19-2834; Rev 2; 2/04 155Mbps Low-Noise Transimpedance Amplifier The MAX3657 is a transimpedance preamplifier for receivers operating up to 155Mbps. The low noise, high gain, and low-power dissipation make it ideal for Class-B and Class-C passive optical networks (PONs). The circuit features 14nA input-referred noise, 130MHz bandwidth, and 2mA input overload. Low jitter is achieved without external compensation capacitors. Operating from a +3.3V supply, the MAX3657 consumes only 76mW power. An integrated filter resistor provides positive bias for the photodiode. These features, combined with a small die size, allow easy assembly into a TO-46 header with a photodiode. The MAX3657 includes an average photocurrent monitor. The MAX3657 has a typical optical sensitivity of -38dBm (0.9A/W), which exceeds the Class-C PON requirements. Typical overload is 0dBm. The MAX3657 is available in die form with both output polarities (MAX3657E/D and MAX3657BE/D.) The MAX3657 is also available in a 12-pin, 3mm x 3mm thin QFN package. Applications Optical Receivers (Up to 155Mbps Operation) Passive Optical Networks (PONs) Features ♦ 14nARMS Input-Referred Noise ♦ 54kΩ Transimpedance Gain ♦ 130MHz (typ) Bandwidth ♦ 2mAP-P Input Current—0dBm Overload Capability ♦ 76mW (typ) Power Dissipation ♦ 3.3V Single-Supply Operation ♦ Average Photocurrent Monitor Ordering Information TEMP RANGE PIN-PACKAGE MAX3657ETC PART -40°C to +85°C 12 Thin QFN MAX3657E/D -40°C to +85°C Die* MAX3657BE/D -40°C to +85°C Die* *Dice are designed to operate over a -40°C to +110°C junction temperature (TJ) range, but are tested and guaranteed at TA = +25°C. Pin Configuration appears at end of data sheet. SFP/SFF Transceivers BiDi Transceivers Typical Application Circuit 3.3V CVCC1 CVCC2 VCCZ VCC RFILT FILT CFILT OUT+ 1µF MAX3964 IN COUT OUT- RLOAD 200Ω LIMITING AMPLIFIER 1µF MAX3657 GND MON TO-46 HEADER RMON* *OPTIONAL COMPONENT ________________________________________________________________ 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 MAX3657 General Description MAX3657 155Mbps Low-Noise Transimpedance Amplifier ABSOLUTE MAXIMUM RATINGS Power-Supply Voltage ...........................................-0.5V to +6.0V Input Continuous Current ................................................±3.5mA Voltage at OUT+, OUT- ...................(VCC - 1.5V) to (VCC + 0.5V) Voltage at FILT, MON .................................-0.5V to (VCC + 0.5V) Continuous Power Dissipation 12-Pin QFN (derate 14.7mW/°C above +70°C) .........1176mW Operating Temperature Range 12-Pin QFN ......................................................-40°C to +85°C Operating Junction Temperature Range Die .................................................................-40°C to +150°C Storage Temperature Range .............................-55°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C Die Attach Temperature...................................................+400°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. DC ELECTRICAL CHARACTERISTICS (VCC1 = +2.97V to +3.63V, 200Ω load between OUT+ and OUT-, TA = -40°C to +85°C. