MAX40660ATB/VY+

Click here to ask about the production status of specific part numbers. MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR General Description Benefits and Features The MAX40660/MAX40661 are transimpedance amplifiers for optical distance measurement receivers in LiDAR applications. Low noise, high gain, low group delay, and fast recovery from overload make these TIAs ideal for distance-measurement applications. Important features include 2.1pA input-referred noise density (MAX40660), an internal input clamp, pin-selectable 25kΩ and 50kΩ transimpedance, and wide bandwidth (490MHz (typ) for the MAX40660 with 0.5pF input capacitance and 25kΩ transimpedance; 160MHz (typ) for the MAX40661 with 10pF input capacitance). An offset current input allows optional adjustment of input offset current. A low-power/standby control input reduces the supply current by better than 80% to help reduce average power supply current between pulses. The MAX40660/MAX40661 transimpedance amplifiers feature AEC-Q100 qualification over the -40°C to +125°C automotive operating temperature range and are available in a 3mm x 3mm, 10-lead TDFN package with side-wettable flanks, making them excellent choices for automotive LiDAR applications. ● AEC-Q100 ● Enables ASIL Compliance (FMEDA Available upon Request) ● MAX40660 • Optimized for CIN = 0.25pF to 5pF • Bandwidth = 490MHz (typ) In addition to the TDFN package, the MAX40660 is available as bare die. Applications ● ● ● ● ● Optical Distance Measurement LiDAR Receivers Industrial Safety Systems Autonomous Driving Systems Automotive Applications 19-100541; Rev 4; 1/21 ● MAX40661 • Optimized for CIN = 5pF to 12pF • Bandwidth (CIN = 10pF) = 160MHz (typ), 100MHz (min) ● Low Noise ● Two Pin-Selectable Transimpedance Values • 25kΩ • 50kΩ ● ● ● ● ● ● Internal Clamp for Input Current up to 2A (Transient) Fast Overload Recovery: 2ns at 100mA Offset Input Provides Offset Adjust Feature LP Input Reduces Power Dissipation Between Pulses 3.3V Operation 10-Pin TDFN (Side-Wettable) or Bare Die Ordering Information appears at end of data sheet. MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Simplified Block Diagram VCL VCC CURRENT CLAMP VCC BIAS BLOCK MAX40660 MAX40661 50Ω OUTP IN VBIAS OUTN 50Ω OFFSE T LP GND www.maximintegrated.com VCC LOW-POWER MODE SELE CT GND GAIN Maxim Integrated | 2 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR TABLE OF CONTENTS General Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Benefits and Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Simplified Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Absolute Maximum Ratings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 10 TDFN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Typical Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Pin Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Die Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Detailed Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Gain Stage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Gain Stage 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 OFFSET Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 LP Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Photodiode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Supply Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Layout Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Slew Rate on the Supply Ramp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Typical Application Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 www.maximintegrated.com Maxim Integrated | 3 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Absolute Maximum Ratings Supply Voltage ...................................................... -0.3V to +3.6V Current Into IN (10ns pulse width, 0.5% duty cycle) ...............