High-voltage-tolerant pull-up resistor circuit
US9634662B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 2014 |
| Grant date | Apr 25, 2017 |
| Priority date | — |
| Expiry date | Nov 19, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/018507
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A pull-up resistor circuit is provided for an IC, including a voltage source, a voltage output for providing a first voltage to supply power for providing a second voltage for an input/output (I/O) port of the IC, a first PMOS transistor, a second PMOS transistor and a control signal generator. The first PMOS transistor and the second PMOS transistor are connected in series to provide pull-up resistance, where the first PMOS transistor is coupled to a first control signal to control a pull-up function of the pull-up resistor circuit in a normal mode. Further, the control signal generator is for generating a second control signal coupled to the second PMOS transistor to control a bias voltage of the pull-up resistor circuit to prevent a reverse current from the voltage output to the voltage source under a high-voltage-tolerant mode when the second voltage is higher than the first voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.