GS-R51212S STMicroelectronics, GS-R51212S Datasheet

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... Reset output Power Fail programmable input Inhibit/Enable control input Soft-start PCB or chassis mounting DESCRIPTION The GS-R51212S and GS-R51515S are versatile triple output, high current step-down switching regulators that provide +5.1V/4.5A output voltage and an isolated 12V/0.35A or output voltage. They are ideal for microprocessor based boards ...

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... V Load Regulation 1 OO1 V Load Regulation 2,3 OO2 Output Current Output Current 2* GS-R51212S I o2 Output Current 2* GS-R51515S I o2 Output Current 2* GS-R51212S Io2 Output Current 2* GS-R51515S Io3 Output Current 3* GS-R51212S 2 unless otherwise specified) amb Test Conditions +5. 4. +12V 0.35A – 12V – 0.35A ...

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... Test Conditions 40V 4. – 15V 0. 40V 4. – 12V 40V 4. – 15V 40V Overload 40V 40V 40V 5. 0 +12/+15V – 12/– 15V – 0.05 to – 0.35/– 0. 24V I o1,2,3 = Full Load GS-R51212S/GS-R51515S Min Typ Max Unit 0 – 0 – 0 – 0 100 ms ...

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... GS-R51212S/GS-R51515S CONNECTION DIAGRAM AND MECHANICAL DATA Package R. Dimensions in mm (inches). PIN DESCRIPTION Pin Function 1 GND IN Return for input voltage source. Internally connected to pin 7. Inhibit/Enable control input. The converter is ON (ENABLE) when the voltage applied to 2 EN. this pin is lower than 0.8V. The converter is OFF (INHIBIT) when this pin is unconnected or the input voltage is in the range of 1 ...

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... Fail Input) and pin 1 (GND Input). The value of Rpf must be calculated accord- ing to the following formula where Vpf is the desired value of Power Fail thresh- old voltage. of 100ms DR Exampe: Vpf = 24V (must not be lower than 12V GS-R51212S/GS-R51515S = 200mV. 5 5.1 pf 0.191 34 5.1 14k 24 5 ...

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... GS-R51212S/GS-R51515S Figure 2 - Reset and Power Fail waveforms. Auxiliary Outputs The auxiliary outputs ( 12V or 15V) are externally adjustable in symmetric way by connecting a resistor Ra between pin 10 (ADJ.) and pin 8 (Vo + 12/+15V), according to the following formula: GS R51212S R 32. R51515S R 38.66 a 6/8 where V is the desired dual output voltage. ...

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... This solution minimizes internal power dissipation. The auxiliary outputs ( 12V or 15V) use a current limiting protection circuitry. GS-R51212S/GS-R51515S 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 ...

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... GS-R51212S/GS-R51515S The dissipated power in this operating condition is about 7.4W (at typical efficiency of 81%), and the case temperature of the module will be case amb d This value exceeds the maximum allowed tempera- ture and an external heat-sink must be added. To this purpose four holes (see mechanical drawing) are provided on the metal surface of the module. To calculate this heat-sink, let’ ...