Quick Start Procedure - Analog Devices LINEAR DC2620A-A Demo Manual

QUICK START PROCEDURE

Figure 2 shows an application diagram using the LTC7106
with a typical DC/DC voltage regulator. By connecting
IDAC to the feedback node of the voltage regulator, IDAC
can change the output voltage of the regulator with the
equation:
 
R
FB1
 
V = V 1+   – I
OUT REF  
R
 
FB2
where V is the reference voltage of the voltage regula-
REF
tor. R and R are the resistor divider for the voltage
FB1 FB2
regulator. IDAC is the programmed bidirectional current
of the LTC7106.
V
DD
2.5V
TO 5.5V
PMBus INTERFACE
Figure 2. An Application Diagram Using the LTC7106 with a Typical DC/DC Voltage Regulator
• R
DAC FB1
C1
1µF
10k 10k 10k
R3 R2 R1
SDA
SDA
SCL
SCL
ALERT
ALERT
GND
DEMO MANUAL DC2620A-A
In order to achieve the best IDAC current accuracy of the
LTC7106, it's recommended to carefully design the volt-
age divider so that the LTC7106 uses its nominal range.
A design tool has been developed to help customers opti-
mize their design. It's built in the LTpowerCAD
tool and can be downloaded from:
http://www.linear.com/solutions/LTpowerCAD
SW
V
V
IN IN
DC/DC
V
FB
RUN
R4
10k
0 A TO 63 A
V
EN GPO
DD
LTC7106 IDAC
ASEL0 ASEL1
DC2620A-A F02
V
DD
software
®
L1
V
OUT
C2
330µF
R
FB1
V
REF
(0.4V to 2V)
R
FB2
–64 A TO 0 A
dc2620aaf
3