-2.5 Sourcing 4mA to 5mA
Figure 6. LT6654-2.5 Sinking 4mA to 5mA
50µs/DIV
I
OUT
–0.5mA
V
OUT
20mV/DIV/AC
2.5V/DC
6654 F04
C
LOAD
= 1µF
0.5mA
APPLICATIONS INFORMATION
50µs/DIV
I
OUT
4mA
V
OUT
10mV/DIV/AC
2.5V/DC
6654 F05
C
LOAD
= 1µF
5mA
50µs/DIV
I
OUT
–5mA
V
OUT
1
0mV/DIV/AC
2.5V/DC
6654 F06
C
LOAD
= 1µF
–4mA
Positive or Negative Operation
In addition to the series connection, as shown on the front
page of this data sheet, the LT6654 can be operated as a
negative voltage reference.
The circuit in Figure 7 shows an LT6654 confi gured for
negative operation. In this confi guration, a positive volt-
age is required at V
IN
(Pin 4) to bias the LT6654 internal
circuitry. This voltage must be current limited with R1 to
keep the output PNP transistor from turning on and driv-
ing the grounded output. C1 provides stability during load
transients. This connection maintains the same accuracy and
temperature coeffi cient of the positive connected LT6654.
Figure 7. Using the LT6654-2.5 to Build a –2.5V Reference
LT6654-2.5
6
4
1, 2
V
EE
V
OUT
= –2.5V
0.1µF
3V
R1
4.7k
6654 F07
C1
1µF
V
EE
– V
OUT
550µA + I
OUT
R ≤