LT6233/LT6233-10 LT6234/LT6235 60MHz, Rail-to-Rail Output, 1.9nV/√Hz, 1.2mA Op Amp Family Features Description Low Noise Voltage: 1.9nV/√Hz n Low Supply Current: 1.2mA/Amp Max n Low Offset Voltage: 350µV Max n Gain-Bandwidth Product: LT6233: 60MHz; AV ≥ 1 LT6233-10: 375MHz; AV ≥ 10 n Wide Supply Range: 3V to 12.6V n Output Swings Rail-to-Rail n Common Mode Rejection Ratio: 115dB Typ n Output Current: 30mA n Operating Temperature Range: –40°C to 85°C n LT6233 Shutdown to 10µA Maximum n LT6233/LT6233-10 in a Low Profile (1mm) ThinSOT™ Package n Dual LT6234 in 8-Pin SO and Tiny DFN Packages n LT6235 in a 16-Pin SSOP Package The LT®6233/LT6234/LT6235 are single/dual/quad low noise, rail-to-rail output unity-gain stable op amps that feature 1.9nV/√Hz noise voltage and draw only 1.2mA of supply current per amplifier. These amplifiers combine very low noise and supply current with a 60MHz gainbandwidth product, a 17V/µs slew rate and are optimized for low supply voltage signal conditioning systems. The LT6233-10 is a single amplifier optimized for higher gain applications resulting in higher gain bandwidth and slew rate. The LT6233 and LT6233-10 include an enable pin that can be used to reduce the supply current to less than 10µA. n Applications n n n n n Ultrasound Amplifiers Low Noise, Low Power Signal Processing Active Filters Driving A/D Converters Rail-to-Rail Buffer Amplifiers The amplifier family has an output that swings within 50mV of either supply rail to maximize the signal dynamic range in low supply applications and is specified on 3.3V, 5V and ±5V supplies. The en • √ISUPPLY product of 2.1 per amplifier is among the most noise efficient of any op amp. The LT6233/LT6233-10 are available in the 6-lead SOT‑23 package and the LT6234 dual is available in the 8-pin SO package with standard pinouts. For compact layouts, the dual is also available in a tiny dual fine pitch leadless package (DFN). The LT6235 is available in the 16-pin SSOP package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application Noise Voltage and Unbalanced Noise Current vs Frequency Low Noise Low Power Instrumentation Amplifier 6 1/2 LT6234 R6 499Ω VS+ R2 475Ω + R1 49.9Ω LT6233 R3 475Ω 1/2 LT6234 IN– VS– 5 – R5 499Ω VOUT EN IS = 3mA EN = 8µVRMS INPUT REFERRED, MEASUREMENT BW = 4MHz 6 5 4 4 3 3 NOISE VOLTAGE 2 2 1 R7 VS– 499Ω 623345 TA01a AV = 20 BW = 2.8MHz VS = ±1.5V to ±5V NOISE VOLTAGE (nV/√Hz) R4 499Ω IN+ VS = ±2.5V TA = 25°C VCM = 0V 1 NOISE CURRENT 0 10 100 1k 10k FREQUENCY (Hz) UNBALANCED NOISE CURRENT (pA/√Hz) VS+ 0 100k 623345 TA01b 623345fc 1 LT6233/LT6233-10 LT6234/LT6235 Absolute Maximum Ratings (Note 1) Total Supply Voltage (V+ to V–)............................... 12.6V Input Current (Note 2).......................................... ±40mA Output Short-Circuit Duration (Note 3)............. Indefinite Operating Temperature Range (Note 4)....–40°C to 85°C Specified Temperature Range (Note 5).....–40°C to 85°C Junction Temperature............................................ 150°C Junction Temperature (DD Package)..................... 