Floating Voltage Regulation For IC Chips
Original Publication Date: 1979-Feb-01
Included in the Prior Art Database: 2005-Feb-19
Integrated circuit (IC) 10 is used to turn on additional circuitry 11 located on a common substrate 12 when the emitter of Q1 is connected to a potential at least 0.7 V below the base potential V1. V1 is referenced V0 volts from the chip substrate ground 13, where V0 can be plus, zero or minus with respect to ground 13. When V0 is plus or zero, circuit operation is straightforward, with the most negative voltage on the chip occurring at the chip substrate ground 13. When V0 is negative, however, the most negative voltage on the chip will occur at the emitter of Q1. This is contrary to the general IC design rule to have the most negative potential in the circuit connected to the chip substrate, i.e., ground 13.