-2A Current Into IN, OFFSET (continuous) ................. -0.4mA to 0mA Current into LP, Gain (continuous) .................... -10mA to +10mA Current into OUTP and OUTN (continuous)...... -20mA to +20mA Voltage at OUTN, OUTP ............................................ VCC + 0.3V Voltage at GAIN, LP ..................................... -0.3V to VCC + 0.3V Operating Temperature Range ...........................-40°C to +125°C Operating Junction Temperature Range (die) ....-40°C to +150°C Storage Temperature Range ..............................-55°C to +150°C Soldering Temperature (reflow) ........................................ +260°C Die Attach Temperature.................................................... +400°C Continuous Power Dissipation (TA = +125°C, derate 24.4mW/°C above +70°C (multilayer board))................................1951.20mW 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. Package Information 10 TDFN Package Code T1033Y+4C Outline Number 21-100317 Land Pattern Number 90-0003 Thermal Resistance, Single-Layer Board Junction to Ambient (θJA) 54°C/W Junction to Case (θJC) 9°C/W Thermal Resistance, Four-Layer Board Junction to Ambient (θJA) 41°C/W Junction to Case (θJC) 9°C/W For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (VCC = +2.9V to +3.5V, VCL = VCC, 100Ω AC-coupled load between OUTN and OUTP, TA = -40°C to +125°C, CIN (MAX40660) = 0.5pF (Note 1), CIN (MAX40661) = 8pF (Note 1), Input current is defined as flowing out of IN. Typical values are at VCC = +3.3V and TA = +25°C, unless otherwise noted.) PARAMETER Power Supply Current SYMBOL ICC VCL Quiescent Supply Current Input Bias Voltage Transimpedance Linearity www.maximintegrated.com VBIAS TYP MAX LP > 2.0V (logic-high) (Note 4) CONDITIONS MIN 41 70 LP < 0.8V (logic-low) (Note 4) 8 13 LP > 2.0V (logic-high) (Note 4) 0.1 20 LP < 0.8V (logic-low) (Note 4) 0.1 20 IN and OFFSET 0.85 1.0 GAIN = GND (Note 2) -10 ±2 +10 GAIN = VCC (Note 2) -10 ±2 +10 UNITS mA µA V % Maxim Integrated | 4 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Electrical Characteristics (continued) (VCC = +2.9V to +3.5V, VCL = VCC, 100Ω AC-coupled load between OUTN and OUTP, TA = -40°C to +125°C, CIN (MAX40660) = 0.5pF (Note 1), CIN (MAX40661) = 8pF (Note 1), Input current is defined as flowing out of IN. Typical values are at VCC = +3.3V and TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL Z21 Transimpedance CONDITIONS MIN TYP MAX GAIN logic-low, IIN < 2µAP-P 18 25 32 GAIN logic-high, IIN < 1µAP-P 36 50 64 In low-power standby mode: LP < VIL, IIN = 1µARMS, fIN = 100MHz. OFFSET Input Transimpedance Overload Recovery Time 300 kΩ mΩ GAIN logic-low, IOFFSET < 2µAP-P 18 25 32 GAIN logic-high, IOFFSET < 1µAP-P 36 50 64 0 to -100mA input current UNITS 2 kΩ ns Input Logic 0 VIL GAIN, LP (Note 4) 0 Input Logic 1 VIH GAIN, LP (Note 4) 2.0 Logic Input Current Low IIL GAIN, LP (Note 4) ±0.001 ±1.0 µA Logic Input Current High IIH GAIN, LP (Note 4) ±0.001 ±1 µA Time from LP > VIL to output commonmode voltage 90% of nominal value. Measured at OUTP and OUTN. Standby De-Assert Delay Output Common-Mode Voltage ΔVOUT Output Impedance ZOUT Maximum Differential Output Voltage Swing Input Resistance Bandwidth Input Noise Density VOUT(MAX) VCC 0.73 IIN = 0mA, GAIN = GND -200 IIN = 0mA, GAIN = VCC -400 ns VCC 0.40 V mV Single-ended 40 50 60 IIN = 0mA to -200µA pulse, GAIN logiclow 475 825 1290 IIN = 0mA to -200µA pulse, GAIN logichigh 500 920 1490 MAX40660, CIN = 0.5pF 300 490 660 MAX40660, CIN = 10pF 70 165 280 MAX40661, CIN = 10pF (Note 3) 100 160 210 MAX40661, CIN = 5pF (Note 3) 130 200 280 Ω mV RIN BW V VCC 200 