125°C Storage Temperature Range................... –65°C to 150°C Storage Temperature Range (DD Package)......................................... –65°C to 125°C Lead Temperature (Soldering, 10 sec).................... 300°C Pin Configuration TOP VIEW TOP VIEW 6 V+ OUT 1 V– 2 5 ENABLE +IN 3 4 –IN S6 PACKAGE 6-LEAD PLASTIC TSOT-23 TJMAX = 150°C, θJA = 250°C/W OUT A 1 –IN A 2 +IN A 3 V– 4 – + – + 8 V+ 7 OUT B 6 –IN B 5 +IN B DD PACKAGE 8-LEAD (3mm × 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 160°C/W UNDERSIDE METAL CONNECTED TO V– (PCB CONNECTION OPTIONAL) TOP VIEW OUT A 1 –IN A 2 +IN A 3 V– 4 – + – + 8 V+ 7 OUT B V 6 –IN B +IN B 5 +IN B –IN B 6 5 S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 190°C/W +IN A 3 + – + A 15 –IN D 14 +IN D D 4 OUT B 7 NC 8 OUT D – –IN A 2 OUT A 1 16 + TOP VIEW 13 V + –B + C– – 12 +IN C 11 –IN C 10 OUT C 9 NC GN PACKAGE 16-LEAD NARROW PLASTIC SSOP TJMAX = 150°C, θJA = 135°C/W 623345fc 2 LT6233/LT6233-10 LT6234/LT6235 Order Information LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT6233CS6#PBF LT6233CS6#TRPBF LTAFL 6-Lead Plastic TS0T-23 0°C to 70°C LT6233IS6#PBF LT6233IS6#TRPBF LTAFL 6-Lead Plastic TS0T-23 –40°C to 85°C LT6233CS6-10#PBF LT6233CS6-10#TRPBF LTAFM 6-Lead Plastic TS0T-23 0°C to 70°C LT6233IS6-10#PBF LT6233IS6-10#TRPBF LTAFM 6-Lead Plastic TS0T-23 –40°C to 85°C LT6234CS8#PBF LT6234CS8#TRPBF 6234 8-Lead Plastic SO 0°C to 70°C LT6234IS8#PBF LT6234IS8#TRPBF 6234I 8-Lead Plastic SO –40°C to 85°C LT6234CDD#PBF LT6234CDD#TRPBF LAET 8-Lead (3mm × 3mm) Plastic DFN 0°C to 70°C LT6234IDD#PBF LT6234IDD#TRPBF LAET 8-Lead (3mm × 3mm) Plastic DFN –40°C to 85°C LT6235CGN#PBF LT6235CGN#TRPBF 6235 16-Lead Narrow Plastic SSOP 0°C to 70°C LT6235IGN#PBF LT6235IGN#TRPBF 6235I 16-Lead Narrow Plastic SSOP –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ Electrical Characteristics ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER VOS IB IOS TA = 25°C, VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, TYP MAX UNITS 100 50 75 500 350 450 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) 80 600 µV Input Bias Current 1.5 3 µA IB Match (Channel-to-Channel) (Note 6) 0.04 0.3 µA Input Offset Current 0.04 0.3 µA Input Offset Voltage CONDITIONS MIN LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD Input Noise Voltage 0.1Hz to 10Hz 220 en Input Noise Voltage Density f = 10kHz, VS = 5V 1.9 nVP-P in Input Noise Current Density, Balanced Source Input Noise Current Density, Unbalanced Source f = 10kHz, VS = 5V, RS = 10k f = 10kHz, VS = 5V, RS = 10k 0.43 0.78 Input Resistance Common Mode Differential Mode 22 25 MΩ kΩ CIN Input Capacitance Common Mode Differential Mode 2.5 4.2 pF pF AVOL Large-Signal Gain VS = 5V, VO = 0.5V to 4.5V, RL = 10k to VS/2 VS = 5V, VO = 0.5V to 4.5V, RL = 1k to VS/2 73 18 140 35 V/mV V/mV VS = 3.3V, VO = 0.65V to 2.65V, RL = 10k to VS/2 VS = 3.3V, VO = 0.65V to 2.65V, RL = 1k to VS/2 53 11 100 20 V/mV V/mV 3 nV/√Hz pA/√Hz pA/√Hz VCM Input Voltage Range Guaranteed by CMRR, VS = 5V, 0V Guaranteed by