Data Sheet
Naos Raptor 6A: Non-isolated DC-DC Power Modules
December 6, 2010
4.5 – 14Vdc input; 0.59Vdc to 6Vdc Output; 6A output current
presence of a 3A to 6A step change (50% of full load),
Feature Descriptions (continued)
with an input voltage of 12V. Table 4 shows the
recommended values of RTUNE and CTUNE for different
values of ceramic output capacitors up to 1000uF, again
for an input voltage of 12V. The value of RTUNE should
never be lower than the values shown in Tables 3 and
4. 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
external R-C to tune the module for best transient
performance and stable operation for other output
capacitance values.
Vo
Rmargin-down
MODULE
Q2
Trim
Rmargin-up
VOUT
Rtrim
RTUNE
Q1
GND
MODULE
CTUNE
Figure 51. Circuit Configuration for margining
Output voltage.
TRIM
RTrim
GND
Monotonic Start-up and Shutdown
The Naos Raptor 6A modules have monotonic start-up
and shutdown behavior for any combination of rated
input voltage, output current and operating temperature
range.
Figure. 52. Circuit diagram showing connection of
R
TUME and CTUNE to tune the control loop of the
module.
Table 3. Recommended values of RTUNE and CTUNE to
obtain transient deviation of 2% of Vout for a 3A
step load with Vin=12V.
Tunable LoopTM
The Naos Raptor 6A modules have a new feature that
optimizes transient response of the module called
Tunable LoopTM. External capacitors are usually added
to improve output voltage transient response due to
load current changes. Sensitive loads may also require
additional output capacitance to reduce output ripple
and noise. 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.
Vout
5V
3.3V
2.5V
1.8V
1.2V
0.69V
2x47μF +
330μF
Polymer
330μF
Polymer
4x330μF
Polymer
Cext
2x47μF 3x47μF 4x47μF
RTUNE
CTUNE
ΔV
100
75
47
47
47
47
12nF 27nF 39nF
81mV 57mV 43mV
100nF
27mV
220nF
24mV
330nF
11mV
Table 4. General recommended values of of RTUNE
and CTUNE for Vin=12V and various external ceramic
capacitor combinations.
To use the additional external capacitors in an optimal
manner, the Tunable LoopTM feature allows the loop to
be tuned externally by connecting a series R-C between
the VOUT and TRIM pins of the module, as shown in
Fig. 52. This R-C allows the user to externally adjust
the voltage loop feedback compensation of the module
to match the filter network connected to the output of
the module.
Cext
1x47μF 2x47μF 4x47μF 10x47μF 20x47μF
RTUNE
150
100
47
47
47
CTUNE 10nF
12nF
39nF
68nF
82nF
Recommended values of RTUNE and CTUNE are given in
Tables 3 and 4. Table 3 lists recommended values of
R
TUNE and CTUNE in order to meet 2% output voltage
deviation limits for some common output voltages in the
LINEAGE POWER
16
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