VCC 1.15 Differential Output Offset +0.8 65 MAX40660, f = 10MHz, CIN = 0.8pF 2.1 MAX40660, f = 10MHz, CIN = 10pF 2.8 MAX40661, f = 10MHz, CIN = 5pF 2.5 MAX40661, f = 10MHz, CIN = 8pF 2.7 MAX40661, f = 10MHz, CIN = 10pF 3.0 Ω MHz pA/√Hz pA/√Hz Note 1: Limits are 100% tested at TA = +25°C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization. For die-form sale, EC table parameters are not tested, excepting parameters with Note 4. Specs are guaranteed by design. www.maximintegrated.com Maxim Integrated | 5 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Note 2: Linearity is calculated as follows: For 25kΩ transimpedance, Linearity = (Large signal gain at 20µA – Large signal gain at 2µA)/Large signal gain at 2µA, where large signal gain at X is (VOUT at I_IN = X - VOUT at I_IN = 0)/I_IN For 50kΩ transimpedance, Linearity = (Large signal gain at 10µA – Large signal gain at 1µA)/Large signal gain at 1µA, where large signal gain at X is (VOUT at I_IN = X - VOUT at I_IN = 0)/I_IN Note 3: -3dB bandwidth is measured relative to the gain at 10MHz. Note 4: For die only. Limits are 100% tested at TA = +25°C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization. www.maximintegrated.com Maxim Integrated | 6 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Operating Characteristics (VCC = +3.3V, CIN = 0.5pF (MAX40660), CIN = 8pF (MAX40661), TA= +25°C; unless otherwise noted.) L OW-POWER STA ND B Y S UPPL Y CURRE NT v s . TEMP ERA TURE LOW-POWER STANDB Y SUPPLY CURRENT v s . SUPPLY VOLTA GE OUTPUT COMMON-MODE VOLTAGE CHANGE (%) TA = -40°C TA = +25°C OUTPUT COMMON-MODE VOLTAGE (V) TA = +125°C OUTPUT COMMON-MODE VOL TA GE v s . TEMPERATURE OUTPUT COMMON-MODE VOL TA GE v s . TEMPERATURE NORMALIZED AT VCC = 3.3V OUTPUT OFFSET VOLTAGE v s . TEMPERATURE OUTPUT OFFSET VOLTAGE (V) IIN = 0μA VCC = 3.3V www.maximintegrated.com Maxim Integrated | 7 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Operating Characteristics (continued) (VCC = +3.3V, CIN = 0.5pF (MAX40660), CIN = 8pF (MAX40661), TA= +25°C; unless otherwise noted.) OUTPUT DIFFERENTIAL VOLTAGE (mV) OUTPUT DIFFERENTIAL VOLTA GE v s . I NPUT DC CURRENT www.maximintegrated.com IOFFSET = +20μA Maxim Integrated | 8 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Operating Characteristics (continued) (VCC = +3.3V, CIN = 0.5pF (MAX40660), CIN = 8pF (MAX40661), TA= +25°C; unless otherwise noted.) GAIN = 25kΩ CIN = 0.5pF GAIN = 50kΩ CIN = 0.5pF GAIN = 25kΩ CIN = 10pF GAIN = 50kΩ CIN = 10pF www.maximintegrated.com Maxim Integrated | 9 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Operating Characteristics (continued) (VCC = +3.3V, CIN = 0.5pF (MAX40660), CIN = 8pF (MAX40661), TA= +25°C; unless otherwise noted.) www.maximintegrated.com Maxim Integrated | 10 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Operating Characteristics (continued) (VCC = +3.3V, CIN = 0.5pF (MAX40660), CIN = 8pF (MAX40661), TA= +25°C; unless otherwise noted.) MA X40660 PULSE RESPONSE OUTPUT DIFFERENTIAL (V) OUTPUT DIFFERENTIAL (V) MA X40660 PULSE RESPONSE TIME (ns) MA X40661 PULSE RESPONSE OUTPUT DIFFERENTIAL (V) TIME (ns) TRANSIMPEDANCE AT LP MODE (mΩ) TIME (ns) www.maximintegrated.com TRANSIMPEDANCE AT LP MODE (mΩ) OUTPUT DIFFERENTIAL (V) MA X40661 PULSE RESPONSE TIME (ns) Maxim Integrated | 11 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Pin Configuration TOP VIEW GND 10 VCC OUTP OUTN GND 9 8 7 6 MAX40660 MAX MAX40661 40661 EP* + 1 2 3 VCL LP IN OFFSET GAIN 4 5 TDFN-EP 3mm x 3mm * THE EXPOSED PAD MUST BE CONNECTED TO CIRCUIT BOARD GROUND FOR PROPER THERMAL AND ELECTRICAL PERFORMANCE. Pin Description PIN NAME 1 VCL Power Supply Connection for Input Current Clamp. Connect to VCC. FUNCTION 2 LP Enable/Low-Power Input. Logic-high = normal operation. Logic-low = low-power standby. 