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL Supply Current ICC Input Bias Voltage VIN Transimpedance Linear Range Small-Signal Transimpedance Z21 Output Common-Mode Voltage Output Resistance (Per Side) Maximum Differential Output Voltage Filter Resistor CONDITIONS IIN ≤ 1mA 0.95 < linearity < 1.05, referred to gain at 1µAP-P input 2 Differential output, IIN < 200nAP-P 44 AC-coupled outputs ROUT Single-ended output resistance VOUT(max) IIN = 2mAP-P, VOUT = (VOUT+) - (VOUT-) RFILT Monitor Gain Stability (Note 3) GNOM ∆G TYP MAX UNITS 23 34 mA 1 1.3 V µAP-P 54 65 VCC 0.225 DC Input Overload Monitor Nominal Gain MIN V 82 100 118 Ω 170 250 450 mVP-P 640 800 960 Ω 1.2 A/A 1 1.5 VCC = +3.3V, +25°C (Note 2) 0.8 1 IIN = 100µA to 1mA -1.5 +1.5 mA Die -1.5 +2.2 QFN package -3.0 +2.7 IIN = 2µA Die only -4.0 +3.4 IIN = 1µA Die only IIN = 5µA kΩ dB ±2.0 AC ELECTRICAL CHARACTERISTICS (VCC = +2.97V to +3.63V, 200Ω load between OUT+ and OUT-, CIN = 0.5pF, CFILT = 400pF, CVCC2 = 680pF, TA = -40°C to +85°C. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER Small-Signal Bandwidth SYMBOL BW-3dB Low-Frequency Cutoff CONDITIONS Relative to gain at 1MHz Input-Referred Noise Current TYP MAX 5 25 110 -3dB, IIN = 1µA AC Overload Pulse-Width Distortion MIN MHz 2 PWD In 300nAP-P ≤ IIN ≤ 2mAP-P UNITS kHz mAP-P 22 f = 100MHz (Note 4) psP-P 15 nARMS f = 117MHz 14 RMS Noise Density f = 100MHz 1.3 pA/√Hz Monitor Bandwidth IIN = 1µA 5 kHz 2 _______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier (VCC = +2.97V to +3.63V, RLOAD = 200Ω, CIN = 1.0pF, CFILT = 1000pF, CVCC2 = 0.01µF, TA = -40°C to +85°C. Typical values are at VCC = +3.3V, TA = +25°C, unless otherwise noted.) (Note 1) PARAMETER SYMBOL Small-Signal Bandwidth BW-3dB CONDITIONS Low-Frequency Cutoff -3dB, IIN = 1µA AC Overload εr ≥ 10 Pulse-Width Distortion TYP In RMS Noise Density MAX UNITS 95 MHz 5 25 kHz 1.6 mA 1µAP-P ≤ IIN ≤ 2mAP-P PWD Input-Referred Noise Current MIN Relative to gain at 1MHz 22 f = 50MHz (Note 4) 5 f = 100MHz 13 f = 100MHz 1.3 psP-P nARMS pA/√Hz Note 1: Die parameters are production tested at room temperature only, but are guaranteed by design from TA = -40°C to +85°C. AC characteristics guaranteed by design and characterization. Note 2: GNOM = IMON (1mA) / 1mA. Note 3: Stability is relative to the nominal gain at VCC = +3.3V, TA = +25°C. ∆G(IIN) dB = 10 log10 [ IMON(IIN) ] / [ IMON(1mA) - GNOM x (1mA - IIN)], VMON ≤ 2.1V, Input tr, tf > 550ps (20% to 80%). Note 4: Total noise integrated from 0 to f. Typical Operating Characteristics (MAX3657 E/D. VCC = 3.3V, CIN = 0.5pF, TA = +25°C, unless otherwise noted.) 1.0µAP-P 45 MAX3657 toc02 80 70 60 50 40 30 20 40 1.3 1.2 INPUT BIAS VOLTAGE (V) 50 90 SUPPLY CURRENT (mA) TRANSIMPEDANCE GAIN (kΩ) 0.2µAP-P 55 INPUT BIAS VOLTAGE vs. TEMPERATURE 100 MAX3657 toc01 60 SUPPLY CURRENT vs. TEMPERATURE MAX3657 toc03 SMALL-SIGNAL TRANSIMPEDANCE vs. TEMPERATURE 1.1 1.0 0.9 0.8 10 35 0 -40 -20 0 20 40 60 AMBIENT TEMPERATURE (°C) 80 0.7 -40 -20 0 20 40 60 AMBIENT TEMPERATURE (°C) 80 -40 -20 0 20 40 60 80 AMBIENT TEMPERATURE (°C) _______________________________________________________________________________________ 3 MAX3657 AC ELECTRICAL CHARACTERISTICS (12-PIN QFN) Typical Operating Characteristics (continued) (MAX3657 E/D. VCC = 3.3V, CIN = 0.5pF, TA = +25°C, unless otherwise noted.) PULSE-WIDTH DISTORTION vs. INPUT CURRENT AMPLITUDE DIFFERENTIAL OUTPUT VOLTAGE vs. INPUT CURRENT 