Temperature compensated avalanche photodiode optical receiver circuit
US4438348A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1978 |
| Grant date | Mar 20, 1984 |
| Priority date | — |
| Expiry date | Oct 6, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/6911
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A photodiode receiver circuit having self-contained automatic gain control and which is temperature compensated over a wide operating range contains a resistor coupled in series between a bias power supply and one end of an avalanche photodiode. Self-generated AGC action results from the fact that the gain of an avalanche photodiode increases as the bias voltage applied across the diode increases. As the light intensity received by the diode increases, there is a corresponding increase in the current flow through the diode and the series-connected resistor. The consequential increase in IR drop across the resistor decreases the bias voltage across the diode, so that the gain of the diode is reduced. Through this action, the dynamic range of optical input of the photodiode will be increased for a fixed dynamic range of electrical output. Temperature compensation is achieved by coupling a temperature-sensitive voltage divider circuit between the bias voltage supply and the gain-controlling resistor. This voltage divider network may include a thermistor coupled in parallel with one resistor component of a resistor divider that is connected to a bias voltage source. The value of the pa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.