GS-R51212S STMicroelectronics, GS-R51212S Datasheet - Page 7

• Manufacturer Part Number: GS-R51212S
• Description: Switching Converters, Regulators & Controllers +5.1/+12/-12V Stp-Dn
• Manufacturer: STMicroelectronics
• Type: Step Downr

Specifications of GS-R51212S

• Input Voltage: 15 to 40V
• Screening Level: Commercial
• Operating Temperature Min Deg. C: 0C
• Operating Temperature Max Deg. C: 85C
• Product Depth (mm): 50.8mm
• Mounting Style: Screw
• Pin Count: 11
• Number Of Outputs: 3
• Package / Case: Module
• Lead Free Status / RoHS Status: Supplier Unconfirmed

Figure 3 - Typical Application.
Inhibit/Enable Input
The Inhibit/Enable function allows the ON/OFF
logic control of the module.
The converter is ON (Enable) when the voltage
applied to pin 2 (EN.) and referred to pin 1 (GND
IN) is lower than 0.8V (TTL, CMOS, open collector
compatible level).
The converter is OFF (Inhibit) when pin 2 is uncon-
nected or the voltage applied is in the range of 1.2V
to +Vin. Maximum sinking current is 1mA.
Module Protection
The module is protected against occasional and
permanent short-circuits of the output pins to
ground, as well as against output current overload.
The main output (+5.1V) uses a foldback current
limiting; the output current decreases with increas-
ing overload, reaching a minimum at short-circuit
condition.
This solution minimizes internal power dissipation.
The auxiliary outputs ( 12V or 15V) use a current
limiting protection circuitry.
Thermal characteristics
Sometimes the GS-R51212S and GS-R51515S re-
quire an external heat-sink depending on both op-
erating temperature conditions and power.
Before entering into calculations details, some ba-
sic concepts will be explained to better understand
the problem.
The thermal resistance between two points is rep-
resented by their temperature difference in front of
a specified dissipated power, and it is expressed in
Degree Centigrade per Watt ( C/W).
For the modules the thermal resistance case to
ambient is 7.5 C/W. This means that an internal
power dissipation of 1W will bring the case tempera-
ture at 7.5 C above the ambient temperature.
The maximum case temperature is 85 C.
Let’s suppose to have a GS-R51515S that delivers
the maximum output power of 31.4W at an ambient
temperature of 40 C.
GS-R51212S/GS-R51515S
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