Rainbow Electronics MAX3795 - Manual

General Description
The MAX3795 is a high-speed VCSEL driver for small-
form-factor (SFF) and small-form-factor pluggable (SFP)
fiber optic transmitters. It contains a bias generator, a
laser modulator, and comprehensive safety features.
The automatic power control (APC) adjusts the laser
bias current to maintain average optical power over
changes in temperature and laser properties. The dri-
ver accommodates common-cathode and differential
configurations.
The MAX3795 operates up to 4.25Gbps. It can switch
up to 15mA of laser modulation current and source up
to 15mA of bias current. Adjustable temperature com-
pensation is provided to keep the optical extinction
ratio within specifications over the operating tempera-
ture range. The MAX3795 interfaces with the Dallas
DS1856/DS1859 to meet SFF-8472 timing and diagnos-
tic requirements. The MAX3795 accommodates various
VCSEL packages, including low-cost TO-46 headers.
The MAX3795 safety circuit detects faults that could
cause hazardous light levels and disables the VCSEL
output. The safety circuits are compliant with SFF and
SFP multisource agreements (MSAs).
The MAX3795 is available in a compact 4mm ✕ 4mm,
24-pin thin QFN package and operates over the -40°C
to +85°C temperature range. The MAX3795 is pin-for-
pin compatible with the MAX3740A and is available in
lead-free packages.
Applications
Multirate (1Gbps to 4.25Gbps) SFP/SFF Modules
Gigabit Ethernet Optical Transmitters
Fibre-Channel Optical Transmitters
Features
♦ Supports All SFF-8472 Digital Diagnostics
♦ 3.3V ±10% Single Supply
♦ 2mA to 15mA Modulation Current
♦ 1mA to 15mA Bias Current
♦ 52ps Transition Time
♦ 8.4ps Deterministic Jitter
♦ Optional Peaking Current to Improve VCSEL Edge
Speed
♦ Supports Common-Cathode and Differential
Configuration
♦ Safety Circuits Compliant with SFF and SFP
MSAs
♦ Pin Compatible to MAX3740A
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL
Driver with Diagnostic Monitors
________________________________________________________________ Maxim Integrated Products 1
Ordering Information
19-3387; Rev 0; 8/04
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART TEMP RANGE PIN-PACKAGE
MAX3795ETG -40°C to +85°C 24 Thi n QFN ( 4m m x 4m m )
MAX3795ETG+ -40°C to +85°C 24 Thi n QFN ( 4m m x 4m m )
24 23 22 21 20 19
PWRMON REF MD COMP V
CC
BIASMON
7 8 9 10 11 12
V
CC
TC1 TC2 GND
MODSET PEAKSET
13
14
15
16
17
18
EXPOSED PAD IS CONNECTED TO GND
GND
OUT-
OUT+
V CC
BIASSET
BIAS
6
5
4
3
2
1
SQUELCH
FAULT
IN-
IN+
TX_DISABLE
GND
MAX3795
THIN QFN (4mm x 4mm)
TOP VIEW
Pin Configuration
+Denotes lead-free package.