3 IN Signal Input. Connect to photodiode cathode through a coupling capacitor when using positive bias voltage at cathode. Connect to photodiode cathode when using negative bias voltage at anode. 4 OFFSET Offset Adjustment Input. Sink current from this input to adjust the effective input offset current. If offset adjustment is not needed, this pin should be left unconnected. 5 GAIN Gain Select Input. Connect to GND for gain = 25kΩ. Connect to VCC for gain = 50kΩ. 6, 10 GND Circuit Ground 7 OUTN Negative 50Ω Output. Increasing input current causes OUT- to decrease. 8 OUTP Positive 50Ω Output. Increasing input current causes OUT+ to increase. 9 VCC EP EP www.maximintegrated.com +3.3V Supply Voltage Exposed Pad (GND). This pad must be connected to ground. Maxim Integrated | 12 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Die Information BOND PAD NAME X COORDINATE (μm) Y COORDINATE (μm) CENTER 0 0 VCLAMP -548 638 PRB For VCLAMP -548 535 LPM -548 411 www.maximintegrated.com Maxim Integrated | 13 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Die Information (continued) BOND PAD NAME X COORDINATE (μm) Y COORDINATE (μm) PRB For LPM -548 286 IN -548 21 PRB for IN -548 181 OFFSET -548 -130 PRB For OFFSET -548 -290 GSEL -548 -517 PRB For GSEL -548 -393 VEE_PAD6 548 -518 PRB For GND 548 -415 OUTN 548 -130 PRB For OUTN 548 -311 OUTP 548 20 PRB For OUTP 548 202 VCC_PAD2 535 305 VCC_PAD1 535 408 PRB For VCC 535 511 VEE_PAD10 476 638 PRB For GND 373 638 VEE_DBTOP4 270 638 VEE_DBTOP3 166 638 VEE_DBTOP2 63 638 VEE_DBTOP1 -39 638 VEE_DBBOT1 -523 -638 VEE_DBBOT2 -420 -638 VEE_DBBOT3 -317 -638 VEE_DBBOT4 -214 -638 The back side of the die must be connected to GND. www.maximintegrated.com Maxim Integrated | 14 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Detailed Description The MAX40660/MAX40661 transimpedance amplifiers are designed for optical distance measurement applications and are comprised of a transimpedance amplifier input stage and a voltage amplifier/output buffer. The input stage accepts negative input current pulses; the input current will flow out of the TIA's input pin. Gain Stage 1 When a photodiode with negative bias voltage is connected to the TIA input, the signal current flows out of the amplifier's summing node and into the photodiode. The input current flows through an internal load resistor to develop a voltage that is then applied to the input of the second stage. An internal clamp circuit protects against input currents as high as 2A for a 10ns pulse at 0.5% duty cycle. (Longer pulses or higher duty cycles will reduce this value.) The clamp circuit also maintains very fast overload recovery times (about 2ns) for input currents up to 100mA (see Typical Operating Characteristics). Gain Stage 2 The second gain stage provides additional gain and converts the transimpedance amplifier's single-ended output into a differential signal. This stage is designed to drive a 100Ω differential load between OUT+ and OUT-. For optimum supply noise rejection, the outputs should be terminated with a differential load. The outputs are not intended to drive a DC-coupled grounded load. The outputs should be AC-coupled or terminated to VCC. If a single-ended output is required, both the used and unused outputs should be terminated in a similar manner. OFFSET Input OFFSET is a current input. The offset input current, IOFFSET, is the current flowing from the OFFSET pin. This current affects the TIA's output voltage with a polarity opposite that of the current flowing from IN, so it may be used to effectively apply an offset correction to the output voltage. The OFFSET pin is biased to the same voltage as