Lineage Power 11
Data Sheet
March 28, 2008
3.0 Vdc - 5.5 Vdc Input, 0.9 Vdc - 3.3 Vdc Output, 10 A
Austin Lynx
TM
SMT Non-Isolated dc-dc Power Modules:
Feature Descriptions (continued)
Output Voltage Set-Point Adjustment (Trim)
(contin-
ued)
Figure 22. Circuit Configuration to trim-down
output voltage.
For Trim-up using an external voltage source, apply a voltage
from TRIM pin to ground using the following equation:
For Trim-down using an external voltage source, apply a volt-
age from TRIM pin to ground using the following equation:
Vtrim-up is the external source voltage for trim-up
Vtrim-down is the external source voltage for trim-down
|ΔVout| is the desired output voltage set-point adjustment
Rbuffer (internal to the module) is defined in Table 1 for vari-
ous models
If the TRIM feature is not being used, leave the TRIM pin dis-
connected.
Remote Sense
Austin Lynx™ SMT power modules offer an option for a
Remote-Sense function. When the Device Code description
includes a suffix “3”, pin 3 is added to the module and the
Remote-Sense is an active feature. See the Ordering Infor-
mation at the end of this document for more information.
Remote Sense minimizes the effects of distribution losses by
regulating the voltage at the load via the SENSE and GND
connections (See 23). The voltage between the SENSE pin
and VO pin must not exceed 0.5V. Although both the
Remote-Sense and Trim features can each increase the out-
put voltage (VO), the maximum increase is not the sum of
both. The maximum VO increase is the larger of either the
Remote Sense or the Trim.
The amount of power delivered by the module is defined as
the output voltage multiplied by the output current (VO x IO).
When using SENSE and/or TRIM, the output voltage of the
module can increase which, if the same output current is
maintained, increases the power output by the module. Make
sure that the maximum output power of the module remains
at or below the maximum rated power. When pin 3 is present
but the Remote Sense feature is not being used, leave Sense
pin disconnected.
Figure 23. Effective Circuit Configuration for Remote
Sense Operation.
Overtemperature Protection
To provide additional protection in a fault condition, the unit is
equipped with a nonlatched thermal shutdown circuit. The
shutdown circuit engages when Q1 or Q2 (shown in Figure
24) exceeds approximately 110 °C. The unit attempts to
restart when Q1 or Q2 cool down and cycles on and off while
the fault condition exists. Recovery from shutdown is accom-
plished when the cause of the overtemperature condition is
removed.
Overcurrent Protection
To provide protection in a fault condition, the unit is equipped
with internal overcurrent protection. The unit operates nor-
mally once the fault condition is removed.
The power module will supply up to 170% of rated current for
less than 1.25 seconds before it enters thermal shutdown.
V
out
2.5V=
R
buffer
78.7k=
R
trim down–
2.5 0.8–
0.2
---------------------
1–
⎝⎠
⎛⎞
x30100 78700–=
R
trim down–
147.05kΩ=
VO
TRIM
Rtrim-down
RLOAD
GND
V
trim-up
0.8 ΔV
out
x
R
buffer
30100
------------------
–=
V
trim-down
0.8 ΔV
out
x
R
buffer
30100
------------------
+=
V
I
V
O
LOAD
GND
DISTRIBUTION LOSSES DISTRIBUTION LOSSES
SENSE
