Data Sheet
Austin LynxTM II 12V SIP Non-isolated Power Modules:
March 30, 2008
8.3 – 14Vdc input; 0.75Vdc to 5.5Vdc Output; 10A output current
Tools section, helps determine the required external trim
resistor needed for a specific output voltage.
Feature Descriptions (continued)
The amount of power delivered by the module is defined
as the voltage at the output terminals multiplied by the
output current. When using the trim feature, the output
voltage of the module can be increased, which at the
same output current would increase the power output of
the module. Care should be taken to ensure that the
maximum output power of the module remains at or
below the maximum rated power (Pmax = Vo,set x Io,max).
Output Voltage Programming
The output voltage of the Austin LynxTM II SMT can be
programmed to any voltage from 0.75 Vdc to 5.5 Vdc by
connecting a single resistor (shown as Rtrim in Figure
29) between the TRIM and GND pins of the module.
Without an external resistor between the TRIM pin and
the ground, the output voltage of the module is 0.7525
Vdc. To calculate the value of the resistor Rtrim for a
particular output voltage Vo, use the following equation:
Voltage Margining
Output voltage margining can be implemented in the
Austin LynxTM II modules by connecting a resistor,
Rmargin-up, from the Trim pin to the ground pin for
margining-up the output voltage and by connecting a
resistor, Rmargin-down, from the Trim pin to the Output pin
for margining-down. Figure 30 shows the circuit
configuration for output voltage margining. The POL
Programming Tool, available at www.lineagepower.com
under the Design Tools section, also calculates the
values of Rmargin-up and Rmargin-down for a specific output
voltage and % margin. Please consult your local
Lineage Power technical representative for additional
details.
10500
⎡
⎤
Rtrim =
−1000 Ω
⎢
⎥
Vo − 0.7525
⎣
⎦
For example, to program the output voltage of the
Austin LynxTM II module to 1.8 Vdc, Rtrim is calculated is
follows:
10500
⎡
⎤
Rtrim =
−1000
⎢
⎣
⎥
⎦
1.8 − 0.75
Rtrim = 9.024kΩ
VIN(+)
VO(+)
Vo
Rmargin-down
LOAD
ON/OFF
TRIM
Austin Lynx or
Lynx II Series
R
trim
Q2
GND
Trim
Rmargin-up
Figure 29. Circuit configuration to program output
voltage using an external resistor.
Rtrim
Table 1 provides Rtrim values required for some
common output voltages.
Q1
Table 1
GND
VO, (V)
0.7525
1.2
Rtrim (KΩ)
Open
22.46
Figure 30. Circuit Configuration for margining
Output voltage.
1.5
13.05
1.8
9.024
2.5
5.009
3.3
3.122
5.0
1.472
By a using 1% tolerance trim resistor, set point
tolerance of ±2% is achieved as specified in the
electrical specification. ThePOL Programming Tool,
available at www.lineagepower.com under the Design
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