Laser circuits

This circuit was originally designed to detect laser light pulses for an optical Ethernet communications system. It has good ambient light immu

This circuit was originally designed to detect laser light pulses for an optical Ethernet communications system. It has good ambient light immunity.

The SFP Digital Diagnostics Development Board is a platform designed to enable optical module designers to develop SFP and SFF compliant transceivers with digital diagnostics. The same platform can be used to develop the digital diagnostics section for other 2-wire based ID and diagnostics functions, such as the ones found in GBIC, 300 pin MSA, XFP, and other optical MSAs.

This circuit takes advantage of some new vertical cavity surface emitting lasers (VCSEL) that don’t require light output control circuits. The circuit shows how to drive the device from a single high speed CMOS IC. The circuit can easily be modified to transmit signals from kilohertz to about 50MHz.

This circuit was originally designed to detect weak flashed of laser light bounced off of a fabric video projection screen. It was used as part of a firearm training system. It generates a 100mS output pulse whenever it detects a 3ms to 5ms-laser burst, modulated at 40KHz. It is very sensitive and could be modified for long-range laser communications.

This application note describes the ADN2841 laser diode driver evaluation kit. The evaluation kit is a demonstration board that provides electrical evaluation of the ADN2841. This document describes how to configure the board in order to operate the part electrically. The document contains the following information: • Board description • Quick start for electrical operation • Description of board settings • Component list • Schematic of board • Silkscreen image of board

The ADN2847 is a 3 V dual-loop 50 Mbps to 3.3 Gbps laser diode driver. To use the board in an optical configuration, a suitable laser diode must be soldered onto the board. The monitor photodiode (MPD) current is fed into the ADN2847 to control the average power and extinction ratio.

This application note describes the optical channel identification feature implemented on the Analog Devices’ ADN284x series of laser drivers.

The ADN8810 is a 12-bit, high output current D/A converter that is controlled through a serial peripheral interface (SPI). The device can be used as a current source for tunable lasers or other precision high output current applications, like 4–20 mA control loops. Refer to the ADN8810 data sheet for technical specifi cations.

Inexpensive, 16-bit, monolithic DACs can serve almost all applications. However, some applications require unconventional approaches. This Design Idea design concerns circuitry I recently designed for a tunable-diode laser spectrometer for a Mars-exploration application. The control circuitry included two 16-bit DACs that interface to the radiation-hardened, 8051-variant 69RH051A microcontroller.