Integrated generator of a slow voltage ramp
US6384645B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 2001 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Apr 2, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K4/023
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An integrated circuit for producing a small slope voltage ramp includes a circuit for generating a periodic triangular current signal, and a circuit for generating, at the beginning of each period of the triangular signal, a pulse of a certain duration which is much smaller than the period of the triangular signal. A control loop is input at a node with the triangular current signal and produces the desired slow voltage ramp on the output node. The control loop includes a first hold circuit coupled to the input node via a first switch controlled by the pulse, and a transconductance operational amplifier, whose inputs are respectively coupled to the input node and to the output node. Also, the control loop includes a second hold circuit coupled to the output of the operational transconductance amplifier via a second switch controlled in a complementary manner with respect to the first switch. A resistor of a much smaller value than the ratio between the period of the triangular signal and the capacitance of the storage capacitor of the first hold circuit is connected between the output of the second hold circuit and the input node.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.