70 60 50 40 -40°C +85°C +25°C 30 200 RLOAD = 200Ω Z21 = 54kΩ 100 0 RLOAD = 100Ω Z21 = 36kΩ -100 -200 20 95 92 DIFFERENTIAL OUTPUT 89 SINGLE-ENDED OUTPUT 86 83 -300 10 MAX3657 toc06 RLOAD = OPEN Z21 = 108kΩ OUTPUT MAGNITUDE (dBΩ) OUTPUT VOLTAGE (mVP-P) 80 300 FREQUENCY RESPONSE 98 MAX3657 toc05 90 VFILT = GND 80 -400 0 0.1 1 10 100 1000 -20 10,000 -15 -10 -5 0 5 10 15 20 100 1k 10k 100k 1M 10M 100M INPUT SIGNAL AMPLITUDE (µA) INPUT CURRENT (µA) FREQUENCY (Hz) BANDWIDTH vs. CAPACITANCE INPUT-REFERRED RMS NOISE vs. CAPACITANCE INPUT-REFERRED RMS NOISE vs. DC INPUT CURRENT 200 TJ = -40°C 175 TJ = +25°C 150 TJ = +110°C 125 100 75 50 30 25 20 TJ = +110°C TJ = +25°C TJ = -40°C 15 10 1.2 TJ = +110°C 1.0 1G MAX3657 toc09 225 35 INPUT-REFERRED NOISE (nARMS) 250 INPUT-REFERRED NOISE (nARMS) MAX3657 toc07 275 MAX3657 toc08 PULSE-WIDTH DISTORTION (ps) 400 MAX3657 toc04 100 BANDWIDTH (MHz) MAX3657 155Mbps Low-Noise Transimpedance Amplifier TJ = +25°C TJ = -40°C 0.8 0.6 0.4 0.2 25 0 0 0.1 0.3 0.5 0.7 0.9 1.1 1.3 0.6 0.8 MAX3657 toc10 1ns/div 1.4 0.1 1 10 100 10,000 OUTPUT EYE DIAGRAM (1mA ELECTRICAL INPUT) MAX3657 toc12 200mV -200mV 1ns/div 1000 DC CURRENT IN (µA) 40mV -200mV -50mV 1.2 MAX3657 toc11 200mV 40mV 10mV 1.0 OUTPUT EYE DIAGRAM (100µA ELECTRICAL INPUT) OUTPUT EYE DIAGRAM (1.0µA ELECTRICAL INPUT) 4 0.4 CAPACITANCE (pF) CAPACITANCE (pF) 50mV 0 0.2 1.5 1ns/div _______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier INPUT IMPEDANCE vs. FREQUENCY 6mV/ div 223-1 PRBS 223-1 PRBS 20mV/ div ZARLINK 1A358 PHOTODIODE + MAX3657 ZARLINK 1A358 PHOTODIODE + MAX3657 1ns/div 800 MAGNITUDE OF INPUT IMPEDANCE (Ω) MAX3657toc14 MAX3657toc13 OUTPUT EYE DIAGRAM (-1dBm OPTICAL INPUT) TJ = +25°C 750 MAX3657 toc15 OUTPUT EYE DIAGRAM (-30dBm OPTICAL INPUT) TJ = -40°C 700 650 600 TJ = +110°C 550 500 SMALL SIGNAL 450 400 350 300 1ns/div 100 1k 10k 100k 1M 10M 100M 1G FREQUENCY (Hz) Pin Description PIN NAME 1, 9, 11 N.C. No Connection. Do not connect. FUNCTION 2 GND Negative Supply Voltage. Both GND and GNDZ must be connected to ground. 3 GNDZ Negative Supply Voltage. Both GND and GNDZ must be connected to ground. 4 MON Photocurrent Monitor. This is a current output. Connect a resistor between MON and ground to monitor the average photocurrent. 5 IN 6 FILT Filter Connection (Optional). Use to bias the photodiode cathode. An internal 800Ω on-chip resistor is connected between this pin and VCCZ; an external decoupling capacitor connected to this pin forms a filter (see the Design Procedure section). 7 VCCZ Power-Supply Voltage. Both VCC and VCCZ must be connected to the supply. 8 VCC Power-Supply Voltage. Both VCC and VCCZ must be connected to the supply. 10 OUT+ Positive Data Output. This output has 100Ω back termination, increasing input current causes OUT+ to increase. 12 OUT- Negative Data Output. This output has 100Ω back termination, increasing input current causes OUT- to decrease. Signal Input. Connect to photodiode anode. _______________________________________________________________________________________ 5 MAX3657 Typical Operating Characteristics (continued) (MAX3657 E/D. VCC = 3.3V, CIN = 0.5pF, TA = +25°C, unless otherwise noted.) 