SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Applications § § § Product Description SONET/SDH-based transmission systems, test equipment and modules OC-3 fibre optic modules and line termination ATM and FDDI optical receivers SiGe Semiconductor offers a portfolio of optical networking ICs for use in high-performance optical transmitter and receiver functions, from 155 Mb/s up to 12.5 Gb/s. SiGe Semiconductor’s SE1000W is a fully integrated, silicon bipolar transimpedance amplifier; providing wideband, low noise preamplification of signal current from a photodetector. It features single-ended or differential outputs, selectable by wire bond options, and incorporates an automatic gain control mechanism to increase dynamic range, allowing input signals up to 2.6 mA peak. For differential outputs, a decoupling capacitor on the supply is the only external circuitry required. Features § § § § § § § § § § § Single +5 V power supply Input noise current = 12 nA rms when used with a 0.5 pF detector Transimpedance gain = 15 kΩ into a 50 Ω load (single-ended) On-chip automatic gain control gives input current overload of 2.6 mA pk and max output voltage swing of 300 mV pk-pk 50 Ω single-ended or 100 Ω differential wire bond selectable outputs Bandwidth (-3 dB) = 150 MHz (min) Wide data rate range = 10 Mb/s to 155 Mb/s High input bias level = 2 V Minimal external components, supply decoupling only Operating junction temperature range = -40°C to +95°C Equivalent to Nortel Networks AB52 Noise performance is optimized for 155 Mb/s operation, with a calculated rms noise based -10 sensitivity of –41 dBm for 10 bit error rate, achieved using a detector with 0.5 pF capacitance and a responsivity of 0.95 A/W, with an infinite extinction ratio source. Ordering Information Type SE1000W Package Bare Die Remark Shipped in Waffle Pack Functional Block Diagram Automatic Gain Control SE1000 TzAmp 155 Mb/s Integrator Rectifier 50 Ω Rf TZ_IN Input Current Tz Amp Output Driver OUTP 50 Ω OUTN 50 Ω Bandgap Reference GND or –ve supply 40-DST-01 § Rev 1.5 § May 24/02 Power Supply Rejection ACGND Wire bond option for single-ended operation 1 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Bondpad Diagram VCC2 1 VCC1 2 10 VCC1 9 OUTP 8 OUTN Top View TZ_IN 3 4 5 VEE2 ACGND 6 VEE1 7 VEE1 Bondpad Description Pad No. Name Description 1 VCC2 Positive supply (+5.0 V), front end circuitry only. 2 VCC1 3 TZ_IN Positive supply (+5.0 V), pads 2 & 10 are connected on chip. Only one pad needs to be bonded. Input pad (connect to photodetector cathode). 4 VEE2 5 ACGND 6 VEE1 7 VEE1 8 OUTN Negative supply (0V) – Note this is separate ground for the input stage, which is AC coupled on chip. There is no DC current through this pad. Bond option: Connected to external capacitor to ground for single-ended operation (recommended 1 nF); unconnected for differential operation. Negative supply (0V), pads 6 & 7are connected on chip. Only one pad needs to be bonded. Negative supply (0V), pads 6 & 7 are connected on chip. Only one pad needs to be bonded. Negative differential voltage output; leave unconnected for single-ended operation. 9 OUTP Positive differential or single-ended voltage output. 10 VCC1 Positive supply (+5.0 V), pads 2 & 10 are connected on chip. Only one pad needs to be bonded. 40-DST-01 § Rev 1.5 § May 24/02 2 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Functional Description Amplifier Front-End The transimpedance front-end amplifies an input current from a photodetector, at pin TZ_IN, to produce an output voltage with the feedback resistor Rf determining the level of amplification (see the functional block diagram on page 1). An automatic gain control loop varies this resistor, to ensure that the output from the front-end does not saturate the output driver stage that follows. This gain control allows input signals of up to 2.6 mA peak. The input pin TZ_IN is biased at 3 V below the supply voltage VCC, allowing a photodetector to easily be reverse biased by connecting the anode to ground, and hence enabling s ingle rail operation. to ground (recommend 1 nF). Under these circumstances, OUTP operates as a single-ended 50 Ω output. In both cases, increasing optical