LTC6561 Four-Channel Multiplexed Transimpedance Amplifier ...

1 LTC65611 Rev. CFor more information APPLICATION FEATURESDESCRIPTIONFour-Channel Multiplexed Transimpedance Amplifier with Output MultiplexingThe LTC 6561 is a low-noise Four-Channel , transimped-ance Amplifier (TIA)with 220 MHz bandwidth. The LTC6561 multi-channel Transimpedance Amplifier s low noise, high Transimpedance , and low power dissipation are ideal for LIDAR receivers using Avalanche Photodiodes (APDs). The Amplifier features 74k Transimpedance gain and 30 A linear input current range. Using an APD input cir-cuit with a total capacitance of 2pF, the input current noise density is Hz at 200 MHz.

2 With lower capacitance, noise and bandwidth improve further. Only a 5V single supply is needed and the device consumes only 200mW. Utilizing the internal 4-to-1 MUX along with the LTC6561 s output MUX; multiple 4-channel LTC6561 devices can be combined to directly interface with 8, 12, 16 and 32-chan-nel APD arrays. The LTC6561 s fast overload recovery and fast channel switchover make it well suited for LIDAR receivers with multiple APDs. Its single-ended output can swing 2VP-P on a 100 load. While its low impedance op amp-style output can drive back-terminated 50 LTC6561 is packaged in a compact 4mm 4mm 24-pin leadless QFN package with an exposed pad for thermal management and low Application with DC-Coupled Inputs Driving a Time-to-Digital Converter with Back-Terminated CableAPPLICATIONS n220 MHz 3dB Bandwidth with 2pF Input Capacitance nSingle-Ended Output n74k Transimpedance Gain Hz Input Current Noise Density at 200 MHz (2pF) n64nARMS Integrated Input Current Noise Over 200 MHz (2pF)

3 NLinear Input Range 0 A to 30 A nOverload Current > 400mA Peak nFast Overload Recovery 12ns, 1mA nFast Channel Switchover < 50ns nSingle 5V Supply n200mW Power Dissipation for 4 Channels n2VP-P Output Swing on 100 Load n4mm 4mm, 24-Lead QFN Package nOutput MUX Combines Multiple 4-Channel Devices to Create 4, 8,12,16, 24, 32 Channel Solutions nAEC-Q100 Qualified for Automotive Applications nLIDAR Receiver nIndustrial ImagingAll registered trademarks and trademarks are the property of their respective Response at the Edge of the Overload Region (40 A)WITH SERIES 50 , INTO 50 LOAD,RTEFF = 37k OUTPUT RESPONSE( )INPUT PULSE(20 A/DIV)5ns/DIV6561 WIRE-ORMUXOUT(2)MULTIPLE LTC6561 s6561 50 CHSEL1,0O_MUXO_MUX(2)OUTLTC6561 VCC1,2 GNDIN1 VREF1IN2 VREF2IN3 VREF3IN4 TIATIATIATIAVREF44.

4 1 MUXGAINOUTTERMOUTPUTSTAGETIME-OF-FLIGHTD ETECTORAPD ARRAY 150V+ Document FeedbackLTC65612 Rev. CFor more information CONFIGURATIONABSOLUTE MAXIMUM RATINGST otal Supply Voltage (VCC1, VCC2, VCCO to GND) .. (CHSEL0, CHSEL1, O_MUX) .. to Reference Current (VREF1, VREF2, VREF3, VREF4) .. 10mAAmplifier Reference Voltage (VREF1, VREF2, VREF3, VREF4) .. to Input Current (IN1, IN2, IN3, IN4) .. 400mA RMS 2A Tr ansi en t (10ns) Amplifier Output Current (OUT, OUTTERM) ..+80mAOperating Temperature Range LTC6561I (Note 2).. 40 C to 85 C LTC6561H (Note 3).

5 40 C to 125 CStorage Temperature Range .. 65 C to 150 CJunction Temperature ..150 C(Note 1)242322212019789 TOP VIEWUF PACKAGE24-LEAD (4mm 4mm) PLASTIC QFNTJMAX = 150 C, JA = 47 C/W, JC = C/WEXPOSED PAD (PIN 25) IS GND, MUST BE SOLDERED TO PCB101112654321131415161718 VCCOCHSEL0 VCC1 VREF1 GNDIN1 VCCOO_MUXVCC2 VREF4 GNDIN425 GNDCHSEL1 OUTGNDGNDOUTTERMDNCIN2 GNDVREF2 VREF3 GNDIN3 ORDER INFORMATIONTUBETAPE AND REELPART MARKING*PACKAGE DESCRIPTIONTEMPERATURE RANGELTC6561 IUF#PBFLTC6561 IUF#TRPBF656124-LEAD (4mm 4mm) PLASTIC QFN 40 C to 85 CLTC6561 HUF#PBFLTC6561 HUF#TRPBF656124-LEAD (4mm 4mm)

6 PLASTIC QFN 40 C to 125 CAUTOMOTIVE PRODUCTS** LTC6561 HUF#WPBFLTC6561 HUF#WTRPBF656124-LEAD (4mm 4mm) PLASTIC QFN 40 C to 125 CConsult ADI Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping and reel specifications. Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.**Versions of this part are available with controlled manufacturing to support the quality and reliability requirements of automotive applications.

7 These models are designated with a #W suffix. Only the automotive grade products shown are available for use in automotive applications. Contact your local analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C.

8 VCC1,2 = VCC0 = 5V, O_MUX = 0V, GND = 0V, ZLOAD = 100 . Output is AC-coupled. Output taken from OUT 3dB Bandwidth200mVP-P,OUT and CIN,TOT = 2pF220 MHzRTSmall Signal TransimpedanceIIN < 2 AP-P l63 101k RINI nput Impedancef = 100kHz236 ROUTO utput Impedancef = 100kHz3 LTC65613 Rev. CFor more information The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C, VCC1,2 = VCC0 = 5V, O_MUX = 0V, GND = 0V, ZLOAD = 100.

9 Output is AC-coupled. Output taken from OUT ELECTRICAL CHARACTERISTICSSYMBOLPARAMETERCONDITIONS MINTYPMAXUNITSIN1,2,3,4 Pins and VREF1,2,3,4 PinsVINI nput Bias VoltageActive Channel Inactive Channel l V V VVREFI nput Reference VoltageActive Channel Inactive VOffsetVIN VREFA ctive Channel Inactive Channel 12 74112 116mV mVOUT PinVOUTO utput Default VoltageO_MUX = 0V O_MUX = , Standalone Device l V V VOVRO utput Voltage RangeIIN Current Range = 0 to 50 A VP-POUTTERMI nternal Series Resistor for Optional CHSEL0, CHSEL1, O_MUX Pins with Internal Pull-Down Voltage = A AIIHPin Voltage = l37 344757 62 A ACINI nput Resistance l22 212935 37k k SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSI nInput Current Noise Densityf = 100 MHz, CIN,TOT = Hzf = 200 MHz, CIN,TOT = HzIntegrated Input Current Noisef = to 100 MHz, CIN,TOT = 2pF43nARMSf = to 200 MHz, CIN.

10 TOT = 2pF64nARMSA djacent Channel to Channel Isolationf = 100 MHz 45dBNon Adjacent Channel Isolationf = 100 MHz 65dBtRECOVERO verload Recovery TimeInput Pulse = 1mA12nstSWITCHC hannel Switchover TimeDC Coupled Input50nstOMUX_SWITCHO utput MUX Switchover TimeDC Coupled Input50nsAC ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C, VCC1,2 = VCC0 = 5V, O_MUX = 0V, GND = 0V, ZLOAD = 100.