155Mbps Low-Noise Transimpedance Amplifier MAX3657 Functional Diagram MAX3657 TRANSIMPEDANCE AMPLIFIER RF VOLTAGE AMPLIFIER IN OUTPUT BUFFER ROUT OUT+ OUTROUT +1.0V DC-CANCELLATION CIRCUIT LOWPASS FILTER MON VCCZ ROUT ENABLE FILT Detailed Description The MAX3657 transimpedance amplifier is designed for 155Mbps fiber-optic applications. The functional diagram of the MAX3657 comprises a transimpedance amplifier, a voltage amplifier, a DC-cancellation circuit, and a CML output buffer. Transimpedance Amplifier The signal current at the input flows into the summing node of a high-gain amplifier. Shunt feedback through resistor RF converts this current into a voltage. Schottky diodes clamp the output signal for large input currents (Figure 1). Voltage Amplifier The voltage amplifier provides additional gain and converts the transimpedance amplifier single-ended output signal into a differential signal. Output Buffer The output buffer provides a reverse-terminated voltage output and is designed to drive a 200Ω differential load between OUT+ and OUT-. For optimum supplynoise rejection, the MAX3657 should be terminated with a differential load. The MAX3657 single-ended outputs 6 do not drive a DC-coupled grounded load. The outputs should be AC-coupled or terminated to VCC. If a singleended output is required, both the used and the unused outputs should be terminated in a similar manner. DC-Cancellation Circuit The DC-cancellation circuit uses low-frequency feedback to remove the DC component of the input signal (Figure 2). This feature centers the input signal within the transimpedance amplifier’s linear range, thereby reducing pulse-width distortion. The DC-cancellation circuit is internally compensated and does not require external capacitors. This circuit minimizes pulse-width distortion for data sequences that exhibit a 50% mark density. A mark density significantly different from 50% causes the MAX3657 to generate pulse-width distortion. Grounding the FILT pin disables the DC-cancellation circuit. For normal operation, the DC-cancellation circuit must be enabled. The DC-cancellation current is drawn from the input and creates noise. For low-level signals with little or no DC component, the added noise is insignificant. However, amplifier noise increases for signals with significant DC component (see the Typical Operating Characteristics). _______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier AMPLITUDE MAX3657 AMPLITUDE INPUT FROM PHOTODIODE TIME TIME OUTPUT (SMALL SIGNALS) INPUT AFTER DC CANCELLATION OUTPUT (LARGE SIGNALS) Figure 2. Effects of DC Cancellation on Input Figure 1. MAX3657 Limited Outputs Photocurrent Monitor Select RMON The MAX3657 includes an average photocurrent monitor. The current at MON is approximately equal to the DC current at IN. Best monitor accuracy is obtained when data input edge time is longer than 500ps. Connect a resistor between MON and ground to monitor the average photocurrent. Select RMON as large as possible: Design Procedure Select Photodiode Noise performance and bandwidth are adversely affected by stray capacitance on the TIA input node. Select a low-capacitance photodiode to minimize the total input capacitance on this pin. The MAX3657 is optimized for 0.5pF of capacitance on the input. Assembling the MAX3657 in die form using chip and wire technology provides the lowest