Digital Laser Diode Driver Interface Enhances SFP+ Optical Module Controller

Jan. 31, 2011
$jq().ready( function() \{ setupSidebarImageList(); \} );

SFF-8472 standard

The small-form-factor pluggable (SFP) module is probably the most popular optical transceiver format for both data communications and telecommunications applications. These transceivers run at data speeds to 10 Gbits/s, so they’re a challenge to implement. Now, Maxim Integrated Products is making life easier for designers of SFP modules by introducing the DS1878, a small-form-factor pluggable plus (SFP+) controller with a digital laser diode driver (LDD) interface. State-machine-based, the DS1878 eliminates the need for software development. It enables efficient implementation of the SFF-8472 specification and greatly reduces time-to-market.

The SFF-8472 standard defines digital monitoring and diagnostics functions. The DS1878 implements these controls and monitors all functions for small-form-factor (SFF), SFP, and SFP+ optical modules and fully supports the SFF-8472 standard (see the figure). It can be combined with a MAX3798 or MAX3799 SFP+ laser driver/limiting amplifier to provide an automatic power control (APC) loop, modulation current control, and eye safety functionality—the core feature set of SFP and SFP+ optical modules. The DS1878 also works with the MAX3945 limiting amplifier or the MAX3946 LDD to support 10-GHz applications featuring distributed feedback (DFB) or electro-absorption-modulated (EML) lasers.

Laser modulation is controlled with a dedicated temperature-driven lookup table (LUT). Two additional 9-bit delta-sigma digital-to-analog converter (DAC) outputs with 36-entry LUTs are provided. The DS1878 monitors six analog channels: temperature, VCC, and MON1 to MON4, which can be used to monitor laser current, optical output power, and optical input power.

The DS1878 is specified from –40°C to 95°C. It uses 0.35-μm technology to enable the high level of integration required for SFF-8472 implementation in a small 5- by 5-mm, 28-pin thin quad flat no leads (TQFN) package with exposed pad. Pricing begins at $1.33 in 1000-unit quantities.

Maxim Integrated Products

Sponsored Recommendations

Board-Mount DC/DC Converters in Medical Applications

March 27, 2024
AC/DC or board-mount DC/DC converters provide power for medical devices. This article explains why isolation might be needed and which safety standards apply.

Use Rugged Multiband Antennas to Solve the Mobile Connectivity Challenge

March 27, 2024
Selecting and using antennas for mobile applications requires attention to electrical, mechanical, and environmental characteristics: TE modules can help.

Out-of-the-box Cellular and Wi-Fi connectivity with AWS IoT ExpressLink

March 27, 2024
This demo shows how to enroll LTE-M and Wi-Fi evaluation boards with AWS IoT Core, set up a Connected Health Solution as well as AWS AT commands and AWS IoT ExpressLink security...

How to Quickly Leverage Bluetooth AoA and AoD for Indoor Logistics Tracking

March 27, 2024
Real-time asset tracking is an important aspect of Industry 4.0. Various technologies are available for deploying Real-Time Location.

Comments

To join the conversation, and become an exclusive member of Electronic Design, create an account today!