High transconductance voltage reference cell
US6002293A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 1998 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Mar 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F3/30
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A high transconductance voltage reference cell produces a large change in output current for a very small change in input voltage near a settable equilibrium point, which can be made equal to two bandgap voltages, or to non-integer multiples of the bandgap voltage without the use of a resistive divider. A first and second pair of bipolar transistors, at least one of which have unequal emitter areas, are arranged in a crossed-quad configuration, with a first resistor interposed between one of the first pair and second pair transistors and a second resistor interposed between one of the second pairs' emitters and a common point. For input voltages below the equilibrium point, most of the current through the cell flows down one side of the quad. The voltage drop across the first resistor increases with input voltage, and causes the cell current to be abruptly switched from one side of the quad to the other at the equilibrium point. This large change in current induced by a small change in input voltage provides the cell's high transconductance. The cell can be made to exhibit a lower g.sub.m or some hysteresis by adjusting the relationship between the resistor values. The equilibrium …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.