19-2699; Rev 0; 2/03 DC-Coupled, UCSP 3.125Gbps Equalizer Features ♦ DC-Coupled Input and Output to Terminations as Low as +1.1V ♦ 2mm × 2.5mm UCSPTM ♦ 1Gbps to 3.2Gbps Operating Range ♦ Spans 40in (1m) of FR4 ♦ Spans 10m, 28AWG Twin Ax ♦ Receive Equalization to Reduce ISI Applications Backplane Interconnect Ordering Information Rack-to-Rack Interconnect Common-Mode Voltage Translation (LVDS, PECL, or CML) PART TEMP RANGE MAX3803UBP-T 0°C to +85°C PIN-PACKAGE 5 x 4 UCSP Pin Configuration appears at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. Typical Application Circuit LINE CARD SWITCH CARD +1.1V ≤ V ≤ VCC +1.1V ≤ V ≤ VCC +3.3V MAC WITH SERDES ≤40in (1m) 2 2 FR4 STRIPLINE Tx IN +3.3V VCC 2 Tx Rx 2 MAX3803 2 OUT MAX3803 VTO +1.1V ≤ V ≤ VCC VCC SWITCH ASIC WITH SERDES VTO 2 2 OUT Rx PC BOARD BACKPLANE Rx VTI IN 2 FR4 STRIPLINE Tx VTI +1.1V ≤ V ≤ VCC ________________________________________________________________ Maxim Integrated Products 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. 1 MAX3803 General Description The MAX3803 equalizer automatically provides compensation for transmission-medium losses encountered with FR4 stripline and cable in an incredibly small 2mm × 2.5mm package. It is ideal for backplane applications requiring up to 40in between the line card and the switch card or up to 10m of twin ax cable between racks. Its small size provides placement and routing flexibility. The CML inputs and outputs are DC-coupled and can be terminated to a supply as low as +1.1V. The MAX3803 operates from 0°C to +85°C and consumes 160mW at +3.3V. MAX3803 DC-Coupled, UCSP 3.125Gbps Equalizer ABSOLUTE MAXIMUM RATINGS Supply Voltage, VCC, VTI, and VTO ..........................-0.5V to +6V Continuous Output Current ...............................-25mA to +25mA IN±, OUT±, EN............................................-0.5V to (VCC + 0.5V) Operating Ambient Temperature Range ................0°C to +85°C Storage Ambient Temperature Range...............-55°C to +150°C 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. OPERATING CONDITIONS PARAMETER SYMBOL CONDITIONS MIN TYP 3.3 MAX UNITS Supply Voltage VCC 3.0 3.6 V Input Termination Voltage VTI 1.1 VCC V Output Termination Voltage VTO 1.1 VCC V Supply Noise Tolerance 10Hz ≤ f < 100Hz 100 100Hz ≤ f < 1MHz 40 1MHz ≤ f ≤ 2.5GHz 10 Operating Ambient Temperature 0 Bit Rate NRZ data CID Consecutive identical digits 25 2.488 mVP-P 85 °C 3.125 Gbps 100 bits ELECTRICAL CHARACTERISTICS (Typical values are at +3.3V and at TA = +25°C, unless otherwise noted. Specifications guaranteed over specified operating conditions.) PARAMETER SYMBOL Supply Current (Note 1) TYP MAX EN = high CONDITIONS MIN 45 65 EN = low 14 30 Output Driver Supply Current (Note 2) Input Swing (Note 1) Measured differentially at point A (Figure 1) Input Common-Mode Voltage Range (Note 1) Input Return Loss 100MHz to 2.5GHz Input Resistance Single ended (Note 1) 42.5 50 57.5 EN = high 400 450 600 Output Swing (Notes 1, 3) 9 14 mA 1000 mVP-P VTI 0.25V VTI 0.10V V 10 VTO 0.112V Single ended (Note 1) 100MHz to 2.5GHz Output Transition Time Differential Skew 2 dB 30 Output Common-Mode Voltage Output Return Loss tr, tf 20% to 80% (Notes 2, 4) Difference in 50% crossing between OUT+ and OUT- mA 400 EN = low Output Resistance UNITS 42.5 50 70 10 _______________________________________________________________________________________ mVP-P V 57.5 10 40 Ω Ω dB 100 ps ps DC-Coupled, UCSP 3.125Gbps Equalizer (Typical values are at +3.3V and at TA = +25°C, unless otherwise noted. Specifications guaranteed over specified operating conditions.) PARAMETER SYMBOL Residual Deterministic Jitter Output (2.5Gbps, CJTPAT) (Notes 2, 5) Residual Deterministic Jitter Output (2.5Gbps, 27 PRBS + 100 CID) (Notes 2, 6) Residual Deterministic Jitter Output (3.125Gbps, CJTPAT) (Notes 2, 7) CONDITIONS MIN TYP MAX 0in, 6-mil FR4 0.01 0.10 10in, 6-mil FR4 0.04 0.10 20in, 6-mil FR4 0.05 0.10 30in, 6-mil FR4 0.05 0.15 40in, 6-mil FR4 0.07 0.15 3m Tensolite cable 0.03 0.10 5m Tensolite cable 0.1 0.20 10m Tensolite cable 0.14 0.25 0in, 6-mil FR4 0.01 0.10 10in, 6-mil FR4 0.06 0.10 20in, 6-mil FR4 0.11 0.15 30in, 6-mil FR4 0.15 0.20 3m Tensolite cable 0.09 0.15 0in, 6-mil FR4 0.01 0.10 10in, 6-mil FR4 0.02 0.10 20in, 6-mil FR4 0.03 0.15 30in, 6-mil FR4 0.06 0.15 40in, 6-mil FR4 0.11 0.25 3m Tensolite cable 0.05 0.10 5m Tensolite cable 0.16 0.25 2 3 Random Jitter Output (Notes 2, 4) Latency From IN to OUT Low-Frequency Cutoff UNITS UI UI UI psRMS 0.3 ns 15 kHz LVTTL Input High Voltage VIH (Note 1) 1.5 LVTTL Input Low Voltage VIL (Note 1) 0.5 V V LVTTL Input High Current IIH (Note 1) 10 µA LVTTL Input Low Current IIL (Note 1) 10 µA Production tested at TA = +25°C. Specifications over temperature are guaranteed by design and characterization. Specifications are guaranteed by design and characterization. Measured differentially at point C with 50Ω ±1% at each side (Figure 1). Using a 0000011111 or equivalent pattern at selected bit rate. Measured at 600mVP-P input voltage, 10m cable or 40in FR4, at 2.5Gbps and within 2in of output pins. Note 5: Difference in peak-to-peak deterministic jitter between reference points A and C in Figure 1. Evaluated at 2.5Gbps with CJTPAT. Note 6: Difference in peak-to-peak deterministic jitter between reference points A and C in Figure 1. Evaluated at 2.5Gbps with a PRBS 27 with 100 CIDs input pattern. Note 7: Difference in peak-to-peak deterministic jitter between reference points A and C in Figure 1. Evaluated at 3.125Gbps with CJTPAT. Note 1: Note 2: Note 3: Note 4: _______________________________________________________________________________________ 3 MAX3803 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VCC = +3.3V, VTI = +1.1V, VTO = +1.1V, and TA = +25°C, unless otherwise noted.) MAX3803 toc02 MAX3803 toc01 150mV/div 150mV/div 150mV/div 680ps/div 100ps/div 100ps/div RANDOM JITTER vs. LENGTH (IN± = 800mVP-P, PATTERN = K28.7) RANDOM JITTER vs. LENGTH (IN± = 400mVP-P, PATTERN = K28.7) RANDOM JITTER (psRMS) 80 70 60 50 40 30 5 4 RANDOM JITTER (psRMS) 90 MAX3803 toc05 5 MAX3803 toc04 100 2.48832Gbps 3 3.125Gbps 2 MAX3803 toc06 SUPPLY CURRENT vs. AMBIENT TEMPERATURE SUPPLY CURRENT (mA) MAX3803 toc03 40in, 6-mil FR4 AT 3.125Gbps WITH CJTPAT 20ft TENSOLITE CABLE AT 2.48832Gbps WITH PRBS 223 - 1 30in, 6-mil FR4 AT 3.125Gbps WITH K28.5 (BEFORE EQUALIZATION, AFTER EQUALIZATION) (BEFORE EQUALIZATION, AFTER EQUALIZATION) (BEFORE EQUALIZATION, AFTER EQUALIZATION) 4 3 2.48832Gbps 2 20 10 3.125Gbps 1 1 0 0 10 20 30 40 50 60 70 0 80 10 20 30 40 0 50 10 20 30 50 40 AMBIENT TEMPERATURE (°C) LENGTH OF 6-mil FR4 STRIPLINE (in) LENGTH OF 6-mil FR4 STRIPLINE (in) RANDOM JITTER vs. INPUT AMPLITUDE (40in, 6-mil FR4 STRIPLINE, PATTERN = K28.7) DETERMINISTIC JITTER vs. BIT RATE (30in, 6-mil FR4 STRIPLINE, IN± = 1000mVP-P) DETERMINISTIC JITTER vs. BIT RATE (33ft, 28AWG TENSOLITE CABLE, IN± = 400mVP-P) 2.48832Gbps 3 2 PRBS 210 - 1 60 PRBS 27 - 1 50 40 CJTPAT PRBS 210 - 1 90 80 PRBS 27 - 1 70 CJTPAT 60 K28.5 50 30 3.125Gbps MAX3803 toc09 MAX3803 toc08 70 100 DETERMINISTIC JITTER (ps) 4 80 DETERMINISTIC JITTER (ps) MAX3803 toc07 5 RANDOM JITTER (psRMS) MAX3803 DC-Coupled, UCSP 3.125Gbps Equalizer K28.5 400 500 600 700 800 INPUT AMPLITUDE (mVP-P) 4 40 20 1 900 1000 2.0 2.3 2.6 2.9 BIT RATE (Gbps) 3.2 3.5 2.0 2.3 2.6 2.9 BIT RATE (Gbps) _______________________________________________________________________________________ 3.2 3.5 DC-Coupled, UCSP 3.125Gbps Equalizer 90 50 45 40 35 K28.5 30 70 PRBS 27 WITH 100CIDs 60 50 40 65 DETERMINISTIC JITTER (ps) 80 DETERMINISTIC JITTER (ps) CJTPAT 7 PRBS 2 - 1 25 20 600 700 800 900 1000 50 1.25Gbps 400 500 INPUT AMPLITUDE (mVP-P) 600 700 800 900 400 1000 INPUT AMPLITUDE (mVP-P) 90 80 622.08Mbps 70 60 50 2.48832Gbps 40 80 70 DETERMINISTIC JITTER (ps) MAX3803 toc13 100 600 700 800 900 1000 INPUT AMPLITUDE (mVP-P) DETERMINISTIC JITTER vs. LENGTH (IN± = 600mVP-P, PATTERN = CJTPAT) DETERMINISTIC JITTER vs. LENGTH (IN± = 800mVP-P, PATTERN = PRBS 210 - 1) 110 500 MAX3803 toc14 500 3.125Gbps 55 40 20 400 60 45 30 DETERMINISTIC JITTER (ps) DETERMINISTIC JITTER (ps) 55 70 MAX3803 toc12 60 DETERMINISTIC JITTER vs. INPUT AMPLITUDE (33ft, 28AWG TENSOLITE CABLE, PATTERN = K28.5) MAX3803 toc11 DETERMINISTIC JITTER vs. INPUT AMPLITUDE (30in, 6-mil FR4 STRIPLINE, 2.488Gbps) MAX3803 toc10 DETERMINISTIC JITTER vs. INPUT AMPLITUDE (40in, 6-mil FR4 STRIPLINE, 3.125Gbps) 30 60 50 1.25Gbps 40 3.125Gbps 30 20 20 10 10 0 10 20 30 40 50 LENGTH OF 6-mil FR4 STRIPLINE (in) 0 10 20 30 40 50 LENGTH OF 6-mil FR4 STRIPLINE (in) Pin Description PIN NAME FUNCTION A1 VTO Output Termination Voltage A2 EN Enable. Connect to VCC to enable the equalizer core. Connect to GND to disable the equalizer core, TTL. Do not leave unconnected. A3, A4 N.C. A5 VTI Input Termination Voltage B1 OUT+ Positive Data Output, CML No Connection B5 IN+ C1 OUT- Positive Data Input, CML C5 IN- D1, D5 GND Supply Ground D2, D3, D4 VCC Core Supply Voltage Negative Data Output, CML Negative Data Input, CML _______________________________________________________________________________________ 5 MAX3803 Typical Operating Characteristics (continued) (VCC = +3.3V, VTI = +1.1V, VTO = +1.1V, and TA = +25°C, unless otherwise noted.) MAX3803 DC-Coupled, UCSP 3.125Gbps Equalizer _______________Detailed Description ______and Applications Information The MAX3803 is an adaptive equalizer designed to extend the reach of transmission lines in high-frequency backplane and rack-to-rack interconnect applications. The MAX3803 automatically adjusts to attenuation caused by skin-effect and dielectric losses. Although optimized for coded and scrambled data between 2.488Gbps and 3.125Gbps, the MAX3803 provides effective compensation for rates between 1Gbps and 3.2Gbps. Media Equalization Equalization at the input compensates for high-frequency loss encountered with FR4 stripline (edge-coupled) or 28AWG twin ax. The equalizer core is an amplifier with a self-adjusting frequency response. DC Cancellation Loop The DC cancellation loop removes the