the IN pin. TOC 9A, 9B, 10A, and 10B show different load line transfer functions at the output with varying IIN and IOFFSET input currents (see Typical Operating Characteristics). IOFFSET inputs shown in these TOCs may be used for applications where the linear region of the output is desired for a range of input current from the sensor. Use of OFFSET is optional. If the OFFSET function is not required, simply leave this input unconnected. LP Input The LP (Low Power) Input accepts a logic signal that can be used to put the TIA into a low-power standby mode, thereby reducing the supply current significantly. Driving this input with a logic-high enables the TIA, while a logic-low disables the circuit and places it into a low-power mode. The MAX40660/MAX40661 transimpedance amplifiers return to active mode from low-power mode in 200ns (typ). www.maximintegrated.com Maxim Integrated | 15 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Applications Information Photodiode Noise performance and bandwidth are adversely affected by capacitance on a TIA's input node. Although the MAX40660/ MAX40661 are less sensitive than most TIAs to input capacitance, it is good practice to minimize any unnecessary capacitance. The MAX40660 is optimized for 0.25pF to 5pF of capacitance on the input. Selecting a low-capacitance photodiode for use with the MAX40660 helps to minimize the total input capacitance on the input pin. Assembling the TIA in die form using chip and wire technology provides the lowest capacitance input and the best possible performance. The MAX40661 is optimized for use with higher-capacitance photodiodes in the range of 5pF to 12pF. Supply Filter Sensitive optical receivers require wide-band power supply decoupling. Power supply bypassing should provide low impedance between VCC and ground for frequencies between 10kHz and 700MHz. Isolate the amplifier from noise sources with LC supply filters and shielding. Place a supply filter as close to the amplifier as possible. Layout Considerations Some critical layout guidelines are listed below. ● A differential microstrip is the recommended layout for MAX40660/MAX40661 outputs with terminations done close to the outputs. Care must be taken to avoid unwanted stubs by removing ground below the traces that are not part of the 50Ω termination line leading into input pins. The parasitic capacitance created between traces and ground slow down and even distort the signals by creating reflections on the path. ● The input trace connecting the photodiode to IN of the MAX40660/MAX40661 should be as short as possible and have ground etched/removed underneath. This will reduce/avoid unwanted parasitic capacitance created in the PCB. Having longer trace lengths will increase the parasitic inductance in signal trace paths. ● Use a PC board with a low-impedance ground plane. ● Mount one or more 10nF ceramic capacitors between GND and VCC as close to the pins as possible. Multiple bypass capacitors help to reduce the effect of trace impedance and capacitor ESR. ● Choose bypass capacitors for minimum inductance and ESR. ● Use a 100Ω termination resistor for the output, connected directly between OUTP and OUTN after the AC-coupling capacitors, if practical. If the destination inputs can't be located adjacent to the outputs, use a 100Ω microstrip between the output pins and the termination resistor, which should be close to the inputs of the destination component. This will avoid the creation of stub beyond the termination resistor, which will cause reflections. The added length of the differential trace has less degrading affects than added stub length. ● Minimize any parasitic layout inductance. ● It is recommended to use higher-performance