CMRR, VS = 3.3V, 0V CMRR Common Mode Rejection Ratio VS = 5V, VCM = 1.5V to 4V VS = 3.3V, VCM = 1.15V to 2.65V 90 85 115 110 dB dB CMRR Match (Channel-to-Channel) (Note 6) VS = 5V, VCM = 1.5V to 4V 84 115 dB 1.5 1.15 4 2.65 V V 623345fc 3 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics ENABLE = 0V, unless otherwise noted. TA = 25°C, VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, SYMBOL PARAMETER CONDITIONS MIN TYP PSRR Power Supply Rejection Ratio PSRR Match (Channel-to-Channel) (Note 6) VS = 3V to 10V 90 115 dB VS = 3V to 10V 84 115 dB Minimum Supply Voltage (Note 7) MAX 3 UNITS V VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA VS = 5V, ISINK = 15mA VS = 3.3V, ISINK = 10mA 4 75 165 125 40 180 320 240 mV mV mV mV VOH Output Voltage Swing High (Note 8) No Load ISOURCE = 5mA VS = 5V, ISOURCE = 15mA VS = 3.3V, ISOURCE = 10mA 5 85 220 165 50 195 410 310 mV mV mV mV ISC Short-Circuit Current VS = 5V VS = 3.3V IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = V+ – 0.35V 1.05 0.2 1.2 10 mA µA IENABLE ENABLE Pin Current ENABLE = 0.3V –25 –75 µA VL ENABLE Pin Input Voltage Low 0.3 V 10 µA VH ±40 ±35 ±55 ±50 mA mA V+ – 0.35 ENABLE Pin Input Voltage High V Output Leakage Current ENABLE = V+ – 0.35V, VO = 1.5V to 3.5V 0.2 tON Turn-On Time ENABLE = 5V to 0V, RL = 1k, VS = 5V 500 ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k, VS = 5V 76 µs GBW Gain-Bandwidth Product Frequency = 1MHz, VS = 5V LT6233-10 55 320 MHz MHz SR Slew Rate VS = 5V, A V = –1, RL = 1k, VO = 1.5V to 3.5V 15 V/µs 80 V/µs 10 LT6233-10, VS = 5V, AV = –10, RL = 1k, VO = 1.5V to 3.5V FPBW tS Full-Power Bandwidth Settling Time (LT6233, LT6234, LT6235) 1.6 MHz LT6233-10, HD2 = HD3 ≤ 1% VS = 5V, VOUT = 3VP-P (Note 9) 1.06 2.2 MHz 0.1%, VS = 5V, VSTEP = 2V, AV = –1, RL = 1k 175 ns 623345fc 4 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics The l denotes the specifications which apply over the 0°C < TA < 70°C temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT6233CS6, LT6233CS6-10 LT6234CS8, LT6235CGN LT6234CDD Input Offset Voltage Match (Channel-to-Channel) (Note 6) VOS TC IB Input Offset Voltage Drift (Note 10) MIN TYP UNIT 600 450 550 µV µV µV l 800 µV 3.0 µV/°C 0.5 l Input Bias Current l 3.5 µA IB Match (Channel-to-Channel) (Note 6) l 0.4 µA IOS Input Offset Current AVOL Large-Signal Gain VCM VCM = Half Supply MAX l l l Input Voltage Range µA l l 47 12 V/mV V/mV VS = 3.3V, VO = 0.65V to 2.65V, RL = 10k to VS/2 l VS = 3.3V, VO = 0.65V to 2.65V, RL = 1k to VS/2 l 40 7.5 V/mV V/mV Guaranteed by CMRR VS = 5V, 0V Vs = 3.3V, 0V l l 1.5 1.15 VS = 5V, VCM = 1.5V to 4V VS = 3.3V, VCM = 1.15V to 2.65V l l 90 85 dB dB l 84 dB l 90 dB l 84 dB l 3 V CMRR Common Mode Rejection Ratio PSRR CMRR Match (Channel-to-Channel) (Note 6) VS = 5V, VCM = 1.5V to 4V Power Supply Rejection Ratio VS = 3V to 10V PSRR Match (Channel-to-Channel) (Note 6) 0.4 l VS = 5V, VO = 0.5V to 4.5V, RL = 10k to VS/2 VS = 5V, VO = 0.5V to 4.5V, RL = 1k to VS/2 VS = 3V to 10V Minimum Supply Voltage (Note 7) 4 2.65 V V VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA VS = 5V, ISINK = 15mA VS = 3.3V, ISINK = 10mA l l l l 50 195 360 265 mV mV mV mV VOH Output Voltage Swing High (Note 8) No Load ISOURCE = 5mA VS = 5V, ISOURCE = 15mA VS = 3.3V, ISOURCE = 10mA l l l l 60 205 435 330 mV mV mV mV ISC Short-Circuit Current VS = 5V VS = 3.3V l l IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = V+ – 0.25V l l IENABLE ENABLE Pin Current ENABLE = 0.3V l VL ENABLE Pin Input Voltage Low l VH ENABLE Pin Input Voltage High l ±35 ±30 mA mA 1 V+ – 0.25 1.45 mA µA –85 µA 0.3 V V Output Leakage Current ENABLE = V+ – 0.25V, VO = 1.5V to 3.5V l 1 µA tON Turn-On Time ENABLE = 5V to 0V, RL = 1k, VS = 5V l 500 ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k, VS = 5V l 120 µs SR Slew Rate VS = 5V, AV = –1, RL = 1k, VO = 1.5V to 3.5V l FPBW Full-Power Bandwidth (Note 9) VS = 5V, VOUT = 3VP-P; LT6233C, LT6234C, LT6235C 9 LT6233-10, AV = –10, RL = 1k, VO = 1.5V to 3.5V l l V/µs 75 955 V/µs kHz 623345fc 5 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics The l denotes the specifications which apply over the –40°C < TA < 85°C temperature range. VS = 5V, 0V; VS = 3.3V, 0V; VCM = VOUT = half supply, ENABLE = 0V, unless otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS MIN VOS Input Offset Voltage LT6233IS6, LT6233IS6-10 LT6234IS8, LT6235IGN LT6234IDD Input Offset Voltage Match (Channel-to-Channel) (Note 6) VOS TC Input Offset Voltage Drift (Note 10) IB Input Bias Current VCM = Half Supply MAX UNITS l l l 700 550 650 µV µV µV l 1000 µV 3 µV/°C l 4 µA 0.4 µA 0.5 µA IB Match (Channel-to-Channel) (Note 6) IOS Input Offset Current l AVOL Large-Signal Gain CMRR Input Voltage Range Common Mode Rejection Ratio VS = 5V, VO = 0.5V to 4.5V, RL = 10k to VS/2 VS = 5V, VO = 0.5V to 4.5V, RL = 1k to VS/2 l l 45 11 V/mV V/mV VS = 3.3V, VO = 0.65V to 2.65V, RL = 10k to VS/2 VS = 3.3V, VO = 0.65V to 2.65V, RL = 1k to VS/2 l l 38 7 V/mV V/mV Guaranteed by CMRR VS = 5V, 0V VS = 3.3V, 0V l l 1.5 1.15 VS = 5V, VCM = 1.5V to 4V VS = 3.3V, VCM = 1.15V to 2.65V l l 90 85 dB dB CMRR Match (Channel-to-Channel) (Note 6) VS = 5V, VCM = 1.5V to 4V PSRR 0.5 l l VCM TYP 4 2.65 V V l 84 dB Power Supply Rejection Ratio VS = 3V to 10V l 90 dB PSRR Match (Channel-to-Channel) (Note 6) VS = 3V to 10V l 84 dB l 3 Minimum Supply Voltage (Note 7) V VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA VS = 5V, ISINK = 15mA VS = 3.3V, ISINK = 10mA l l l l 50 195 370 275 mV mV mV mV VOH Output Voltage Swing High (Note 6) No Load ISOURCE = 5mA VS = 5V, ISOURCE = 15mA VS = 3.3V, ISOURCE = 10mA l l l l 60 210 445 335 mV mV mV mV ISC Short-Circuit Current VS = 5V VS = 3.3V l l IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = V+ – 0.2V l l IENABLE ENABLE Pin Current ENABLE = 0.3V VL ENABLE Pin Input Voltage Low VH tON ENABLE Pin Input Voltage High mA µA l –100 µA l 0.3 V l Output Leakage Current Turn-On Time ENABLE = 5V to 0V, RL = 1k, VS = 5V l 1 V+ – 0.2 1 µA 500 ns Turn-Off Time ENABLE = 0V to 5V, RL = 1k, VS = 5V l SR Slew Rate VS = 5V, AV = –1, RL = 1k, VO = 1.5V to 3.5V