GS-R24F datasheet(7/13 Pages) STMICROELECTRONICS

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GS-R24F

Application information

7/13

4.6

Thermal shutdown

The shutdown block generates a signal that turns off the power stage if the temperature of

the internal chip goes higher than a fixed internal threshold (150

°C min).

The sensing element of the chip is very close to the PDMOS area, so ensuring an accurate

and fast temperature detection.

An hysteresis of approximately 20

°C avoids that the devices turns on and off continuously.

4.7

Output voltage programming (GS-R24F0002.0 and GS-

R24F0001.0)

The GS-R24F0002.0 output voltage is 5.54 V ±4 %, the GS-R24F0001.0 output voltage is

24.44 V ±4 %, to reduce these values connect a resistor between pin 11 (FB) and pin 10

(Vout).

The resistor must be located very close to the proper pins, to minimize the injected noise

(see figure 2).

The resistor value is calculated using the following formula:

for GS-R24F0002.0 Rv = [(Vout - 1.235) * 11.3] / (5.54 - Vout) --[kΩ];

for GS-R24F0001.0 Rv = [(Vout - 1.235) * 62] / (24.44 - Vout) --[kΩ].

Vout can be adjusted between 1.235 V (Rv = 0 Ω) and 5.54 V/24.44 V (Rv = open).

4.8

Loop compensation (GS-R24F0002.0 and GS-R24F0001.0)

If required by particular load conditions, it is possible to change the feedback loop

compensation, adding an external capacitor between pin 11 (FB) and pin 10 (Vout), which

will act as speed up (see Figure 4).

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