Data Sheet
September 4, 2009
12V Pico TLynx
TM
6A: Non-isolated DC-DC Power Modules
4.5 – 14Vdc input; 0.59Vdc to 5.5Vdc output; 6A output current
LINEAGE POWER 12
Test Configurations
TO OSCILLOSCOPE
CURRENT PROBE
L
TEST
1μH
BATTERY
C
S
1000μF
Electrolytic
E.S.R.<0.1Ω
@ 20°C 100kHz
2x100μF
Tantalum
V
IN
(+)
COM
NOTE: Measure input reflected ripple current with a simulated
source inductance (L
TEST
) of 1μH. Capacitor C
S
offsets
possible battery impedance. Measure current as shown
above.
C
IN
Figure 37. Input Reflected Ripple Current Test
Setup.
NOTE: All voltage measurements to be t aken at the module
terminals, as sho wn above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid me asurement errors due to socket contact
resistance.
Vo+
COM
0.1uF
RESISTIVE
LOAD
SCOPE U SING
BNC SOCK ET
COPPER STRIP
GROUND PLANE
10uF
Figure 38. Output Ripple and Noise Test Setup.
V
O
COM
V
IN
(+)
COM
R
LOAD
R
contact
R
distribution
R
contact
R
distribution
R
contact
R
contact
R
distribution
R
distribution
V
IN
V
O
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
Figure 39. Output Voltage and Efficiency Test
Setup.
η
=
V
O
. I
O
V
IN
. I
IN
x
100
%
Efficiency
Design Considerations
Input Filtering
The 12V Pico TLynx
TM
6A module should be
connected to a low ac-impedance source. A highly
inductive source can affect the stability of the
module. An input capacitance must be placed
directly adjacent to the input pin of the module, to
minimize input ripple voltage and ensure module
stability.
To minimize input voltage ripple, ceramic
capacitors are recommended at the input of the
module. Figure 40 shows the input ripple voltage
for various output voltages at 6A of load current
with 1x10 µF or 1x22 µF ceramic capacitors and
an input of 12V.
Input Ripple Voltage (mVp-p)
0
50
100
150
200
250
300
350
400
450
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5
1x10uF
1x22uF
Output Voltage (Vdc)
Figure 40. Input ripple voltage for various output
voltages with 1x10 µF or 1x22 µF ceramic
capacitors at the input (6A load). Input voltage is
12V.
Output Filtering
The 12V Pico TLynx
TM
6A modules are designed for
low output ripple voltage and will meet the maximum
output ripple specification with 0.1 µF ceramic and 10
µF ceramic capacitors at the output of the module.
However, additional output filtering may be required
by the system designer for a number of reasons.
First, there may be a need to further reduce the
output ripple and noise of the module. Second, the
dynamic response characteristics may need to be
customized to a particular load step change.
To reduce the output ripple and improve the dynamic
response to a step load change, additional
capacitance at the output can be used. Low ESR
polymer and ceramic capacitors are recommended to
improve the dynamic response of the module. Figure
41 provides output ripple information for different
external capacitance values at various Vo and for a
load current of 6A. For stable operation of the
module, limit the capacitance to less than the
