ATA7603 10 Gb/s High Overload TIA PRELIMINARY DATA SHEET - Rev 1.0 FEATURES • • • • • • 1800 Ω Differential Transimpedance 3 mApp Maximum Input Current 14 pA/√Hz Input Noise Current Density Single –5.2 V Power Supply Low Group Delay Outputs DC or AC Coupled GND APPLICATIONS • • • CEXT GND GND IIN VOUT GND VOUT SONET/SDH OC-192 /STM-64 VSR, Short-Reach, Intermediate-Reach, and Long-Reach Receivers 10 Gb/s Ethernet Fiber optic receivers, transceivers, and transponders VEE VEE GND D1 Die PRODUCT DESCRIPTION The ANADIGICS ATA7603 is a –5.2 V high-speed transimpedance amplifier (TIA) designed for 10 Gb/s optical receiver applications available in bare die form and manufactured using an InGaP based HBT process. The device is used in conjunction with a photodetector to convert an optical signal into a differential output voltage that can be AC or DC coupled to a post amplifier. The ATA7603 has an internal overload support circuit and can accept optical inputs as high as +3 dBm. With its low noise and high optical overload capability, the device is well suited for 10 Gb/s Ethernet and OC-192 Very Short-Reach (VSR), Short-Reach, Intermediate-Reach and Long-Reach optical receivers, transceivers and transponders. VBIAS VOUT IIN VOUT VREF DC Offset Control CEXT Low Pass Filter VEE Figure 1: Circuit Block Diagram 06/2002 ATA7603 286 m GND CEXT GND GND 303 m 170 m ATA7603 Die Size: 1000 m x 910 m IIN Die Thickness: 178 m Backside metal thickness: 5 m VOUT Pad Opening: 100 m x 100 m unless otherwise noted GND Pad Pitch 150 m unless otherwise noted VEE VOUT GND VEE 286 m Figure 2: Die Size and Layout Table 1: Pad Description PAD DESCRIPTION COMMENTS V EE -5.2 V Negative Supply Voltage GND Ground IIN 2 TIA Input Photocurrent input CEXT Connection for an External Capacitor Sets the low frequency cutoff VOUT Non-inverted Output Voltage Logical '1' with optical input VOUT Inverted Output Voltage Logical '0' with optical input PRELIMINARY DATA SHEET - Rev 1.0 06/2002 140 m ATA7603 ELECTRICAL CHARACTERISTICS Table 2: Absolute Minimum and Maximum Ratings PARAMETER MIN MAX UNIT DC Power Supply (VEE) -7.0 1.0 V Storage Temperature -65 125 °C - 5.0 mA 100 - V DC Input Current ESD Sensitivity (Human Body Model) Stresses in excess of the absolute ratings may cause permanent damage. Functional operation is not implied under these conditions. Exposure to absolute ratings for extended periods of time may adversely affect reliability. Table 3: Recommended Operating Conditions PARAMETER MIN TYP MAX UNIT Operating Voltage Range -5.50 -5.2 -4.90 V -40 - 85 o C Die Attach Temperature - - 260 o C Photodiode Capacitance (PIN + stray) - 0.225 0.3 pF Photodiode Responsivity - 0.92 - A/W Photodiode Contact Resistance - 10 15 Ω 0.7 1.0 - nH Operating Temperature Range Input Bondwire Inductance The device may be operated safely over these conditions; however, parametric performance is guaranteed only over the conditions defined in the electrical specifications. PRELIMINARY DATA SHEET - Rev 1.0 06/2002 3 ATA7603 Table 4: DC Electrical Specifications MIN TYP MAX UNIT Supply Current (DC Coupled Outputs) - 95 120 mA Input Offset Voltage - -3.7 - V Output Offset Voltage (both ports) - -0.2 - V MIN TYP MAX UNIT 1300 1800 - Ω 8.5 9.5 - GHz - 30 - kHz - - 1.0 dB - 30 - ps - 40 - ps Maximum Input Current - - 3.0 mApp Optical Overload - +3 - dB m - 1.4 - µA - 14 20 pA/√Hz Optical Sensitivity (4) - -19 - dB m Maximum Single-ended Output Voltage Swing - 400 - mVpp Output Return Loss (10 MHz to 8 GHz) - - -10 dB