Data Sheet
Austin Lynx
TM
II: SIP Non-Isolated DC-DC Power Modules
2.4Vdc –5.5Vdc input; 0.75Vdc to 3.63Vdc output; 10A Output Current
©2015 General Electric Company. All rights reserved.
Page
Feature Description
Remote On/Off
The Austin Lynx
TM
II SIP power modules feature an On/Off pin
for remote On/Off operation. Two On/Off logic options are
available in the Austin Lynx
TM
II series modules. Positive Logic
On/Off signal, device code suffix “4”, turns the module ON
during a logic High on the On/Off pin and turns the module OFF
during a logic Low. Negative logic On/Off signal, no device
code suffix, turns the module OFF during logic High on the
On/Off pin and turns the module ON during logic Low.
For positive logic modules, the circuit configuration for using
the On/Off pin is shown in Figure 29. The On/Off pin is an open
collector/drain logic input signal (Von/Off) that is referenced to
ground. During a logic-high (On/Off pin is pulled high internal
to the module) when the transistor Q1 is in the Off state, the
power module is ON. Maximum allowable leakage current of
the transistor when Von/off = V
IN,max
is 10µA. Applying a logic-
low when the transistor Q1 is turned-On, the power module is
OFF. During this state VOn/Off must be less than 0.3V. When
not using positive logic On/off pin, leave the pin unconnected
or tie to V
IN.
Q1
R2
R1
Q2
R3
R4
Q3
CSS
GND
VIN+
ON/OFF
PWM Enable
+
_
ON/OFF
V
I
ON/OFF
MODULE
Figure 29. Circuit configuration for using positive logic
On/OFF.
For negative logic On/Off devices, the circuit configuration is
shown is Figure 30. The On/Off pin is pulled high with an
external pull-up resistor (typical R
pull-up = 5k, +/- 5%). When
transistor Q1 is in the Off state, logic High is applied to the
On/Off pin and the power module is Off. The minimum On/off
voltage for logic High on the On/Off pin is 1.5Vdc. To turn the
module ON, logic Low is applied to the On/Off pin by turning
ON Q1. When not using the negative logic On/Off, leave the
pin unconnected or tie to GND.
Q1
R1
R2
Q2
CSS
GND
PWM Enable
ON/OFF
VIN+
ON/OFF
_
+
V
I
MODULE
pull-up
R
ON/OFF
Figure 30. Circuit configuration for using negative logic
On/OFF.
Overcurrent Protection
To provide protection in a fault (output overload) condition, the
unit is equipped with internal current-limiting circuitry and can
endure current limiting continuously. At the point of
current-limit inception, the unit enters hiccup mode. The unit
operates normally once the output current is brought back into
its specified range. The typical average output current during
hiccup is 3.0A.
Input Undervoltage Lockout
At input voltages below the input undervoltage lockout limit,
module operation is disabled. The module will begin to operate
at an input voltage above the undervoltage lockout turn-on
threshold.
Overtemperature Protection
To provide protection in a fault condition, the unit is
equipped with a thermal shutdown circuit. The unit will
shutdown if the thermal reference point T
ref
, exceeds 125
o
C
(typical), but the thermal shutdown is not intended as a
guarantee that the unit will survive temperatures beyond its
rating. The module will automatically restarts after it cools
down.
