Mini MOSFET Slide Switch with Reverse Voltage Protection, LV

₪30

תיאור

This product is a power switch implemented as a pair of P-channel MOSFETs configured as a high-side switch with reverse voltage protection and controlled by a micro slide switch. Because the main current does not go through the controlling mechanical switch, a variety of switches can be used without concern for the current they can carry. For example, a small slide or toggle switch can be mounted conveniently on a control panel with thin wires running to it, while the main power path can be shorter and with thicker wires. Pushbutton or tactile switches can also be used for momentary switching applications.

Unlike the Pololu Pushbutton Power Switches, which can lose their state when power is disconnected and reapplied, the conducting state of the MOSFET Slide Switches is determined only by the physical control switch (or a signal supplied to the “ON” pin), independent of power applied to the board. This can make them more appropriate for applications where the supplied power may be intermittent.

Thermal and power dissipation considerations

Because MOSFETs in the on state are effectively resistive, the power heating the board is proportional to the square of the current flowing through it. The comparison table near the top of this page shows typical currents that heat the MOSFETs to 55°C, where the MOSFETs start being noticeably warm but are still generally safe to touch, and currents that heat the MOSFETs to 150°C, the absolute limit for the MOSFETs. With adequate cooling, or for brief periods if the MOSFETs are not hot to begin with, currents up to the listed maximums are attainable.

Transient protection

Interrupting large currents can cause voltage spikes (positive on the input side and negative on the output side) that depend on the inductance of the power connections and that can exceed the limits of the device. Appropriate measures to limit the size of these spikes include minimizing lengths of wires, placing capacitors at the power switch to smooth the spikes and absorb some of the energy, placing a

schottky diode across the power output to absorb negative spikes, and placing a transient voltage suppressor (TVS) across the power input to absorb positive spikes.