Linear Technology DC1780A-B Demo Manual

DESCRIPTION
Demonstration circuit 1780A-B features PolyPhase
®
design using the LTM 4620EV, the high efficiency, high
density, dual 13A, switch mode step-down power module
regulator. The input voltage is from 4.5V to 16V. The
output voltage is jumper selectable from 1.0V to 2.5V.
DC1780A-B can deliver nominal 75A output current with
3× LTM4620s in parallel. As explained in the data sheet,
output current derating is necessary for certain V
and thermal conditions. The LTM4620 on DC1780A-B
always operates in continuous conduction mode. The
switching frequency can be programmed through a resistor
or can be synchronized to an external clock signal. The
board allows the user to program how its output voltage
ramps up and down through the TRACK_CONTROL pin.
BOARD PHOTO
®
, V ,
IN OUT
Figure 1. 75A PolyPhase LTM4620/DC1780A-B Demo Board
DEMO MANUAL DC1780A-B
LTM4620EV: High Efficiency,
PolyPhase 75A Step-Down
Power µModule
The output voltage is tightly regulated between V
–
and V through remote output voltage sensing which
OUT
improves output voltage regulation at heavy loads. These
features and the availability of the LTM4620EV in a compact
15mm × 15mm × 4.41mm LGA package make it ideal for
use in many high density point-of-load regulation applica-
tions. The LTM4620 data sheet must be read in conjunction
with this demo manual prior to working on or modifying
the demo circuit DC1780A-B.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Linear Technology, the Linear logo, μModule and PolyPhase are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
Regulator
®
+
OUT
dc1780abfa
1