l 135 8 LT6233-10, AV = –10, RL = 1k, VO = 1.5V to 3.5V l Full-Power Bandwidth (Note 9) VS = 5V, VOUT = 3VP-P; LT6233I, LT6234I, LT6235I V l tOFF FPBW mA mA 1.5 ENABLE = V+ – 0.2V, V O = 1.5V to 3.5V ±30 ±20 l 70 848 µs V/µs V/µs kHz 623345fc 6 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics TA = 25°C, VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD IB IOS MIN TYP MAX UNITS 100 50 75 500 350 450 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) 100 600 µV Input Bias Current 1.5 3 µA IB Match (Channel-to-Channel) (Note 6) 0.04 0.3 µA Input Offset Current 0.04 0.3 µA 3.0 nV/√Hz Input Noise Voltage 0.1Hz to 10Hz 220 en Input Noise Voltage Density f = 10kHz 1.9 in Input Noise Current Density, Balanced Source Input Noise Current Density, Unbalanced Source f = 10kHz, RS = 10k f = 10kHz, RS = 10k 0.43 0.78 Input Resistance Common Mode Differential Mode 22 25 MΩ kΩ CIN Input Capacitance Common Mode Differential Mode 2.1 3.7 pF pF AVOL Large-Signal Gain VO = ±4.5V, RL = 10k VO = ±4.5V, RL = 1k 180 55 V/mV V/mV VCM Input Voltage Range Guaranteed by CMRR –3 CMRR Common Mode Rejection Ratio VCM = –3V to 4V 90 110 dB 97 28 nVP-P pA/√Hz pA/√Hz 4 V CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V 84 120 dB PSRR Power Supply Rejection Ratio VS = ±1.5V to ±5V 90 115 dB PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V 84 115 VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA ISINK = 15mA 4 75 165 40 180 320 mV mV mV VOH Output Voltage Swing High (Note 8) No Load ISOURCE = 5mA ISOURCE = 15mA 5 85 220 50 195 410 mV mV mV ISC Short-Circuit Current IS Supply Current per Amplifier Disabled Supply Current per Amplifier IENABLE ENABLE Pin Current VL ENABLE Pin Input Voltage Low VH ENABLE Pin Input Voltage High tON ±40 dB ±55 mA ENABLE = 4.65V 1.15 0.2 1.4 10 mA µA ENABLE = 0.3V –35 –85 µA 0.3 4.65 V V Output Leakage Current ENABLE = 4.65V, VO = ±1V 0.2 Turn-On Time ENABLE = 5V to 0V, RL = 1k 900 10 µA ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k 100 µs GBW Gain-Bandwidth Product Frequency = 1MHz LT6233-10 42 260 60 375 MHz MHz SR Slew Rate AV = –1, RL = 1k, VO = –2V to 2V 12 17 V/µs FPBW Full-Power Bandwidth VOUT = 3VP-P (Note 9) tS Settling Time (LT6233, LT6234, LT6235) LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V 115 V/µs 1.8 MHz LT6233-10, HD2 = HD3 ≤ 1% 2.2 MHz 0.1%, VSTEP = 2V, AV = –1, RL = 1k 170 ns 1.27 623345fc 7 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics The l denotes the specifications which apply over the 0°C < TA < 70°C temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT6233CS6, LT6233CS6-10 LT6234CS8, LT6235CGN LT6234CDD MIN TYP MAX UNITS l l l 600 450 550 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) l 800 µV VOS TC Input Offset Voltage Drift (Note 10) l IB Input Bias Current l 3.5 µA IB Match (Channel-to-Channel) (Note 6) l 0.4 µA IOS Input Offset Current l 0.4 µA AVOL Large-Signal Gain VO = ±4.5V, RL = 10k VO = ±4.5V, RL = 1k l l 75 22 VCM Input Voltage Range Guaranteed by CMRR l –3 CMRR Common Mode Rejection Ratio VCM = –3V to 4V l 90 dB CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V l 84 dB PSRR Power Supply Rejection Ratio VS = ±1.5V to ±5V l 90 dB PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V l 84 VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA ISINK = 15mA l l l 50 195 360 mV mV mV VOH Output Voltage Swing High (Note 8) No Load ISOURCE = 5mA ISOURCE = 15mA l l l 60 205 435 mV mV mV ISC Short-Circuit Current l IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = 4.75V l l 1.7 mA µA IENABLE ENABLE Pin Current ENABLE = 0.3V l –95 µA VL ENABLE Pin Input Voltage Low l 0.3 V VH ENABLE Pin Input Voltage High l 0.5 3 µV/°C V/mV V/mV 4 V dB ±35 mA 1 4.75 V Output Leakage Current ENABLE = 4.75V, VO = ±1V l 1 µA tON Turn-On Time ENABLE = 5V to 0V, RL = 1k l 900 ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k l 150 µs SR Slew Rate AV = –1, RL = 1k, VO = –2V to 2V l LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V l VOUT = 3VP-P ; LT6233C, LT6234C, LT6235C l FPBW Full-Power Bandwidth (Note 9) 11 V/µs 105 1.16 V/µs MHz 623345fc 8 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics The l denotes the specifications which apply over the –40°C < TA < 85°C temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS MIN VOS Input Offset Voltage LT6233IS6, LT6233IS6-10 LT6234IS8, LT6235IGN LT6234IDD TYP MAX UNITS l l l 700 550 650 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) l 1000 µV VOS TC Input Offset Voltage Drift (Note 10) l 3 µV/°C IB Input Bias Current l 4 µA 0.5 IB Match (Channel-to-Channel) (Note 6) l 0.4 µA IOS Input Offset Current l 0.5 µA AVOL Large-Signal Gain VO = ±4.5V, RL = 10k VO = ±4.5V, RL = 1k l l 68 20 VCM Input Voltage Range Guaranteed by CMRR l –3 CMRR Common Mode Rejection Ratio VCM = –3V to 4V l 90 dB CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V l 84 dB dB PSRR Power Supply Rejection Ratio VS = ±1.5V to ±5V l 90 84 V/mV V/mV 4 V PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V l VOL Output Voltage Swing Low (Note 8) No Load ISINK = 5mA ISINK = 15mA l l l 50 195 370 mV mV mV dB VOH Output Voltage Swing High (Note 8) No Load ISOURCE = 5mA ISOURCE = 15mA l l l 70 210 445 mV mV mV ISC Short-Circuit Current l IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = 4.8V l l IENABLE ENABLE Pin Current ENABLE = 0.3V l VL ENABLE Pin Input Voltage Low l VH ENABLE Pin Input Voltage High l ±30 mA 1 4.8 1.75 mA µA –110 µA 0.3 V V Output Leakage Current ENABLE = 4.8V, VO = ±1V l 1 µA tON Turn-On Time ENABLE = 5V to 0V, RL = 1k l 900 ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k l 160 µs SR Slew Rate AV = –1, RL = 1k, VO = –2V to 2V l LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V l VOUT = 3VP-P; LT6233I, LT6234I, LT6235I l FPBW Full-Power Bandwidth (Note 9) Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Inputs are protected by back-to-back diodes. If the differential input voltage exceeds 0.7V, the input current must be limited to less than 40mA. Note 3: A heat sink may be required to keep the junction temperature below the