capacitance input and the best possible performance. Select CFILT Supply voltage noise at the cathode of the photodiode produces a current I = CPD ∆V/∆t, which reduces the receiver sensitivity (C PD is the photodiode capacitance). The filter resistor of the MAX3657, combined with an external capacitor, can be used to reduce the noise (see the Typical Application Circuit). Current generated by supply-noise voltage is divided between CFILT and CPD. To obtain a good optical sensitivity, select CFILT > 400pF. Select Supply Filter The MAX3657 requires wideband power-supply decoupling. Power-supply bypassing should provide low impedance between VCC and ground for frequencies between 10kHz and 200MHz. Use LC filtering at the main supply terminal and decoupling capacitors as close to the die as possible. RMON = 2.1V IMONMAX where IMONMAX is the largest average input current observed. Select Coupling Capacitors A receiver built with the MAX3657 has a bandpass frequency response. The low-frequency cutoff due to the coupling capacitors and load resistors is: LFCTERM = 1 2π x RLOAD x CCOUPLE Select CCOUPLE so the low-frequency cutoff due to the load resistors and coupling capacitors is much lower than the low-frequency cutoff of the MAX3657. The coupling capacitor should be 0.1µF or larger, but 1.0µF is recommended for lowest jitter. Refer to Maxim Application Note HFAN-1.1: Choosing AC-Coupling Capacitors for more information. Layout Considerations Figure 3 shows a suggested layout for a TO header for the MAX3657. Wire Bonding For high-current density and reliable operation, the MAX3657 uses gold metalization. For best results, use gold-wire ball-bonding techniques. Use caution if attempting wedge bonding. Die size is 41 mils x 48 mils, (1040µm x 1220µm) and die thickness is 15 mils (380µm). The bond pad is 94.4µm x 94.4µm and its metal thickness is 1.2µm. Refer to Maxim Application Note HFAN- 8.0.1: _______________________________________________________________________________________ 7 MAX3657 155Mbps Low-Noise Transimpedance Amplifier CASE CFILT CVCC 4-PIN TO HEADER FILT IN VCC Z VCC MO N GN DZ GN D OU T+ OU T- PHOTODIODE MAX3657 E/D MOUNTED ON CFILT OUTPUT POLARITIES REVERSED FOR MAX3657BE/E CASE IS GROUND CASE CFILT CVCC 5-PIN TO HEADER FILT IN MON VCCZ VCC GNDZ GND OUT+ OUT- PHOTODIODE MAX3657 E/D MOUNTED ON CFILT OUTPUT POLARITIES REVERSED FOR MAX3657BE/E CASE IS GROUND Figure 3. Suggested TO Header Layout 8 _______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier Table 1. Optical Power Relations* PARAMETER SYMBOL RELATION Applications Information Average power PAVG Optical Power Relations Extinction ratio re re = P1/P0 Optical power of a 1 P1 re r e P1 P 1 ==2P2AVG PAVG re + 1 re + 1 Optical power of a 0 P0 P0 = 2PAVG/(re + 1) PIN PIN = P1 − P0 = re 2PAVG re + 1 Many of the MAX3657 specifications relate to the inputsignal amplitude. When working with optical receivers, the input is sometimes expressed in terms of average optical power and extinction ratio. Figure 4 and Table 1 show relations that are helpful for converting optical power to input signal when designing with the MAX3657. 