Patent ID: 6515537
Filing Date: 2003-02-04
Classification: H03K

Abstract:
A method for providing a stable current source, the method comprising:(a) providing an integrated circuit comprising: an integrated circuit substrate; an oscillator formed on the substrate and operative to generate an oscillating signal characterized by a frequency; a capacitor formed on the substrate, wherein the capacitor is directly coupled with a power supply VDD; a capacitor charging circuit formed on the substrate and operative to charge the capacitor when the oscillating signal is in a first state; a capacitor discharging circuit formed on the substrate and operative to discharge the capacitor when the oscillating signal is in a second state; and a bias signal generator formed on the substrate, responsive to the capacitor, and operative to generate a bias signal at a level that varies in accordance with the frequency of the oscillating signal; wherein the oscillator is coupled with the bias signal such that the frequency of the oscillating signal varies in accordance with the bias signal; and (b) generating a stable current with the integrated circuit.