Output Return Loss (8 MHz to 20 GHz) - - -5 dB PARAMETER Table 5: AC Electrical Specifications (1) PARAMETER Small Signal Differential Transimpedance (RL = 100 Ω) Small Signal Bandwidth Low Frequency Cutoff (2) Peaking Group Delay Deviation (500 MHz to 8.0 GHz) Group Delay Deviation (8 GHz to 9.5 GHz) (3) (3) (4) Input Referred RMS Noise Current (5) Average Input Referred Noise Current Density (5) Notes: (1) The specifications are based upon the use of a PIN photodiode with a responsivity of 0.92 A/W and a capacitance of CDIODE + CSTRAY = 0.3 pF max connected to IIN via a 1.0 nH bond wire. (2) With the use of an external 10 nF capacitor. (3) Maximum value - minimum value (4) Measured at 10-10 BER with a 223 -1 PRBS at 10 Gb/s (5) Bandwidth = 9 GHz 4 PRELIMINARY DATA SHEET - Rev 1.0 06/2002 ATA7603 PERFORMANCE DATA Figure 3: Typical Small Signal Frequency Response Figure 4: Typical Small Signal Group Delay 27.2 320 3 dB Bandwidth = 9.9 GHz 300 Group Delay (ps) Response(dB) 24.2 21.2 18.2 280 260 240 220 200 15.2 0 2 4 6 8 Frequency(GHz) 10 180 12 0 4 6 8 10 12 Frequency(GHz) Figure 6: Differential Transimpedance vs. Input Current Figure 5: Bandwidth vs. Input Inductance 65 3.000 64 2.500 63 2.000 Vee=-5.2V VEE=-4.9V Tz (Kohms) VEE=-5.5V 62 61 Gain (dB) 2 1.500 1.000 60 Lin = 30mils, BW = 9.3GHz 59 Lin = 35mils, BW = 9.6GHz 0.500 0.000 Lin = 40mils, BW = 9.9GHz 58 10 100 Lin = 45mils, BW = 10.6GHz 57 Lin = 50mils, BW = 10.9GHz 56 Lin = 55mils, BW = 11.1GHz 1000 10000 Input Current (uApp) Lin = 60mils, BW = 11.1GHz 55 0 2 4 6 8 10 12 Frequency (GHz) Figure 8: Differential Output Voltage vs. Input Current up to 4000 App 900 900 800 800 700 700 Output Voltage (mVpp) Output Voltage (mVpp) Figure 7: Differential Output Voltage vs. Input Current up to 1000 App 600 500 400 300 200 VEE=-5.2V 600 500 400 300 200 VEE=-5.2V VEE=-4.9V 100 VEE=-4.9V 100 VEE=-5.5V VEE=-5.5V 0 0 200 400 600 Input Current (uApp) 800 1000 0 0 500 1000 1500 2000 2500 3000 3500 4000 Input Current (uApp) PRELIMINARY DATA SHEET - Rev 1.0 06/2002 5 ATA7603 Figure 9: Eye Diagram with an Optical Input Power of -18 dBm Figure 10: Eye Diagram with an Optical Input Power of -10 dBm Figure 11: Eye Diagram with an Optical Input Power of 0 dBm Figure 12: Eye Diagram with an Optical Input Power of +3 dBm Figure 13: Eye Diagram with an Optical Input Power of +4 dBm Figure 14: S22 from Evaluation Test Fixture 0 -5 S22 (dB) -10 -15 -20 -25 -30 -35 -40 0 2 4 6 8 10 12 Frequency (GHz) 6 PRELIMINARY DATA SHEET - Rev 1.0 06/2002 14 16 18 20 ATA7603 APPLICATION INFORMATION Ceramic substrate CEXT 10nF 2 nH typical Ground pads 1.0 nH typical VOUT (50 ) 470 pF Photodiode ATA7603 470 pF VOUT (50 ) Kovar pedestal 220 pF VEE bypass MIM capacitor 10 nF VBIAS All die bonds are 0.5 nH typical unless otherwise noted VEE Figure 15: Bonding Diagram PRELIMINARY DATA SHEET - Rev 1.0 06/2002 7 ATA7603 PACKAGING The ATA7603 is provided as bare die. For optimum performance, the die should be packaged in a hermetic enclosure and a low inductance ground plane should be made available for power supply bypassing and ground bonds. When packaging the ATA7603, the temperature of the die must be kept below 260 °C to ensure device reliability. The ATA7603 has backside metal but no ground vias are connected to the backside of the die, so it is critical to bond all of the ground pads to reduce ground inductance. The die can be attached to the substrate using epoxy or solder. A good thermally conductive, silver-filled epoxy is recommended for