Voltage programmable power dissipater
US6448992B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 7, 2001 |
| Grant date | Sep 10, 2002 |
| Priority date | — |
| Expiry date | Nov 7, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/00014
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Apparatus herein provides for a chosen level of power dissipation of a resistor, for example, the heating element of a thermal head assembly. The resistance of the resistor changes upon a change in temperature thereof, for example, due to increased flow of current therethrough. The apparatus includes a resistive shunt in series with the resistor, a first differential amplifier, with voltage drop across the resistor being provided to first and second input terminals of the first differential amplifier, and a second differential amplifier, voltage drop across the shunt being provided to first and second input terminals of the second differential amplifier. The output signals from the first and second differential amplifiers are provided to a voltage multiplier. The output signal from the voltage multiplier is provided to an input terminal of a power operational amplifier, and a programming sequence voltage is supplied to another input terminal of the power operational amplifier. The output signal from the power operational amplifier is provided to the resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.