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dc1830b-c/b-df
DEMO MANUAL
DC1830B-C/DC1830B-D
DESCRIPTION
LTC4000-1
Battery Charger Controller and
PowerPath Manager with
Maximum Power Point Control
Demonstration circuit 1830B is a battery charger control-
ler and PowerPath™ manager with maximum power point
control (MPPC) featuring the LTC
®
4000-1. MPPC extracts
near maximum power from high impedance sources
such as solar panels, wind turbines or fuel cells. MPPC
is achieved by means of an input voltage regulation con-
trol loop. This board should be connected to a front-end
DC/DC power supply for a complete charger solution.
The DC1830B is customizable to handle a wide variety
of applications with output voltages from 3V to 30V and
output currents up to 6.5A with the PFETs supplied, and up
to 60V and/or 13A with higher voltage rating and/or added
PFETs. The reference design provided with DC1830B is
targeted at 4-cell LiFePO
4
(14.6V/5A) applications.
The DC1830B loop compensation values were proven with
the LTC3845A buck power converter shown and are typi-
cal for other applications. The output of this demo board
was specifically tailored for a Tenergy 10A-hour battery,
P/N 30207. Other voltages can be set by changing ROFB2
and RBFB2. The desired nominal voltage can be accurately
trimmed by using trim resistors ROFBX and RBFBX. For
example, for 14.4V battery float voltage, change ROFB2
and RBFB2 to 86.6k, and add 7.5M at ROFBX and RBFBX
for greater setpoint accuracy. Other parameters can be ad-
justed to suit specific applications with guidance provided
in the LTC4000-1 data sheet. Table 1 provides a summary
of parameter adjustments.
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
This circuit was designed to demonstrate the high levels
of performance and small solution size attainable using
this part to control a switch mode power converter to
form a battery charger, intelligent PowerPath manager and
power supply system. It produces a regulated 5.0A/14.6V
battery charger output as well as a system output of up to
5.5A: suitable for a wide variety of portable applications
including instruments, industrial equipment, power tools
and computers.
The DC1830B-C provides a solution complete with both
battery charger control and PowerPath management. It
includes a second PFET (Q2) between VOUT-SYS and
BAT to provide “instant-on” functionality which keeps
VOUT-SYS within a narrow range regardless of battery
voltage, and disconnects the battery when it is fully charged
and power is available from the front-end DC/DC converter.
Thermal regulation circuitry is also provided to limit the
temperature of both PFETs.
The DC1830B-D provides a simple battery-charger-con-
troller-only solution without the PowerPath manager. It
deletes the second PFET and thermal regulation circuitry.
In this case, the battery is always “online” and VOUT-SYS
tracks the BAT voltage.
Design files for this circuit board are available at
http://www.linear.com/demo
