Power detector utilizing bias voltage divider for precision control of an amplifier
US5043672A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 1990 |
| Grant date | Aug 27, 1991 |
| Priority date | — |
| Expiry date | Mar 26, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03G3/3042
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A controlled-output amplifier circuit whose output power may be maintained at a number of predetermined levels over a wide ambient temperature range. The amplifier includes a controllable gain amplifier stage, and a power level detector consisting of a detector diode and a linear voltage divider. The linear voltage divider is preferably composed of two resistors, with a first resistor being connected in series between a direct current (DC) voltage and the anode of the diode, and a second resistor connected between the cathode of the diode and a ground reference point. Preferably, the resistance of the first resistor is much greater than that of the second resistor. This insures that the detector bias voltage is sufficiently small so that any effects of variation in temperature are attenuated to an acceptably small level. Additionally, the first and second resistors have temperature coefficients such that the effect of the rate of change of the forward voltage drop of the detector diode with respect to temperature is reduced by the ratio of the resistance of the second resistor to that of the first resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.