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
Tunable LoopTM
The 12V Micro TLynxTM 12A modules have a new
external R-C to tune the module for best transient
performance and stable operation for other output
capacitance values or input voltages other than 12V.
feature that optimizes transient response of the module
called Tunable LoopTM
.
Table 2. General recommended values of of RTUNE
and CTUNE for Vin=12V and various external ceramic
capacitor combinations.
External capacitors are usually added to the output of
the module for two reasons: to reduce output ripple and
noise (see Figure 41) and to reduce output voltage
deviations from the steady-state value in the presence
of dynamic load current changes. Adding external
capacitance however affects the voltage control loop of
the module, typically causing the loop to slow down with
sluggish response. Larger values of external
capacitance could also cause the module to become
unstable.
Co
1x47μF 2x47μF 4x47μF 10x47μF 20x47μF
RTUNE
470
270
150
150
150
CTUNE 1000pF 3300pF 4700pF 8200pF
12nF
Table 3. Recommended values of RTUNE and CTUNE to
obtain transient deviation of 2% of Vout for a 6A
step load with Vin=12V.
The Tunable LoopTM allows the user to externally adjust
the voltage control loop to match the filter network
connected to the output of the module. The Tunable
LoopTM is implemented by connecting a series R-C
between the SENSE and TRIM pins of the module, as
shown in Fig. 48. This R-C allows the user to externally
adjust the voltage loop feedback compensation of the
module.
Vo
5V
3.3V
2.5V
1.8V
1.2V
0.69V
1x47μF 2x47μF 6x47μF 6x47μF 4x47μF
+
+
+
+
+
Co
4x47μF
330μF 330μF 330μF 2x330μF 6x330μF
Polymer Polymer Polymer Polymer Polymer
RTUNE
CTUNE
ΔV
270
220
220
220
150
33nF
23mV
150
3300pF 4700pF 6800pF 18nF
91mV 60mV 47mV 35mV
100nF
12mV
Recommended values of RTUNE and CTUNE for different
output capacitor combinations are given in Tables 2 and
3. Table 2 shows the recommended values of RTUNE and
CTUNE for different values of ceramic output capacitors
up to 940μF that might be needed for an application to
meet output ripple and noise requirements. Selecting
RTUNE and CTUNE according to Table 2 will ensure stable
operation of the module
VOUT
SENSE
RTUNE
CTUNE
C O
MODULE
TRIM
RTrim
GND
Figure. 48. Circuit diagram showing connection of
RTUME and CTUNE to tune the control loop of the
module.
In applications with tight output voltage limits in the
presence of dynamic current loading, additional output
capacitance will be required. Table 3 lists recommended
values of RTUNE and CTUNE in order to meet 2% output
voltage deviation limits for some common output
voltages in the presence of a 6A to 12A step change
(50% of full load), with an input voltage of 12V.
Please contact your Lineage Power technical
representative to obtain more details of this feature as
well as for guidelines on how to select the right value of
LINEAGE POWER
18
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