12.7 x in x (re + 1) Sensitivity = 10log x 1000 dBm 2 x ρ x (re − 1) Optical modulation amplitude PAVG = (P0 + P1)/2 r −1 PIN = P1 − P0 = 2PAVG e re + 1 Optical Sensitivity Calculation The input-referred RMS noise current (i n ) of the MAX3657 generally determines the receiver sensitivity. To obtain a system bit-error rate (BER) of 1E-10, the signal-to-noise ratio must always exceed 12.7. The input sensitivity, expressed in average power, can be estimated as: MAX3657 Understanding Bonding Coordinates and Physical Die Size for more information on bond-pad coordinates. *Assuming a 50% average mark density. Actual results may vary depending on supply noise, output filter, limiting amplifier sensitivity, and other factors (refer to Maxim Application Note HFAN-3.0.0: Accurately Estimating Optical Receiver Sensitivity). Input Optical Overload where ρ is the photodiode responsivity in A/W and in is the RMS noise current in amps. For example, with photodiode responsivity of 0.9A/W, an extinction ratio of 10 and 15nA input-referred noise, the sensitivity of the MAX3657 is: 12.7 x 15nA x 11 Sensitivity = 10log x 1000 dBm = − 38dBm 2 x 0.9A / W x 9 Overload is the largest input the MAX3657 accepts while meeting the pulse-width distortion specification. Optical overload can be estimated in terms of average power with the following equation: 2mA Overload = 10log x 1000 dBm x 2 ρ For example, if photodiode responsivity is 1.0A/W, the input overload is 0dBm. Optical Linear Range The MAX3657 has high gain, which limits the output for large input signals. The MAX3657 operates in a linear range for inputs not exceeding: OPTICAL POWER P1 2µA (re + 1) Linear Range = 10log x 1000 dBm 2 x ρ (re − 1) PAVG For example, with photodiode responsivity of 0.9A/W and an extinction ratio of 10 the linear range is: P0 TIME 2µA x 11 Linear Range = 10log x 1000 dBm = − 28dBm 2 x 0.9 x 9 Figure 4. Optical Power Relations _______________________________________________________________________________________ 9 MAX3657 155Mbps Low-Noise Transimpedance Amplifier Interface Schematics Equivalent Output Interface The MAX3657 has a differential CML output structure with 100Ω back termination (200Ω differentially). Figure 5 is a simplified diagram of the output interface. The output current is divided between the internal 100Ω resistor and the external load resistance. Because of the CML structure, the maximum output-signal amplitude is affected by load impedance. Note that the internal back termination is 100Ω single ended and external termination is recommended to interface the device to 50Ω test equipment. For example, if single-ended operation in a 50Ω system is required, first match the output Pad Coordinates Table 2 lists center-pad coordinates for the MAX3657 bond pads. Refer to Maxim Application Note HFAN8.0.1: Understanding Bonding Coordinates and Physical Die Size for more information on bond-pad coordinates. Table 2. Bond-Pad Information VCC NAME VCC ROUT 100Ω of the MAX3657 to the 50Ω controlled impedance by placing a 100Ω pullup resistor in parallel with the output. Then establish similar loading conditions on the unused output. Note that the loading conditions affect the overall gain of the MAX3657. Figures 6a, 6b, and 6c show alternate interface schemes for the MAX3657. PAD ROUT 100Ω OUT+ VCC OUT- 4.5mA COORDINATES (µm) MAX3657 MAX3657B X BP1 OUT- OUT+ 47.2 994.8 BP2 GND