12 including diodes z 1 and z 2 as they relate to the integrated circuit structure of device 12 illustrated and described with respect to fig3 are correspondingly numbered parenthetically in fig5 for cross reference in any event unlike circuit 12 of fig2 the anode of diode z 2 in circuit 100 is not connected to vss directly but is rather switchable between v bat and vss through low resistance paths illustrated symbolically by resistors ra and rb respectively specifically the circuitry 102 of the present invention includes a switch 104 connected to the anode of z 2 wherein activation of the switch 104 is controlled by the voltage polarity of v bat with respect to vss as shown schematically by signal line 106 if v bat is negative with respect to vss switch 104 is connected to low resistance path ra to thereby pull the anode of diode z 2 isolation region 36 of fig3 near v bat if on the other hand v bat is positive with respect to vss switch 104 is connected to low resistance path rb to thereby pull the anode of diode z 2 isolation region 36 of fig3 to a potential near vss it is to be understood that v bat is in one embodiment representative of the battery voltage of an automotive battery not shown but may alternatively be any voltage supply referring now to fig5 one preferred embodiment of the high side driver circuit 100 of fig4 in accordance with the present invention is shown circuit 100 of fig5 includes the.