epoxy mounting. If solder is used for die attach, exposure to temperatures at or above 260 °C must be limited to ensure the device reliability. A soft silicon/rubber tip collet should be used for die mounting, although tweezers can be used with extreme care. Thermosonic ball bonding, at a stage temperature of 150 to 175 °C, with 1 to 1.3 mil gold wire, is the recommended interconnect technique. The bond force, time, and ultrasonic power are all critical parameters and should be optimized to achieve the best bonding performance. The recommended bonding parameters are: Stage Temperature: 175 °C Bond Time: 15 ms Bond Ultrasonic Power: 70 mW Bond Force: 70 g Bond Velocity: 60 mils/ms 8 IIN Connection For optimal performance, the bond wire from the photodetector to IIN should be around 1nH. As the inductance of this connection increases beyond 1nH, more gain peaking will occur and the group delay performance will degrade. VEE Connections In order to achieve optimal performance, the VEE supply pads must be bypassed as close to the chip as possible with one or two high resonant frequency, low value capacitance, MIM capacitors. In either case, both V EE bond pads need to be connected to reduce the supply bond wire inductance. VOUT and VOUT Connections The ATA7603 provides a differential output that can be AC or DC coupled to the next stage of the receiver. The output bond wires should be kept below 1 nH for the best performance. If the device is being used in a single-ended configuration, the unused output port must be terminated into 50 Ω. CEXT Connection In order to achieve the desired low frequency cutoff, an external capacitor is required. A low inductance multilayer chip capacitor of value 10 nF is recommended. PRELIMINARY DATA SHEET - Rev 1.0 06/2002 ATA7603 TYPICAL APPLICATION CIRCUITS 100 nF VBIAS VOUT VIN (1) VIN (1) DCOUT DCOUT VOUT IIN CEXT VEE VOUT VEEOS ATA7603 10 nF VOUT VEE ALA7606 VEE VEE VEE 50 50 Figure 16: ATA7603 DC Coupled to the ALA7606 100 nF VBIAS VOUT VIN (1) VIN (1) DCOUT DCOUT VOUT IIN CEXT VEE VOUT VEEOS ATA7603 10 nF VEE VOUT VEE ALA7606 VEE VEE 50 50 Figure 17: ATA7603 AC Coupled to the ALA7606 Notes: (1) The ALA7606 is a non-inverting amplifier and VIN and VIN can be interchanged. PRELIMINARY DATA SHEET - Rev 1.0 06/2002 9 ATA7603 NOTES 10 PRELIMINARY DATA SHEET - Rev 1.0 06/2002 ATA7603 NOTES PRELIMINARY DATA SHEET - Rev 1.0 06/2002 11 ATA7603 ORDERING INFORMATION ORDER NUMBER TEMPERATURE RANGE PACKAGE DESCRIPTION COMPONENT PACKAGING ATA7603D1 -40 oC to +85 oC D1 Die ANADIGICS, Inc. 141 Mount Bethel Road Warren, New Jersey 07059, U.S.A. Tel: +1 (908) 668-5000 Fax: +1 (908) 668-5132 URL: http://www.anadigics.com E-mail: [email protected] IMPORTANT NOTICE ANADIGICS, Inc. reserves the right to make changes to its products or to discontinue any product at any time without notice. The product specifications contained in Advanced Product Information sheets and Preliminary Data Sheets are subject to change prior to a product’s formal introduction. Information in Data Sheets have been carefully checked and are assumed to be reliable; however, ANADIGICS assumes no responsibilities for inaccuracies. ANADIGICS strongly urges customers to verify that the information they are using is current before placing orders. WARNING ANADIGICS products are not intended for use in life support appliances, devices or systems. Use of an ANADIGICS product in any such application without written consent is prohibited. 12 PRELIMINARY DATA SHEET - Rev 1.0 06/2002