input level gives a positive-going output signal on the OUTP pin. Automatic Gain Control (AGC) The AGC circuit monitors the voltages from the output driver and compares them to an internal reference level produced via the on-chip bandgap reference circuit. When this level is exceeded, the gain of the front-end is reduced by controlling the feedback resistor Rf. A long time-constant integrator is used within the control loop of the AGC with a typical low frequency cut-off of 5 kHz. The front-end stage has its own supply pins, VCC2 (+5 V) and VEE2 (0 V), to achieve optimum noise performance and maintain integrity of the high-speed signal path. The remainder of the circuitry uses the supply pins VCC1 (+5 V) and VEE1 (0 V). Power Supply Rejection Output driver stage This stable DC reference minimizes the variation in the noise and bandwidth performance of the circuit due to power supply variation of +4.7 V to +5.3 V. The output driver acts as a buffer stage, capable of swinging up to 150 mVpk-pk into a 50 Ω load (or 300 mVpk-pk differential into a 100 Ω load). The small output swings allow ease of use with low voltage post amplifiers (e.g. 3.3 V parts). The output can be configured in a differential or single-ended mode. For differential operation, the pad ACGND is not wire bonded and the circuit provides a fully balanced 100 Ω output, on the pins OUTP and OUTN. For single-ended operation, the ACGND pad is required to be wire bonded to an external capacitor 40-DST-01 § Rev 1.5 § May 24/02 An on-chip power supply rejection circuit is used to achieve both single-ended and differential rejection from the +5 V VCC rail. The AC rejection ensures that performance is not degraded by noise on the power supply. The circuit achieves a power supply rejection on the outputs of 40 dB for both single-ended and differential operation, up to 100 kHz. The use of external decoupling will help to remove any unwanted signals at higher frequencies. 3 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Absolute Maximum Ratings These are stress ratings only. Exposure to stresses beyond these maximum ratings may cause permanent damage to, or affect the reliability of the device. Avoid operating the device outside the recommended operating conditions defined below. Symbol Parameter Min Max Unit VCC Supply Voltage –0.7 6.0 V VIO Voltage at any input or output –0.5 VCC+0.5 V IIO Current sourced into any input or output except TZ_IN –20 20 mA IIO Current sourced into pin TZ_IN –5 5 mA VESD Electrostatic Discharge (100 pF, 1.5 kΩ) except TZ_IN –2 2 kV VESD Electrostatic Discharge (100 pF, 1.5 kΩ) pin TZ_IN –0.25 0.25 kV Tstg Storage Temperature –65 150 °C Recommended Operating Conditions Symbol Parameter Min Typ Max Unit 5.0 5.3 V 95 °C Typ Max Unit 39 58 mA VCC Supply Voltage 4.7 Tj Operating Junction Temperature –40 DC Electrical Characteristics Symbol Parameter Min ICC Supply Current lagc AGC Threshold Vin Input Bias Voltage Vout Output Bias Voltage 2.9 Rout Output Resistance 35 40-DST-01 § Rev 1.5 § May 24/02 µA pk-pk 4 VCC–3.2 VCC–3.0 50 VCC–2.7 V 3.5 V 65 Ω 4 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final AC Electrical Characteristics Symbol Parameter Min Typ Max 150 Unit BW (3dB) Small Signal Bandwidth at –3dB point MHz Tz Single-ended Transimpedance (50 Ω on output, f = 50 MHz) 11 Dri Input Data Rate 10 Voutmax Maximum Differential Output Voltage Flf Low Frequency Cut-off 5 kHz PSRR Power Supply Rejection Ratio (single-ended or differential) up to 100 kHz 40 dB lOL Input Current before overload (155 Mb/s NRZ data) 2600 µA pk-pk Pol Optical Overload +1.4 dBm Nrms Input Noise Current (in 100 MHz) 15 12 20 kΩ 155 Mb/s 300 mV pk-pk 15 nA rms DC and AC electrical characteristics are specified under the following conditions : Supply Voltage (VCC).........................................4.7 V to 5.3 V Junction Temperature (Tj)..................................