substrate materials (e.g., Rogers). Slew Rate on the Supply Ramp Ramp rate of the supply needs to be 50μs or more to make sure the core clamp is not triggered during the power-up. If the supply ramp is faster than 50μs, then the core clamp triggers and there will be excess current consumption for about 6μs. www.maximintegrated.com Maxim Integrated | 16 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Application Circuits 3.3V 3.3V CBYPASS CCL-BYPASS VCL VCC CURRENT CLAMP VCC BIAS BLOCK MAX40660 MAX40661 50Ω IN OUTP 0.1µF 100Ω VBIAS OUTN RLIMIT CAPD-BYPASS LP -VAPD 3.3V 0.1µF 50Ω OFFSE T VCC LOW-POWER MODE SELE CT GND GND GAIN DC-COUP LE D A P D RE CEIVE R TIA The APD's cathode is connected to to the TIA's input, and the anode is connected to the negative bias voltage through a resistor. Incident light pulses cause current to flow from the IN pin and into the APD. This input current also flows through an internal resistor to create a voltage, which is then amplified by the second stage to create a differential output signal that can drive a high-speed ADC or comparator. www.maximintegrated.com Maxim Integrated | 17 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Typical Application Circuits (continued) 3.3V 3.3V CCL-BYPASS VCL +V APD CBYPASS VCC CURRENT CLAMP 0.1µF 3.3V VCC BIAS BLOCK MA X 40 66 0 MA X 40 66 1 RLIMIT IN OUTP 100Ω VBIAS LVDS OUTPUT VCC 50Ω MAX 40025/ MAX 40026 OUT+ 100Ω FPGA OUTN 50Ω OFFSE T GND VCC LP 3.3V LOW-POWER MODE SELE CT GND GND GAIN A C-COUP LE D A P D RE CEIVE R TIA The APD's cathode is connected through a coupling capacitor to to the TIA's input, with the anode connected to ground. The bias voltage in this case is positive, and is connected to the cathode through a resistor. Incident light pulses cause current to flow from the IN pin and into the APD. This input current also flows through an internal resistor to create a voltage, which is then amplified by the second stage to create a differential output signal that can drive a high-speed ADC or comparator. Ordering Information TEMP RANGE PIN-PACKAGE TOP MARK CIN (pF) BANDWIDTH (MHz) -40°C to +125°C 10 TDFN — 0.25 to 5 490 MAX40660ATB/VY+ -40°C to +125°C 10 TDFN (side-wettable) +BCYBAC 0.25 to 5 490 MAX40660A/D+* -40°C to +125°C Dice* — 0.25 to 5 490 MAX40661ATB+** -40°C to +125°C 10 TDFN — 5 to 12 160 MAX40661ATB/VY+ -40°C to +125°C 10 TDFN (side-wettable) +BCXNAA 5 to 12 160 MAX40661A/D+** -40°C to +125°C Dice* — 5 to 12 160 PART NUMBER MAX40660ATB+** *Dice are designed to operate over a -40°C to +125°C junction temperature (Tj) range, but are tested and guaranteed at TA = +25°C. + Denotes a lead(Pb)-free/RoHS-compliant package. T = Tape and reel. /V denotes an automotive qualified part. **Future product—contact factory for availability. www.maximintegrated.com Maxim Integrated | 18 MAX40660/MAX40661 High-Bandwidth Automotive Transimpedance Amplifier with Fast Output Recovery and Input Current Clamp for LiDAR Revision History REVISION NUMBER REVISION DATE PAGES CHANGED 0 4/19 Initial release — 1 6/19 Updated Ordering Information 14 2 7/19 Updated General Description, Benefits and Features, Electrical Characteristics, and Ordering Information 3 6/20 Updated Electrical Characteristics, Typical Operating Characteristics, Die Information, Typical Application Circuits, and Ordering Information 4 1/21 Updated Electrical Characteristics, Typical Operating Characteristics DESCRIPTION 1, 4, 14 4, 5, 6, 8, 9, 10, 11, 13, 14, 19 5, 9, 10 For pricing, delivery, and ordering information, please visit Maxim Integrated’s online storefront at https://www.maximintegrated.com/en/storefront/storefront.html. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. © 2021 Maxim Integrated Products, Inc.