Over-voltage protection circuit

Abstract

A network device comprising an integrated circuit configured for coupling to lines between a network connector and an Ethernet physical layer (PHY) and comprising a diode bridge and protection circuitry integrated onto a common integrated circuit whereby parasitics in an energy discharge path and stress on the PHY and the diode bridge are reduced.

1 . A network device comprising: 
 a protection circuit configured for coupling to lines between a network connector and an Ethernet physical layer (PHY), the protection circuit comprising a diode bridge and protection circuitry integrated onto a common integrated circuit.    
   
   
       2 . The network device according to  claim 1  further comprising: 
 the protection circuit configured for coupling lines between the network connector and the Ethernet physical layer (PHY) that carry signal and power in a Power-over-Ethernet arrangement.    
   
   
       3 . The network device according to  claim 1  further comprising: 
 the protection circuit diode bridge coupled to center taps of an Ethernet transformer coupled to the lines between the network connector and the Ethernet physical layer (PHY).    
   
   
       4 . The network device according to  claim 1  further comprising: 
 the protection circuit diode bridge coupled to a T-Less Connect™ solid-state transformer coupled to the lines between the network connector and the Ethernet physical layer (PHY).    
   
   
       5 . The network device according to  claim 1  further comprising: 
 the protection circuit comprising: 
 the integrated diode bridge coupled between a supply line and a reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line; and  
 a power switch coupled to the supply line and controlled by the protection circuitry.  
   
   
   
       6 . The network device according to  claim 1  further comprising: 
 the protection circuit comprising: 
 the integrated diode bridge coupled between a supply line and a reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line; and  
 a p-channel power switch Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) coupled to the supply line and controlled by the protection circuitry.  
   
   
   
       7 . The network device according to  claim 1  further comprising: 
 the protection circuit comprising: 
 the integrated diode bridge coupled between a supply line and a reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line;  
 a power switch integrated into the protection circuit and coupled to the supply line and controlled by the protection circuitry; and  
 a Powered Device (PD) controller integrated into the protection circuit and coupled between the supply line and the reference line.  
   
   
   
       8 . The network device according to  claim 1  further comprising: 
 a power transformer coupled between a supply line and a reference line;    at least one capacitor coupled between the supply line and the reference line;    a switch coupled to the reference line; and    the protection circuit comprising: 
 the integrated diode bridge coupled between the supply line and the reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line;  
 a power switch integrated into the protection circuit and coupled to the supply line and controlled by the protection circuitry; and  
 a pulse width modulator integrated into the protection circuit, coupled between the supply line and the reference line, and configured to control the switch.  
   
   
   
       9 . The network device according to  claim 1  further comprising: 
 a wall jack power source;    an Alternating Current (AC) charger coupled to the wall jack power source and coupled between a supply line and a reference line;    at least one capacitor coupled between the supply line and the reference line;    a switch coupled to the reference line; and    the protection circuit comprising: 
 the integrated diode bridge coupled between the supply line and the reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line; and  
 a power switch integrated into the protection circuit and coupled to the supply line and controlled by the protection circuitry.  
   
   
   
       10 . A network device comprising: 
 an integrated circuit configured for coupling to lines between a network connector and an Ethernet physical layer (PHY) and comprising a diode bridge and protection circuitry integrated onto a common integrated circuit whereby parasitics in an energy discharge path and stress on the PHY and the diode bridge are reduced.    
   
   
       11 . The network device according to  claim 10  further comprising: 
 at least one capacitor coupled between a supply line and a reference line; and    the integrated circuit comprising: 
 the integrated diode bridge coupled between the supply line and the reference line;  
 a p-channel power switch Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) coupled to the supply line; and  
 the integrated protection circuitry coupled between the supply line and the reference line, and having a rail clamp control line coupled to the p-channel power switch MOSFET that turns on the p-channel power switch MOSFET hard in a surge condition whereby charge is redirected to a capacitor of the at least one capacitor.  
   
   
   
       12 . The network device according to  claim 10  further comprising: 
 at least one capacitor coupled between a supply line and a reference line; and    the integrated circuit comprising: 
 the integrated diode bridge coupled between the supply line and the reference line;  
 a p-channel power switch Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) coupled to the supply line; and  
 the integrated protection circuitry coupled between the supply line and the reference line, the integrated circuit configured whereby a high frequency strike short-circuits a capacitor of the at least one capacitor and passes to ground.  
   
   
   
       13 . The network device according to  claim 10  further comprising: 
 a power transformer coupled between a supply line and a reference line;    a wall jack power source;    an Alternating Current (AC) charger coupled to the wall jack power source and coupled between a supply line and a reference line;    at least one capacitor coupled between the supply line and the reference line;    a switch coupled to the reference line; and    the integrated circuit comprising: 
 the integrated diode bridge coupled between the supply line and the reference line;  
 the integrated protection circuitry coupled between the supply line and the reference line;  
 a power switch integrated into the integrated circuit and coupled to the supply line and controlled by the protection circuitry; and  
 a pulse width modulator integrated into the integrated circuit, coupled between the supply line and the reference line, and configured to control the switch.  
   
   
   
       14 . A network device comprising: 
 an over-voltage protection integrated circuit configured for usage in a Power-over-Ethernet (PoE) application coupling to lines between a network connector and an Ethernet physical layer (PHY) comprising: 
 a diode bridge integrated into the over-voltage protection integrated circuit coupled between a supply line and a reference line;  
 a integrated protection circuitry integrated into the over-voltage protection integrated circuit coupled between the supply line and the reference line; and  
 a power switch integrated into the over-voltage protection integrated circuit coupled to the supply line and controlled by the protection circuitry.  
   
   
   
       15 . The network device according to  claim 14  wherein: 
 the power switch is a p-channel power switch Metal Oxide Semiconductor Field-Effect Transistor (MOSFET).    
   
   
       16 . The network device according to  claim 14  further comprising: 
 the over-voltage protection integrated circuit further comprising: 
 a Powered Device (PD) controller integrated into the over-voltage protection circuit and coupled between the supply line and the reference line.  
   
   
   
       17 . The network device according to  claim 14  further comprising: 
 the diode bridge coupled to center taps of an Ethernet transformer coupled to the lines between the network connector and the Ethernet physical layer (PHY).    
   
   
       18 . The network device according to  claim 14  further comprising: 
 the diode bridge coupled to a T-Less Connect™ solid-state transformer coupled to the lines between the network connector and the Ethernet physical layer (PHY).    
   
   
       19 . A method for over-voltage protection in a network device comprising: 
 integrating a diode bridge and protection circuitry into a common integrated circuit;    forming a supply line and a reference line in the integrated circuit;    coupling the diode bridge and the protection circuitry between the supply line and the reference line;    integrating a power switch into the common integrated circuit;    coupling the power switch to the supply line; and    controlling the power switch via the protection circuitry.    
   
   
       20 . The method according to  claim 19  further comprising: 
 coupling the common integrated circuit to lines between a network connector and an Ethernet physical layer (PHY); and    reducing parasitics in an energy discharge path;    reducing stress on the Ethernet physical layer (PHY) and the diode bridge.    
   
   
       21 . The method according to  claim 19  further comprising: 
 protecting against over-voltage in a Power-over-Ethernet (PoE) configuration.