–40°C to 95°C Load Resistor (RL)...............................................50 Ω AC coupled via 220 nF (single-ended) Photodetector Capacitance (Cd).......................0.5 pF Input bond wire inductance................................1 nH Photodetector responsivity.................................0.95 A/W Transimpedance (Tz) measured with 1 µA mean photocurrent 40-DST-01 § Rev 1.5 § May 24/02 5 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Bondpad Configuration The bondpad center coordinates are referenced to the center of the lower left pad (pad 4). All dimensions are in microns (µm). Pad No. Name X Coordinate (µm) Y Coordinate (µm) 1 VCC2 -307.3 679.0 2 VCC1 -307.3 549.0 3 TZ_IN -307.3 315.0 4 VEE2 0 0 5 ACGND 130.0 0 6 VEE1 260.0 0 7 VEE1 390.0 0 8 OUTN 690.7 155.0 9 OUTP 690.7 285.0 10 VCC1 690.7 679.0 40-DST-01 § Rev 1.5 § May 24/02 6 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final The diagram below shows the bondpad configuration of the SE1000W Transimpedance Amplifier. Note that the diagram is not to scale. All bondpads are 92 µm x 92 µm with a passivation opening of 82 µm x 82 µm. There are two VCC1 and two VEE1 pads for ease of wire bonding; these pad pairs are connected on-chip and only one pad of each type is required to be bonded out. Mechanical die visual inspection criteria per MIL-STD-883 Method 2010.10 Condition B Class Level B. 394.0 Top View 130.0 130.0 130.0 307.3 155.0 130.0 126.0 315.0 925.0 234.0 130.0 998.0 300.7 123.0 Side View 400.0 1250.0 All Dimensions in Microns (µm) 40-DST-01 § Rev 1.5 § May 24/02 7 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final Applications Information For optimum performance it is recommended that the device be used in differential mode with the circuit shown in the first diagram below. Note that the two VCC1 pads (2, 10) are connected on-chip, as are the VEE1 pads (6, 7), and only one pad of each type is required to be bonded out. However, in order to minimize inductance for optimum high speed performance, it is recommended that all power pads are wire bonded. The VEE2 and VCC2 pads are not connected on chip to VEE1 and VCC1 respectively, and must be bonded out separately. Connections for differential operation: +5 V 1 VCC2 3 VEE2 4 1 nF min 10 VCC1 TZ Amplifier SE1000W TZ_IN PIN 2 VEE1 6 7 9 OUTP OUTN 8 To 50 O loads, AC coupled ACGND 5 NC 0 V or –ve bias 0V Connections for single-ended operation: +5 V 1 VCC2 3 VEE2 4 1 nF min 10 VCC1 TZ Amplifier SE1000W TZ_IN PIN 2 VEE1 6 7 9 To 50 O load, AC coupled OUTP OUTN 8 NC ACGND 5 1 nF 0 V or –ve bias 0V 40-DST-01 § Rev 1.5 § May 24/02 8 of 9 SE1000W LightChargerTM155 Mb/s Transimpedance Amplifier Final http://www.sige.com Headquarters: Canada Phone: +1 613 820 9244 Fax: +1 613 820 4933 2680 Queensview Drive Ottawa ON K2B 8J9 Canada [email protected] U.S.A. United Kingdom 1150 North First Street San Jose, CA USA 95112 1010 Cambourne Business Park Cambourne Cambridge CB3 6DP Phone: +1 408 998 5060 Fax: +1 408 998 5062 Phone: +44 1223 598 444 Fax: +44 1223 598 035 Product Preview The datasheet contains information from the product concept specification. SiGe Semiconductor reserves the right to change information at any time without notification. Preliminary The datasheet contains information from the design target specification. SiGe Semiconductor reserves the right to change information at any time without notification. Final The datasheet contains information from the final product specification. SiGe Semiconductor reserves the right to change information at any time without notification. Production testing may not include testing of all parameters. Information furnished is believed to be accurate and reliable and is provided on an “as is” basis. SiGe Semiconductor Inc. assumes no responsibility or liability for the direct or indirect consequences of use of such information nor for any infringement of patents or other rights of third parties, which may result from its use. No license or indemnity is granted by implication or otherwise under any patent or other intellectual property rights of SiGe Semiconductor Inc. or third parties. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. SiGe Semiconductor Inc. products are NOT authorized for use in implantation or life support applications or systems without express written approval from SiGe Semiconductor Inc. LightCharger™ is a trademark owned by SiGe Semiconductor. Copyright 2002 SiGe Semiconductor All Rights Reserved 40-DST-01 § Rev 1.5 § May 24/02 9 of 9