AFBR-1521CZ Datasheet, PDF (1/10 Pages) Broadcom Corporation. – Cost-Effective 650 nm LED Transmitter Driver for DC-5MBd Application for 3.3V Power Supply Voltage

AFBR-1521CZ, AFBR-1531CZ, AFBR-1541CZ
Cost-Effective 650 nm LED Transmitter Driver for
DC-5MBd Application for 3.3V Power Supply Voltage
Application Note
Introduction
Avago Technologies manufactures fiber-optic components for
industrial, medical, transportation, power generation, and
gaming markets. Its products have been adopted in various
applications for years since it started producing fiber-optic
components. Avago Technologies offers both discrete and
integrated fiber-optic components that can be easily designed
into customer systems. Integrated transmitters incorporate the
driving circuit with the product, while discrete transmitters
require customers to design the transmitter driving circuit.
The advantage of using discrete components is the flexibility in
designing optical link solutions that are optimized for the
target customer application.
Objective
Avago Technologies supports its customers to implement
cost-effective components to interface with its products. This
application note (AN) describes the logic device SN74LVC86Ax
by Texas Instruments for creating a light emitting diode (LED)
driver circuit operating at 3.3V. The driving circuit for analog
transmitters offers flexibility in design and requires only a low
component count.
New Driver for 3.3V Operations
For best performance and optimum matching with Avago´s
optical parts, the SN74LVC86Ax logic integrated circuit (IC) is
described in this AN. This AN provides details about LED driver
circuits for Avago Technologies' discrete fiber-optic
transmitters of the versatile link product family AFBR-15x1CZ
with an LED at 650 nm.
The LED driver circuit is recommended to create optical links
with versatile link fiber-optic receivers at supply voltage levels
of 3.3 V, such as AFBR-25x1CZ.
The quadruple 2-input exclusive-or gate SN74LVC86Ax at
Vcc = 3.3V shows comparable performance to the Vcc = 5.0V
compatible logic devices, such as 74ACT[Q]00xx (NAND gate)
or 74ACT08Mxx (AND gate) as mentioned in the optical
transmitter data sheets.
NOTE
All data shown in this AN is based on tests
with one driver IC SN74LVC86AD and three
transmitter samples of the versatile link
product family AFBR-15x1CZ.
Test data shown in this application note reflects the typical
behavior of the tested fiber-optic transmitters in combination
with the specific driver IC and does not cover worst case
conditions.
The schematic shown in this application note is a
recommendation and Avago Technologies cannot guarantee
full function and performance. The designer should perform
his own verification.
Broadcom
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