GND 52.2 484.6 BP3 GNDZ GNDZ 52.2 357.7 BP4 MON MON 395.5 47.2 BP5 IN IN 522.3 47.2 BP6 FILT FILT 648.5 47.2 BP7 N.C. N.C. 808.5 49.9 BP8 VCCZ VCCZ 808.5 176.8 BP9 VCC VCC 808.5 303.7 BP10 OUT+ OUT- 808.5 994.8 BP11 N.C. N.C. 741.1 859.9 Figure 5. Equivalent Output Interface 10 Y ______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier MAX3657 VCC 100Ω 100Ω 100Ω∗ 100Ω∗ 50Ω 50Ω 50Ω∗ 50Ω∗ L DIFFERENTIAL CML INPUT STAGE MAX3657 CML OUTPUT STAGE *COMPONENT NOT REQUIRED IF L < 10cm. Figure 6a. 50Ω DC-Coupled Interface VCC 100Ω∗ 100Ω 50Ω 100Ω∗ 100Ω 50Ω 50Ω∗ L SINGLE-ENDED INPUT STAGE MAX3657 CML OUTPUT STAGE NOTE: THE PARALLEL COMBINATION AT THE UNUSED OUTPUT CAN BE REPLACED BY A SINGLE EQUIVALENT 33Ω RESISTOR. *COMPONENT NOT REQUIRED IF L < 10cm. Figure 6b. 50Ω DC-Coupled Single-Ended Output Interface ______________________________________________________________________________________ 11 MAX3657 155Mbps Low-Noise Transimpedance Amplifier VCC 100Ω∗ 100Ω 100Ω∗ 100Ω 50Ω 50Ω∗ L 50Ω 50Ω LOAD TO GROUND MAX3657 CML OUTPUT STAGE *COMPONENT NOT REQUIRED IF L < 10cm Figure 6c. 50Ω AC-Coupled Single-Ended Output Interface VCC VCC 800Ω FILT Figure 7. FILT Interface 12 MON Figure 8. MON Interface ______________________________________________________________________________________ 155Mbps Low-Noise Transimpedance Amplifier Topography for MAX3657 TOP VIEW OUT- 1 10 11 GND 2 GNDZ 3 OUT+ N.C. 0.048in 1.219mm 9 VCC 8 VCCZ N.C. 1 GND 2 GNDZ 3 OUT- N.C. OUT+ 12 11 10 MAX3657 4 5 6 MON IN FILT 9 N.C. 8 VCC 7 VCCZ QFN *EXPOSED PAD IS CONNECTED TO GND. 4 5 6 7 MON IN FILT N.C. 0.041in 1.041mm Chip Information Topography for MAX3657B OUT+ 1 10 11 GND 2 GNDZ 3 OUT- TRANSISTOR COUNT: 417 PROCESS: Silicon bipolar SUBSTRATE: Connected to GND DIE SIZE: 1.04mm x 1.22mm N.C. 0.048in 1.219mm 9 VCC 8 VCCZ 4 5 6 7 MON IN FILT N.C. 0.041in 1.041mm ______________________________________________________________________________________ 13 MAX3657 Pin Configuration Chip Topographies 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. 12x16L QFN THIN.EPS MAX3657 155Mbps Low-Noise Transimpedance Amplifier D2 0.10 M C A B b D D2/2 D/2 E/2 E2/2 CL (NE - 1) X e E E2 L e CL k (ND - 1) X e CL 0.10 C CL 0.08 C A A2 A1 L L e e PACKAGE OUTLINE 12, 16L, THIN QFN, 3x3x0.8mm 21-0136 14 ______________________________________________________________________________________ E 1 2 155Mbps Low-Noise Transimpedance Amplifier EXPOSED PAD VARIATIONS DOWN BONDS ALLOWED NOTES: 1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994. 2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES. 3. N IS THE TOTAL NUMBER OF TERMINALS. 4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE. 5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN 0.20 mm AND 0.25 mm FROM TERMINAL TIP. 6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY. 7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION. 8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS. 9. DRAWING CONFORMS TO JEDEC MO220 REVISION C. PACKAGE OUTLINE 12, 16L, THIN QFN, 3x3x0.8mm 21-0136 E 2 2 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15 © 2004 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products. MAX3657 Package Information (continued) (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.