Intelligent switch system and assembly having integrated protection circuitry

Abstract

A switch system includes a brake pedal having a ferromagnetic target, a main housing that securely retains a brake circuit board and a magnet, a sensor connector subassembly, and a plug connector subassembly. The system also includes a connector circuit board secured within the sensor connector subassembly and in communication with the brake circuit board. The connector circuit board includes at least one positive temperature coefficient (PTC) device electrically connected between the brake circuit board and at least one brake lamp. The connector circuit board may also include at least one circuit to protect against over-voltage or over-current to the at least one brake lamp, detect a fault condition, and determine whether the plug connector subassembly is connected to the sensor connector subassembly.

1 . A system, comprising:
 a brake pedal having a ferromagnetic target;   a main housing that securely retains a brake circuit board and a magnet, wherein the brake pedal is proximate a portion of the main housing, the brake circuit board comprising:
 a first Hall device proximate the magnet, wherein the first Hall device is configured to switch in relation to a first magnetic field threshold; and 
 a second Hall device proximate the magnet, wherein the second Hall device is configured to switch in relation to a second magnetic field threshold, and wherein the first magnetic field threshold differs from the second magnetic field threshold; 
   a plug connector subassembly;   a sensor connector subassembly that is selectively connectable to the plug connector subassembly; and   a connector circuit board secured within the sensor connector subassembly and in communication with the brake circuit board, the connector circuit board comprising:
 at least one positive temperature coefficient (PTC) device electrically connected between the brake circuit board and at least one brake lamp; and 
 a circuit to protect against over-voltage or over-current to the at least one brake lamp, detect a fault condition, and determine whether the plug connector subassembly is properly connected to the sensor connector subassembly. 
   
     
     
         2 . The system of  claim 1 , wherein the connector circuit board further comprises:
 a relay switch connected between the at least one PTC and the at least one brake lamp, wherein the at least one PTC restricts current from flowing to the relay switch when current at the at least one PTC exceeds a current threshold; and   a Zener diode connected to a relay coil, wherein the Zener diode is configured to allow current to pass to the relay coil when the Zener diode experiences a breakdown voltage, thereby energizing the relay coil to move the relay switch from a closed to an open position.   
     
     
         3 . The system of  claim 2 , further comprising a metal oxide varistor (MOV) electrically connected between the relay switch and the load. 
     
     
         4 . The system of  claim 1 , wherein the connector circuit board further comprises a microcontroller electrically connected to a fault indicator. 
     
     
         5 . The system of  claim 4 , wherein the microcontroller monitors a voltage difference across the at least one PTC to determine whether to activate the fault indicator. 
     
     
         6 . The system of  claim 4 , wherein the fault indicator comprises one or more of a visual or audio indicator. 
     
     
         7 . The system of  claim 1 , wherein the connector circuit board further comprises an interlock circuit having an interlock pin, wherein the interlock circuit prevents current from flowing to the at least one brake lamp when the plug subassembly is not properly connected to the sensor connector subassembly. 
     
     
         8 . The system of  claim 7 , further comprising a transistor electrically connected to the interlock pin, wherein the transistor is on and connected to ground when the plug connector subassembly is not properly connected to the sensor connector subassembly, and wherein the transistor is off and not connected to ground when the plug connector subassembly is properly connected to the sensor connector subassembly. 
     
     
         9 . The system of  claim 1 , wherein the at least one PTC comprises at least two PTCs connected in parallel. 
     
     
         10 . The system of  claim 1 , wherein the protection against over-current or over-voltage is automatically resettable without manual intervention. 
     
     
         11 . The system of  claim 1 , wherein the magnet is a U-shaped magnet having opposed posts connected by a cross beam, wherein the opposed posts and the cross beam define an internal gap, and wherein the first and second Hall devices are positioned within the internal gap. 
     
     
         12 . The system of  claim 1 , wherein the first Hall device is operatively connected to a cruise control module, and wherein the first Hall device switches to deactivate cruise control controlled by the cruise control module. 
     
     
         13 . The system of  claim 1 , wherein the second Hall device is operatively connected to the connector circuit board, and wherein the second Hall device switches to control activation and deactivation of the at least one brake lamp. 
     
     
         14 . The system of  claim 13 , wherein the brake circuit board further comprises a relay electrically connected between the second Hall device and the at least one brake lamp. 
     
     
         15 . The system of  claim 13 , wherein the brake circuit board further comprises a field-effect transistor (FET) electrically connected between the second Hall device and the at least one brake lamp. 
     
     
         16 . The system of  claim 1 , wherein a magnetic field of the magnet changes when the ferromagnetic target moves in relation to the magnet. 
     
     
         17 . The system of  claim 1 , wherein the first and second magnetic field thresholds are first and second magnetic field strength thresholds. 
     
     
         18 . A system comprising:
 a brake circuit board comprising:
 a first Hall device proximate a magnet, wherein the first Hall device is configured to switch in relation to a first magnetic field threshold; and 
 a second Hall device proximate the magnet, wherein the second Hall device is configured to switch in relation to a second magnetic field threshold, and wherein the first magnetic field threshold differs from the second magnetic field threshold; 
   a connector circuit board secured within the sensor connector subassembly and in communication with the brake circuit board, the connector circuit board comprising:
 at least one positive temperature coefficient (PTC) device electrically connected between the brake circuit board and at least one brake lamp; and 
 at least one circuit to protect against over-voltage or over-current to the at least one brake lamp, detect a fault condition, and determine whether the plug connector subassembly is properly connected to the sensor connector subassembly. 
   
     
     
         19 . A circuit system, comprising:
 a first Hall device proximate a magnet, wherein the first Hall device is configured to switch in relation to a first magnetic field threshold;   a second Hall device proximate the magnet, wherein the second Hall device is configured to switch in relation to a second magnetic field threshold, and wherein the first magnetic field threshold differs from the second magnetic field threshold;   at least one positive temperature coefficient (PTC) device electrically connected to at least one brake lamp; and   at least one circuit to protect against over-voltage or over-current to the at least one brake lamp, detect a fault condition, and determine whether the plug connector subassembly is properly connected to the sensor connector subassembly.