Data Sheet
12V Micro TLynxTM: Non-isolated DC-DC Power Modules
September 8, 2009
4.5 – 14Vdc input; 0.69Vdc to 5.5Vdc output; 12A output current
Test Configurations
Design Considerations
Input Filtering
CURRENT PROBE
TO OSCILLOSCOPE
The 12V Micro TLynxTM module should be connected
to a low ac-impedance source. A highly inductive
source can affect the stability of the module. An input
LTEST
VIN(+)
1μH
capacitance must be placed directly adjacent to the
input pin of the module, to minimize input ripple
voltage and ensure module stability.
CIN
CS 1000μF
Electrolytic
2x100μF
Tantalum
E.S.R.<0.1Ω
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 1x22 µF or 2x22
µF ceramic capacitors and an input of 12V.
@ 20°C 100kHz
COM
NOTE: Measure input reflected ripple current with a simulated
source inductance (LTEST) of 1μH. Capacitor CS offsets
possible battery impedance. Measure current as shown
above.
300
1x22uF
250
Figure 37. Input Reflected Ripple Current Test
Setup.
2x22uF
200
COPPER STRIP
150
100
50
RESISTIVE
Vo+
LOAD
10uF
0.1uF
0
COM
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
SCOPE USING
BNC SOCKET
GROUND PLANE
Output Voltage (Vdc)
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 40. Input ripple voltage for various output
voltages with 1x22 µF or 2x22 µF ceramic
capacitors at the input (12A load). Input voltage is
12V.
Figure 38. Output Ripple and Noise Test Setup.
Output Filtering
The 12V Micro TLynxTM 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.
Rdistribution Rcontact
Rcontact Rdistribution
VIN(+)
VO
RLOAD
VO
VIN
Rdistribution Rcontact
Rcontact Rdistribution
COM
COM
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.
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
Figure 39. Output Voltage and Efficiency Test Setup.
VO. IO
capacitance values at various Vo and for full load
currents of 12A. For stable operation of the module, limit
the capacitance to less than the maximum output
capacitance as specified in the electrical specification
table. Optimal performance of the module can be
Efficiency
=
x
100 %
η
VIN. IIN
LINEAGE POWER
13
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
