Abstract:
A rectifier driving circuit of the present invention, has a first driving element and a second driving element, switching element comprises a FET, a first driving element comprises the voltage drop resistor, a second driving element comprises the series-connected circuit of the diodes, the driving element for driving a FET, may be achieved rectify function.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention related to a first driving element, a second driving element and an enhancement mode FET for rectifier driving circuit, especially FET there is not an intrinsic body diode can be achieve rectify function. 
         [0003]    2. Description of Related Arc 
         [0004]      FIG. 7  shown a structures of the prior art half-wave rectifier. In this figure, FET F 1  is responsible for rectification. In operation, when positive of AC power source in the terminal A, terminal B is negative, FET F 1  turned on, FET F 1  acts as a rectifier, the path of the current flow is from terminal A of AC power source though a load LD, FET F 1  and back to terminal B; when negative of AC power source in the terminal A, terminal B is positive, FET F 1  turned off, the path of the current flow is from terminal B of AC power source though intrinsic body diode DB of the FET F 1 , a load LD and back to terminal A, may be burnout by current of the prior art FET F 1 , and FET F 1  having no responsible for rectification. 
       SUMMARY OF THE INVENTION 
       [0005]    In order to provide a first driving element, a second driving element FET having no intrinsic body diode that may elevate the efficiency of half-wave rectifier, the present invention is proposed the following object: 
         [0006]    The first object of the present invention provide a driving circuit for a rectifier, in which the rectifier simplicity is improved. 
         [0007]    The second object of the present invention provide a diode parallel to the FET for surge current protection. 
         [0008]    According to the defects of the prior art technology discussed above, a novel solution, the rectifier driving circuit is proposed in the present invention, which provides simplicity and for surge current protection in rectifier circuit. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  shown the structures of a prior art N-Channel FET. 
           [0010]      FIG. 2  shown the structures a having no intrinsic body diode N-Channel FET. 
           [0011]      FIG. 3  shown the structures of a diode parallel to the N-Channel FET, a P-junction of the diode connected to drain of the N-Channel FET, a N-junction of the diode connected to source of the N-Channel FET. 
           [0012]      FIG. 4  shown the structures of a prior art P-Channel FET. 
           [0013]      FIG. 5  shown the structures a having no intrinsic body diode P-Channel FET. 
           [0014]      FIG. 6  shown the structures of a diode parallel to the P-Channel FET, a N-junction of the diode connected to drain of the P-Channel FET, a P-junction of the diode connected to source of the P-Channel FET. 
           [0015]      FIG. 7  is a circuit diagram of a prior art N-Channel FET for half-wave rectifier circuit. 
           [0016]      FIG. 8  is a circuit diagram of a first embodiment of the present invention. 
           [0017]      FIG. 9  is a circuit diagram of a second embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0018]      FIG. 1  shows the structures of a prior art N-Channel FET, a N-junction of the intrinsic body diode DB connected to drain of the prior art N-Channel FET, a P-junction of the intrinsic body diode DB connected to source of the prior art N-Channel FET. 
         [0019]      FIG. 2  shows the structures of a N-Channel FET having no intrinsic body diode, has a enhancement mode FET. 
         [0020]      FIG. 3  shows the structures of a diode parallel to the N-Channel FET, a diode parallel to the N-Channel FET for surge current protection in the rectify circuit. 
         [0021]      FIG. 4  shows the structures of a prior art P-Channel FET, a P-junction of the intrinsic body diode DB connected to drain of the prior art P-Channel FET, a N-junction of the intrinsic body diode DB connected to source of the prior art P-Channel FET. 
         [0022]      FIG. 5  shows the structures of a P-Channel FET having no intrinsic body diode, has a enhancement mode FET. 
         [0023]      FIG. 6  shows the structures of a diode parallel to the P-Channel FET, a diode parallel to the P-Channel FET for surge current protection in the rectify circuit. 
         [0024]    As shown in  FIG. 8 , has a AC power source input terminal, a first terminal A and second terminal B of the input terminal, a N-Channel FET Q 1 , a first driving element R 1 , a second driving element D 1 , D 2  . . . DN, and a load LD. 
         [0025]    A inrush diode DP parallel to the N-Channel FET Q 1  shown in  FIG. 8 , a driving circuit comprises a voltage drop resistor R 1  and a diode D 1  or series-connected with D 1 , D 2  . . . DN diodes; the P-junction of D 1 , D 2  . . . DN diodes connected to gate of the N-Channel PET Q 1 , the N-junction of D 1 , D 2  . . . DN diodes connected to source of the N-Channel FET Q 1 , the driving voltage is equal to the forward voltage of series-connected of D 1 , D 2  . . . DN diodes. 
         [0026]    As shown in  FIG. 8 , when positive of AC power source in the terminal A, terminal B is negative, the P-junction is positive of the series-connected D 1 , D 2  . . . DN diodes, the N-junction is negative of the series-connected of D 1 , D 2  . . . DN diodes, the N-Channel FET Q 1  is turned on, the driving voltage is equal to the forward voltage of series-connected of D 1 , D 2  . . . DN diodes, the path of the current flows is from terminal A of the AC power source though a load LD, a N-Channel FET Q 1 , and back to terminal B of the AC power source. 
         [0027]    As shown in  FIG. 8 , when negative of AC power source in the terminal A, terminal B is positive, the P-junction is negative of the series-connected of D 1 , D 2  . . . DN diodes, the N-junction is positive of the series-connected of D 1 , D 2  . . . DN diodes, the N-Channel FET Q 1  is turned off, the rectifier is open circuit. 
         [0028]    As shown in  FIG. 9 , has a AC power source input terminal, a first terminal A and second terminal B of the input terminal, a P-Channel FET Q 2 , a first driving element R 1 , a second driving element D 1  . . . DN, and a load LD. 
         [0029]    A surge diode DP parallel to the P-Channel FET shown in  FIG. 9 , a driving circuit comprises a voltage drop resistor R 1  and a diode D 1  or series-connected with D 1 , D 2  . . . DN diodes; the N-junction of D 1 , D 2  . . . DN diodes connected to gate of the P-Channel PET Q 2 , the P-junction of D 1 , D 2  . . . DN diodes connected to source of the P-Channel PET Q 2 , the driving voltage is equal to the forward voltage of series-connected of D 1 , D 2  . . . DN diodes. 
         [0030]    As shown in  FIG. 9 , when positive of AC power source in the terminal A, terminal B is negative, the P-junction of the diode D 1  is positive of the series-connected D 1 , D 2  . . . DN diodes, the N-junction of the diode DN is negative of the series-connected of D 1 , D 2  . . . DN diodes, the P-Channel FET Q 2  is turned on, the driving voltage is equal to the forward voltage of series-connected of D 1 , D 2  . . . DN diodes, the path of the current flows is from terminal A of the AC power source though a P-Channel FET Q 2 , a load LD, and back to terminal B of the AC power source. 
         [0031]    As shown in  FIG. 9 , when negative of AC power source in the terminal A, terminal B is positive, the P-junction is negative of the diode D 1  of the series-connected of D 1 , D 2  . . . DN diodes, the N-junction of the diode DN is positive of the series-connected of D 1 , D 2  . . . DN diodes, the P-Channel FET Q 2  is turned off, the rectifier is open circuit. 
         [0032]    The operation principle of the second driving element D 1 , D 2  . . . DN of  FIG. 8  and the second driving element D 1 , D 2  . . . DN of  FIG. 9  is same, both of the second driving element can be use a series-connected circuit of diode and zener diode replace, the driving voltage is equal to the forward voltage of diode and zener voltage of zener.