Thermal head driving IC and method of controlling the same
US7868907B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2008 |
| Grant date | Jan 11, 2011 |
| Priority date | — |
| Expiry date | Feb 18, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/35
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A thermal head driving IC for supplying voltage to a plurality of heating resistors each controlled by a driving MOS transistor includes a switch for making and breaking electrically between a substrate and a source of the plurality of driving MOS transistors. In a case where the plurality of heating resistors are activated, the plurality of driving MOS transistors are turned on and the switch is turned off, whereby the substrate potential is floated. As a result, the substrate potential is forward-biased against the source by a substrate current generated in a high-electric-field depletion region near the drain, and a parasitic bipolar transistor turns on, whereby both the plurality of driving MOS transistors and the parasitic bipolar transistor turn on. In a case where the plurality of heating resistors are not activated, a signal for turning off the plurality of driving NMOS transistors is given, and the switch is turned on.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.