GE Industrial Solutions 12A Analog SlimLynx Open Frame - Manual (Page 13)

GE
Data Sheet
12A Analog SlimLynx TM Open Frame: Non-Isolated DC-DC Power Modules
3Vdc –14.4Vdc input; 0.6Vdc to 5.5Vdc output; 12A Output Current
February 19, 2014 ©2014 General Electric Corporation. All rights reserved. Page 13
Analog Feature Descriptions
Remote On/Off
The 12A Analog SlimLynx TM Open Frame power modules
feature an On/Off pin for remote On/Off operation. Two
On/Off logic options are available. In the Positive Logic
On/Off option, (device code suffix “4” – see Ordering
Information), the module turns ON during a logic High on the
On/Off pin and turns OFF during a logic Low. With the
Negative Logic On/Off option, (no device code suffix, see
Ordering Information), the module turns OFF during logic
High and ON during logic Low. The On/Off signal should be
always referenced to ground. For either On/Off logic option,
leaving the On/Off pin disconnected will turn the module ON
when input voltage is present.
For positive logic modules, the circuit configuration for using
the On/Off pin is shown in Figure 39. When the external
transistor Q2 is in the OFF state, the internal transistor Q7 is
turned ON, which turn Q3 OFF which keeps Q6 OFF and Q5
OFF. This allows the internal PWM #Enable signal to be
pulled up by the internal 3.3V, thus turning the module ON.
When transistor Q2 is turned ON, the On/Off pin is pulled
low, which turns Q7 OFF which turns Q3, Q6 and Q5 ON and
the internal PWM #Enable signal is pulled low and the
module is OFF. A suggested value for R
pullup
is 20k Ω.
For negative logic On/Off modules, the circuit configuration
is shown in Fig. 40. The On/Off pin should be pulled high with
an external pull-up resistor (suggested value for the 3V to
14V input range is 20Kohms). When transistor Q2 is in the
OFF state, the On/Off pin is pulled high, transistor Q3 is
turned ON. This turns Q6 ON, followed by Q5 turning ON
which pulls the internal ENABLE low and the module is OFF.
To turn the module ON, Q2 is turned ON pulling the On/Off
pin low, turning transistor Q3 OFF, which keeps Q6 and Q5
OFF resulting in the PWM Enable pin going high.
Figure 39. Circuit configuration for using positive On/Off
logic.
Figure 40. Circuit configuration for using negative On/Off
logic.
Monotonic Start-up and Shutdown
The module has monotonic start-up and shutdown behavior
for any combination of rated input voltage, output current
and operating temperature range.
Startup into Pre-biased Output
The module can start into a prebiased output as long as the
prebias voltage is 0.5V less than the set output voltage.
Analog Output Voltage Programming
The output voltage of the module is programmable to any
voltage from 0.6dc to 5.5Vdc by connecting a resistor
between the Trim and SIG_GND pins of the module. Certain
restrictions apply on the output voltage set point depending
on the input voltage. These are shown in the Output Voltage
vs. Input Voltage Set Point Area plot in Fig. 41. The Upper
Limit curve shows that for output voltages lower than 1V, the
input voltage must be lower than the maximum of 14.4V. The
Lower Limit curve shows that for output voltages higher than
0.6V, the input voltage needs to be larger than the minimum
of 3V.
Figure 41. Output Voltage vs. Input Voltage Set Point Area
plot showing limits where the output voltage can be set for
different input voltages.
V
O
(+)
TRIM
VS─
R
trim
LOAD
V
IN
(+)
ON/OFF
VS+
SIG_GND
0
2
4
6
8
10
12
14
16
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
Input V
o
lta
g
e (v
)
Output Voltage (V)
Lower
Upper
20K
Rpullup
I
20K
ON/OFF
+
20K
3.3V
470
VIN
20K
Q7
20K
100pF
4.7K
ENABLE
100K
SlimLynx Module
47K
Q2
+VIN
20K
GND
20K
20K
2K
ON/OFF
Q6
Q5
V
Q3
_
ENABLE
470
4.7K
+VIN
20K
100K
2K
100pF
_
47K
GND
Q6
20K
Q2
+
SlimLynx Module
V
Rpullup
Q3
ON/OFF
20K
ION/OFF
3.3V
Q5
20K