Patent · US Expired

Variable frequency charge pump

US6060932A · kind A · utility

15Cited by
7References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 17, 1998
Grant dateMay 9, 2000
Priority date
Expiry dateJul 17, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M3/07
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

In integrated circuits, to modify the operation of the charge pumps or voltage step-up circuits, they are sent a variable frequency signal at the input with the aim of breaking the regularity of the pulse train that enters the charge pump. This limits the risks of entry into resonance and limits radiation at a given frequency. The variable frequency signal is typically produced by a logic circuit and by a main oscillator whose transmission of certain pulses is masked by the combined action of different masking signals. The duty cycle ratios of the masking signals are less than that of the signal from the main oscillator. Such duty cycle ratios are preferably produced following the passage of a signal to a lower frequency than that of the signal of the main oscillator in a circuit for the detection of high transitions.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.