AUSTIN LITE 5.0V 2.5V Lineage Power, AUSTIN LITE 5.0V 2.5V Datasheet - Page 16

• Manufacturer Part Number: AUSTIN LITE 5.0V 2.5V
• Manufacturer: Lineage Power

Specifications of AUSTIN LITE 5.0V 2.5V

• Lead Free Status / RoHS Status: Not Compliant

Lineage Power
Feature Descriptions
Output Regulation
These modules make use of inherent output resistance to
facilitate improved transient response. This means that the
output voltage will decrease with increasing output current.
For this reason, the total DC regulation window at any given
operating temperature is comprised of a no-load setpoint
and a load dependent voltage drop due to module output
resistance. Regulation data provided includes both the initial
set point and this voltage drop. Production test limits are set
such that no module could pass with a full-load regulation
point equal to the maximum column. This means that at any
operating current, the regulation will always be better than
the total window specified.
Output Overcurrent Protection/Overtemperature
Protection
Current limiting is provided for momentary overloads and
short circuits. A sustained overload may cause the thermal
shutdown circuit to activate. The current limit inception is
nominally 7 amperes with the power semiconductors at
rated temperature in a 25 °C ambient environment. The ther-
mal circuitry will shut down the module at 110 °C minimum
on the power semiconductors’ top surfaces measured using
an infrared camera as described in the Thermal Ratings
Section.
Output Control
The output voltage may be margined up or down in direct
proportion to the percentage deviation of the control pin from
1.5V. The control pin may be driven by an imposed voltage
to margin up or down or shunted by a resistive element to
ground for margin down. The preferred margin technique
employs an external control voltage to margin up or down. A
resistor shunt may be used to margin down but the refer-
ence will sag due to its internal impedance.
R
Figure 46. Circuit for increasing the output voltage.
V
V
V
March 26, 2008
MARGIN
OUT
CONTROL
OUTNOM
:
:The shunt resistor to ground for margining
: The ouput voltage if the control pin is left open
: The voltage at the CTRL pin
+
–
The value of the output voltage after margining
V
CONTROL
CTRL
1.5 V
+
–
499
REFERENCE
100 µA
51.1 K
TO FB
–
+
3.3 Vdc and 5.0 Vdc Input, 1.5 Vdc - 3.3 Vdc Output, 5A
Margin Up
To margin the converter up apply a voltage to the CTRL pin
that is above 1.50 volts by the same percentage as the
desired margin up percentage.
Example:Margin up 5%: Applying 1.575 volts to the CTRL
pin will increase the output voltage by 5% over its unmar-
gined value.
Margin Down
Assume a percentage to margin down. Then connect a
resistor RMARGIN between CTRL and GND. Use the follow-
ing relations to decide the value of RMARGIN.
Figure 47. Circuit for decreasing the output voltage.
Example: To margin down 5%, then
R
Because margining affects the system reference, margining
beyond 10% is unacceptable and 0% - 5% is desirable. Mar-
gining the unit down beyond 5% requires derating the avail-
able current by 1% for every percent beyond 5 that the
module is margined down. For example, if a module were
margined down 7%, output current would have to be derated
2%.
Special Note:The 3.3/2.5V version must be operated at nominal line
MARGIN
R
MARGIN
R
MARGIN
= 9481
=
to achieve margin up.
The margin up available for this version is maximum
5%.
=
V
CONTROL
R
MARGIN
V
499
499
CONTROL
CTRL
V
•
CONTROL
•
⎛
⎝
= 1.5 (1 +
⎛
⎝
------------------------------------------- -
1 – (1 – margin%)
---------------------------- -
1 – (1 – .05)
1 – margin%
= 1.5 (1 + .05)
1 – .05
1.5 V
+
–
= 1.575
499
REFERENCE
100 µA
:
51.1 K
MARGIN UP
⎞
⎠
TO FB
⎞
⎠
%)
–
+
16