MAX3746 19-3386 Rev 2 6/07 Low-Power, 622Mbps to 3.2Gbps Limiting Amplifier General Description Features The MAX3746 multirate limiting amplifier functions as a SFP Reference Design Available data quantizer for SONET, Fibre-Channel, and Gigabit Low 115mW Power Consumption Ethernet optical receivers. The amplifier accepts a wide range of input voltages and provides selectable-level, 16-Pin QFN Package with 3mm x 3mm Footprint current-mode logic (CML) output voltages with con- 70ps Rise and Fall Time trolled edge speeds. A received-signal-strength indica- tor (RSSI) is available when the MAX3746 is Loss-of-Signal with Programmable Threshold DC-coupled to the MAX3744/MAX3724 SFP transim- RSSI Interface (with MAX3744/MAX3724 TIA) pedance amplifier (TIA). A receiver consisting of the MAX3744/MAX3724 and the MAX3746 can provide up Output Disable to 19dB RSSI dynamic range. Additional features Polarity Select include a programmable loss-of-signal (LOS) detect, an optional disable function (DISABLE), and an 8.4ps Deterministic Jitter (3.2Gbps) P-P output-signal polarity reversal (OUTPOL). Output dis- Improved EMI Performance able can be used to implement squelch. The combination of the MAX3746 and the MAX3744/ Selectable CML Output levels MAX3724 allows for the implementation of all the small- Pin Compatible with MAX3748A form-factor SFF-8472 digital diagnostic specifications using a standard 4-pin TO-46 header. Ordering Information The MAX3746 is pin-for-pin compatible with the PIN- MAX3748A limiting amplifier and consumes 30% less PART TEMP RANGE PKG CODE PACKAGE power. The MAX3746 is packaged in a 3mm x 3mm, 16-pin QFN package. MAX3746ETE -40C to +85C 16 Thin QFN T1633F-3 MAX3746HETE* -40C to +85C 16 Thin QFN T1633F-3 Applications *The MAX3746HETE is a hybrid lead-free package. See the Gigabit Ethernet SFF/SFP Transceiver Modules Detailed Description section for more information. Fibre-Channel SFF/SFP Transceiver Modules Pin Configuration appears at end of data sheet. Multirate OC-12 to OC48-FEC SFF/SFP Typical Operating Circuits continued at end of data sheet. Transceiver Modules Typical Operating Circuits SFP OPTICAL RECEIVER HOST BOARD SUPPLY FILTER HOST FILTER 4-PIN TO HEADER V RX CC OUTPOL VCC 0.1F IN+ OUT+ 50 SERDES 0.1F MAX3744 TIA IN- OUT- 50 MAX3746 RSSI TH GND DISABLE LOS 4.7k TO 10k 2.97V TO 3.6V R = 14k TH DS1859 3-INPUT DIAGNOSTIC LOS MONITOR R1 C1 3k 0.1F Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Low-Power, 622Mbps to 3.2Gbps Limiting Amplifier ABSOLUTE MAXIMUM RATINGS Power-Supply Voltage (V ).................................-0.5V to +4.5V Continuous Power Dissipation (T = + 70C) CC A Voltage at IN+, IN- ..........................(V - 2.4V) to (V + 0.5V) 16-Pin QFN (derate 17.7mW above +70C) .....................1.4W CC CC Voltage at DISABLE, OUTPOL, RSSI, Operating Junction Temperature Range (T )....-55C to +150C J LOS, TH...................................................-0.5V to (V + 0.5V) Storage Ambient Temperature Range (Ts) .......-55C to +150C CC Current into LOS.....................................................1mA to +9mA Differential Input Voltage (IN+ - IN-) .....................................2.5V Continuous Current at CML Outputs (OUT+, OUT-) ................................................-25mA to +25mA Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (V = +2.97V to +3.63V, CML output load is 50 to V , T = -40C to +85C, unless otherwise noted. Typical values are at V = CC CC A CC +3.3V, T = +25C, unless otherwise specified. The data input transition time is controlled by 4th-order Bessel filter with f = 0.75 x A -3dB 2.667GHz for all data rates of 2.667Gbps and below, and with f = 0.75 x 3.2GHz for a data rate of 3.2Gbps.) -3dB PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Single-Ended Input Resistance R Single ended to V 42 50 58 IN CC se S S i ngl e ended , f < 3G Hz, DU T is p ow er ed on 14 11 Input Return Loss dB diff S Differential, f < 3GHz, DUT is powered on 15 11 Input Sensitivity V (Note 1) 2 4 mV IN-MIN P-P Input Overload V (Note 1) 1200 mV IN-MAX P-P Single-Ended Output Resistance R Single ended to V 42 50 58 OUT CC Output Return Loss diff S Differential, f < 3GHz, DUT is powered on 20 dB 22 4mV < V < 1200mV , P-P IN P-P 600 800 1000 OUTPOL connected to V or GND CC CML Differential Output Voltage mV P-P 4mV < V < 1200mV , P-P IN P-P 400 500 600 OUTPOL open or connected to 30k Differential Output Signal when Outputs AC-coupled, 10 mV P-P Disabled V applied to input (Note 2) IN-MAX K28.5 pattern at 3.2Gbps (Note 2) 8.4 18 K28.5 pattern at 3.2Gbps at T = +100C 10.2 A 23 2 - 1 PRBS equivalent at 2.7Gbps (Note 2) 11.6 23 23 2 - 1 PRBS equivalent pattern at 2.7Gbps 13.1 at T = +100C A Deterministic Jitter DJ K28.5 pattern at 2.1Gbps 8 20 ps P-P (Note 3) K28.5 pattern at 2.1Gbps at T = +100C 9.7 A 23 2 - 1 PRBS equivalent pattern at 622Mbps 42.5 69 (Note 2) 23 2 - 1 PRBS equivalent pattern at 622Mbps 47.8 at T = +100C A 2 MAX3746