Low level input voltage comparator
US6198312A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 1999 |
| Grant date | Mar 6, 2001 |
| Priority date | — |
| Expiry date | Nov 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K5/2472
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit and a method for comparing an input voltage to an internally generated reference voltage utilize a bias network to make the voltage comparison. The bias network is preferably configured to generate a proportional-to-absolute-temperature (PTAT) reference voltage, which is used for the voltage comparison. Although the circuit can be implemented to operate in a number of applications, the circuit is particularly useful in a current sensing application. The circuit includes the bias network, a comparison current path and an output terminal. The comparison current path is configured to partially duplicate a current path of the bias network on which the reference voltage is generated. The comparison current path includes a current control element and an active transistor. Depending on the input voltage applied to the active transistor of the comparison current path, the output terminal is driven to generate either a high or a low comparison signal. In a first embodiment, the circuit is configured to sense voltages near the supply voltage. In a second embodiment, the circuit is configured to sense voltages near the electrical ground. In either embodiments, the circuit requires a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.