Data Sheet

© 2009 Microchip Technology Inc. DS22039D-page 39
MCP4725
8.5.5 PROGRAMMABLE CURRENT
SOURCE
Example 8-3 illustrates an example how to convert the
DAC voltage output to a digitally selectable current
source by adding a voltage follower and a sensor
register.
FIGURE 8-3: Digitally Controllable Current Source.
LOAD
V
DD
I
L
I
B
R
SENSE
R
R
MCP4725
V
DD
V
OUT
A0
SCL
V
SS
1
2
3
4
5
6
V
DD
SDA
10 µF0.1 µF
V
DD
Dn Input Code (0 to 4095)=
I
L
V
OUT
R
SENSE
------------------
β
β 1+
-------------
=
V
OUT
V
DD
Dn
4096
------------
× =
I
B
I
L
β
----=
V
OUT
To M CU
(MASTER)