Negative Voltage circuit

Since this chip require negative voltage so this it another problem to solve because if we use power supply then it is fine we can use dual power supply to supply negative voltage without a problem. In order to supply the negative voltage without a power supply is challenging therefore more research needed to be done.  Based on my research and found out a chip which can be supplied a negative voltage. This problem can be solved by implementing this chip into our PCM encoder circuit. As shown in figure is the circuit that will supply the negative voltage and in that circuit the capacitor are very important factor for generating the negative voltage.