MAX3941 19-2935 Rev 0 7/03 10Gbps EAM Driver with Integrated Bias Network General Description Features The MAX3941 is designed to drive an electro-absorp- On-Chip Bias Network tion modulator (EAM) at data rates up to 10.7Gbps. It 23ps Edge Speed incorporates the functions of a biasing circuit and a Programmable Modulation Voltage Up to 3V P-P modulation circuit, with integrated control op amps Programmable EAM Biasing Voltage Up to 1.25V externally programmed by DC voltages. Selectable Data-Retiming Latch The integrated bias circuit provides a programmable Up to 10.7Gbps Operation biasing current up to 50mA. This bias current reflects a bias voltage of up to 1.25V on an external 50 load. The Integrated Modulation and Biasing Functions bias and modulation circuits are internally connected on 50 On-Chip Input and Output Terminations chip, eliminating the need for an external bias inductor. Pulse-Width Adjustment A high-bandwidth, fully differential signal path is internally Enable and Polarity Controls implemented to minimize jitter accumulation. When a ESD Protection clock signal is available, the integrated data-retiming function can be selected to reject input-signal jitter. Ordering Information The MAX3941 receives differential CML signals (ground referenced) with on-chip line terminations of 50 . The PART TEMP RANGE PIN-PACKAGE output has a 50 resistor for back termination and is 24-Thin QFN MAX3941ETG -40C to +85C able to deliver a modulation current of 40mA to P-P (4mm x 4mm) 120mA , with an edge speed of 23ps (20% to 80% P-P typ). This modulation current reflects an EAM modula- Applications tion voltage of 1.0V to 3.0V . P-P P-P SONET OC-192 and SDH STM-64 The MAX3941 also includes an adjustable pulse-width Transmission Systems control circuit to precompensate for asymmetrical EAM characteristics. It is available in a compact 4mm x DWDM Systems 4mm, 24-pin thin QFN package and operates over the Long/Short-Reach Optical Transmitters -40C to +85C temperature range. 10Gbps Ethernet Typical Application Circuit -5.2V PLRT MODEN RTEN GND 0.01 F 50 DATA+ DATA+ EAM 0.01 F MAX3952 DATA- 50 DATA- 10Gbps SERIALIZER MAX3941 0.01 F 50 CLK+ CLK+ 50 OUT 0.01 F CLK- 50 CLK- PWC+ PWC- MODSET BIASSET V EE -5.2V 2k + + V V MODSET BIASSET - - 330pF 0.1 F REPRESENTS A CONTROLLED- -5.2V IMPEDANCE TRANSMISSION LINE. -5.2V Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.10Gbps EAM Driver with Integrated Bias Network ABSOLUTE MAXIMUM RATINGS Supply Voltage V ..............................................-6.0V to +0.5V Continuous Power Dissipation (T = +85C) EE A Voltage at MODEN, 24-Lead Thin QFN RTEN, PLRT, MODSET, BIASSET ...........(V - 0.5V) to +0.5V (derate 20.8mW/C above +85C).............................1354mW EE Voltage at DATA+, DATA-, CLK+, and CLK--1.65V to +0.5V Storage Temperature Range .....................-55C to +150C Voltage at OUT ..............................................-4V to +0.5V Operating Temperature Range ....................-40C to +85C Voltage at PWC+, PWC- ...................(V - 0.5V) to (V + 1.7V) Lead Temperature (soldering, 10s) .................................+300C EE EE Current Into or Out of OUT................................80mA 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 = -5.5V to -4.9V, T = -40C to +85C. Typical values are at V = -5.2V, I = 30mA, I = 100mA, and T = +25C, unless EE A EE BIAS MOD A otherwise noted.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Power-Supply Voltage V -5.5 -4.9 V EE Retime disabled 124 174 Excluding I and BIAS Supply Current I mA EE I (Note 1) MOD Retime enabled 140 201 Power-Supply Noise Rejection PSNR f 2MHz (Note 2) 15 dB SIGNAL INPUT (Note 3) Input Data Rates NRZ 10.7 Gbps Single-Ended Input Resistance R Input to GND 42.5 50 58.5 IN DC-coupled, Figure 1a -1 0 Single-Ended Input Voltage V V IS AC-coupled, Figure 1b -0.4 +0.4 DC-coupled (Note 4) 0.2 2.0 Differential Input Voltage V V ID P-P AC-coupled (Note 4) 0.2 1.6 Differential Input Return Loss RL 15GHz 15 dB IN EAM BIAS Maximum Bias Current V = V + 2V 50 56 mA BIASSET EE Minimum Bias Current V = V 0.3 1.2 mA BIASSET EE BIASSET Voltage Range V V V + 2 V BIASSET EE EE Equivalent Bias Resistance R (Note 5) 36.4 BSEQV V = V + 0.11V 2.1 4.3 BIASSET EE Bias-Current-Setting Accuracy T = +25C mA V = V + 0.36V 8.8 11.3 A BIASSET EE V = V + 2.0V 52 58.4 BIASSET EE V < V + 0.36V -1100 +1100 Bias-Current Temperature BIASSET EE (Note 6) ppm/C Stability V V + 0.36V -480 +480 BIASSET EE BIASSET Input Resistance 20 k 50 driver load, V = V + 0.55V, BIASSET EE BIASSET Bandwidth 5MHz Figure 2 EAM MODULATION Maximum Modulation Current 112 120 mA P-P Minimum Modulation Current V = V 37 40 mA MODSET EE P-P MODSET Voltage Range V V V + 1 V MODSET EE EE E q uiva l ent M odul at ion Resis tance R (Note 7) 11.1 MODEQV 2 MAX3941