Vicor VI-J00 Family DC-DC Converters and Configurable Power Supplies - Manual (Page 31)

Design Guide & Applications Manual
For VI-200 and VI-J00 Family DC-DC Converters and Configurable Power Supplies
VI-200 and VI-J00 Family Design Guide Rev 3.5 vicorpower.com
Page 30 of 98
Apps. Eng. 800 927.9474 800 735.6200
OVERVIEW
The BatMod is a programmable current source module
that is intended for battery charging or simular current
source applications. It can be controlled externally to meet
a wide range of charging parameters: voltage, current,
charge rate and charge time.
The BatMod is comparable to the VI-200 voltage source
module but with a variable current limit. It has three
output pins that differ from the VI-200 converters:
Current Control (I
TRIM ), Voltage Adjust (V TRIM ) and Current
Monitor (I
MON
). All of these pins are referenced to the
–OUT pin.
Although the BatMod is primarily intended for battery
charge applications it can be used as a programmable
current source for resistive loads or CW laser diodes. The
BatMod will not function properly at zero output voltage
and current simultaneously. It follows therefore that the
current can not be adjusted to zero with a resistive load.
Refer to Safe Operating Area Curves on the
BatMod data
sheet , which can be found at vicorpower.com.
PINOUT DESCRIPTION
Current Control (I TRIM ). An input which can receive an
analog control voltage from 1 – 5 V for adjustment of the
sourced current from zero to maximum rating of the BatMod.
Voltage Adjust (V
TRIM
). An input for controlling or
setting the output setpoint, this is similar to the trim
function on the VI-200. (Section 5) A maximum voltage
can be set by a fixed resistor or adjusted with an external
voltage source. A source voltage referenced to –OUT
adjusted from 1.25 – 2.5 V will program a 50 – 100% of
rated voltage setting.
It is important to note the nominal output voltage for
each BatMod type untrimmed.
12 Vout Part # = 15 V actual
24 Vout Part # = 30 V actual
48 Vout Part # = 60 V actual
Current Monitor (I
MON
). An output that indicates the
amount of current being sourced. It is a linear voltage /
current relationship where one volt corresponds to 0%
of sourced current and 5 V corresponds to 100% of
sourced current.
For DC input / current source applications (Figure 11–1),
the BatMod has a similar wide range input rating as the
VI-200 Family of voltage converters for 48 and 300 V
inputs. BatMods can be used for higher current source
applications with a Driver / Booster approach. (Figure 11–2)
NOTE: Inductance to the load should be limited to
20 µH to avoid possible loop instabilities.
2.5 Vdc Max. Vout
=
1.25 Vdc 50% of Vout
5 Vdc 100% of Rating
=
1 Vdc 0 Amps
5 Vdc 100% of Rating
=
1 Vdc 0 Amps
DC Input BatMod
GATE
IN
GATE
OUT
+OUT
–OUT
+IN
–IN
External
Control
Functions
+
–
Load
TRIM V
TRIM I
MON I
Figure 11–1 — DC input single module
DC Input BatMod
GATE
IN
GATE
OUT
+OUT
–OUT
V
I
MON
+IN
–IN
External
Control
Functions
GATE
IN
GATE
OUT
+OUT
–OUT
+IN
–IN
BatMod
Booster
GATE
IN
GATE
OUT
+OUT
–OUT
+IN
–IN
Enable/
Disable
+
–
Load
TRIM
TRIM
I
BatMod
Booster
Figure 11–2 — DC input high power array
11. Battery Charger (BatMod)