pulse-width distortion caused by internal offsets. The closed-loop response creates a low-frequency cutoff of approximately 15kHz, below which the offset control tracks the AC signal. This also sets the limit on the maximum time The MAX3803 consists of low common-mode input and output buffers, an equalizer core, a DC-offset-correction loop, and a limiting amplifier (Figure 2). +1.1V ≤ VTI ≤ VCC VCC VCC Low Common-Mode Input and Output The MAX3803 permits DC-coupling to CML transmitters and receivers that require termination voltages as low as 1.1V and as high as VCC. Use the VTI and VTO pins to maintain compatible common-mode levels between the data source and load. VTI and VTO are independent and can be used to bridge two common-mode requirements without the use of DC-blocking capacitors. See Figure 3 and Figure 4 for the equivalent input and output structures. A SIGNAL SOURCE B 2 CONNECTOR 2 CONNECTOR MAX3803 2 IN- CML INPUT EQUALIZER VCC INESD STRUCTURES OUT +1.1V ≤ VTO ≤ VCC 50Ω Figure 1. Backplane Interconnect IN+ IN+ Figure 3. CML Input Structure 2 ≤40in EDGE-COUPLED TRANSMISSION LINE ON FR4 OR ≤10m 28AWG TWIN AX CABLE VCC 50Ω C IN VTI 50Ω VCC 50Ω OUT+ OUT- VTO LIMITING AMPLIFER CML OUTPUT OUT+ ESD STRUCTURES OUT- DC CANCELLATION LOOP MAX3803 Figure 2. Functional Diagram 6 Figure 4. CML Output Structure _______________________________________________________________________________________ DC-Coupled, UCSP 3.125Gbps Equalizer Limiting Amplifier TOP VIEW The limiting amplifier limits the outputs of the equalizer so all frequencies are at the same output voltage level. Enable Function Connect the EN pin to VCC to enable the equalizer core. Connect the EN pin to GND to disable the equalizer core when valid data is not present to save power. When EN is low, the outputs are static with approximately 30mVP-P differential. This pin must be connected to VCC or GND. 2 3 4 5 VTO EN N.C. N.C. VTI A B OUT+ IN+ MAX3803 C Packaging The MAX3803 is packaged in a 2.5mm × 2mm, 5 × 4 chip-scale package (USCP). The six center ball positions (B2, B3, B4, C2, C3, C4) are not populated, leaving fourteen perimeter balls. This package does not require underfill over an ambient temperature range of 0°C to +85°C. Thermal dissipation is provided through the GND connection. Go to Maxim’s website, www.maximic.com, for the latest packaging information and details about UCSP layout and handling. 1 OUT- IN- D GND VCC VCC VCC GND UCSP 2.5mm × 2mm Layout Techniques For best performance, use good high-frequency layout techniques. Filter voltage supplies, keep ground connections short, and use multiple vias where possible. Use controlled-impedance transmission lines to interface with the MAX3803 high-speed inputs and outputs. Power-supply decoupling should be placed as close to the VCC as possible. To reduce feedthrough, isolate input signals from output signals. _______________________________________________________________________________________ 7 MAX3803 Pin Configuration required to reach a balanced mark/space ratio (i.e., 50%). This permits the use of scrambled data as found in SONET and SDH transmissions. Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) 5x4 UCSP.EPS MAX3803 DC-Coupled, UCSP 3.125Gbps Equalizer Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2003 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.