Datasheet

ADR360/ADR361/ADR363/ADR364/ADR365/ADR366
Rev. D | Page 18 of 20
General-Purpose Current Source
Often in low power applications, the need arises for a precision
current source that can operate on low supply voltages. The
ADR36x can be configured as a precision current source (see
Figure 36). The circuit configuration illustrated is a floating
current source with a grounded load. The output voltage of the
reference is bootstrapped across R
SET
, which sets the output
current of the load. With this configuration, circuit precision is
maintained for load currents ranging from the reference’s
supply current, typically 150 μA, up to approximately 5 mA.
NC
GND
V
IN
ADR36x
TRIM
V
OUT
1
2
3
5
4
I
SY
I
SET
+ I
SY
I
SET
R1
P
1
+V
DD
R
L
05467-028
R
SET
Figure 36. Precision Current Source
Trim Terminal
The ADR36x trim terminal can be used to adjust the output
voltage over a nominal voltage. This feature allows a system
designer to trim system errors by setting the reference to a
voltage other than the standard voltage option. Resistor R1 is
used for fine adjustments and can be omitted if desired. The
resistor values should be carefully chosen to ensure that the
maximum current drive of the part is not exceeded.
05467-029
1
2
3
5
4
+
V
DD
NC
GND
V
IN
ADR36x
TRIM
V
OUT
V
OUT
R1
100kΩ
POT
10kΩ
R2
1kΩ
Figure 37. ADR36x Trim Configuration