absolute maximum rating when the output is shorted indefinitely. Note 4: The LT6233C/LT6233I the LT6234C/LT6234I, and LT6235C/LT6235I are guaranteed functional over the temperature range of –40°C to 85°C. 10 V/µs 95 1.06 V/µs MHz Note 5: The LT6233C/LT6234C/LT6235C are guaranteed to meet specified performance from 0°C to 70°C. The LT6233C/LT6234C/LT6235C are designed, characterized and expected to meet specified performance from –40°C to 85°C, but are not tested or QA sampled at these temperatures. The LT6233I/LT6234I/LT6235I are guaranteed to meet specified performance from –40°C to 85°C. Note 6: Matching parameters are the difference between the two amplifiers A and D and between B and C of the LT6235; between the two amplifiers of the LT6234. CMRR and PSRR match are defined as follows: CMRR and PSRR are measured in µV/V on the matched amplifiers. The difference is calculated between the matching sides in µV/V. The result is converted to dB. 623345fc 9 LT6233/LT6233-10 LT6234/LT6235 Electrical Characteristics Note 7: Minimum supply voltage is guaranteed by power supply rejection ratio test. Note 8: Output voltage swings are measured between the output and power supply rails. Note 9: Full-power bandwidth is calculated from the slew rate: FPBW = SR/2πVP Note 10: This parameter is not 100% tested. Typical Performance Characteristics (LT6233/LT6234/LT6235) Supply Current vs Supply Voltage (Per Amplifier) VOS Distribution 2.0 60 VS = 5V, 0V VCM = V+/2 50 S8 500 400 40 30 20 VS = 5V, 0V 300 TA = 125°C 1.5 OFFSET VOLTAGE (µV) SUPPLY CURRENT (mA) NUMBER OF UNITS Offset Voltage vs Input Common Mode Voltage TA = 25°C 1.0 TA = –55°C 0.5 200 100 0 –100 TA = –55°C –200 –300 10 TA = 25°C –400 0 50 100 150 200 –200 –150 –100 –50 0 INPUT OFFSET VOLTAGE (µV) 0 2 0 10 12 8 6 TOTAL SUPPLY VOLTAGE (V) 4 Input Bias Current vs Common Mode Voltage TA = –55°C TA = 125°C 1 TA = 25°C 0 4 3 2 VCM = 4V 1 VCM = 1.5V 0 –1 –2 10 VS = 5V, 0V 5 INPUT BIAS CURRENT (µA) INPUT BIAS CURRENT (µA) 5 2 –1 0 4 5 3 2 COMMON MODE VOLTAGE (V) 1 Output Saturation Voltage vs Load Current (Output Low) OUTPUT SATURATION VOLTAGE (V) 6 VS = 5V, 0V 3 623345 GO3 Input Bias Current vs Temperature 4 6 623345 GO4 TA = 125°C 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 INPUT COMMON MODE VOLTAGE (V) 623345 GO2 623345 GO1 6 –500 14 –1 –50 –25 0 50 75 25 TEMPERATURE (°C) 100 125 623345 GO5 VS = 5V, 0V 1 TA = 125°C 0.1 TA = –55°C 0.01 TA = 25°C 0.001 0.0001 0.01 10 0.1 1 LOAD CURRENT (mA) 100 623345 GO6 623345fc 10 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233/LT6234/LT6235) Output Saturation Voltage vs Load Current (Output High) 1.0 80 VCM = VS/2 0.8 0.6 1 TA = 125°C 0.1 TA = –55°C 0.01 0.01 0.4 0.2 0 –0.2 TA = –55°C –0.4 –0.6 TA = 25°C 0.001 TA = 25°C –0.8 0.1 1 10 LOAD CURRENT (mA) –1.0 100 TA = 125°C 2.0 –20 RL = 100Ω –1.0 0.5 RL = 1k 0 RL = 100Ω –0.5 –1.0 –0.5 Offset Voltage vs Output Current 40 0 –0.5 –1.0 –1.5 –2.0 –90 TA = –55°C TA = 25°C –60 –30 0 30 60 90 OUTPUT CURRENT (mA) 623345 G13 4 100 TA = 25°C 35 VS = ±5V 30 25 VS = ±2.5V 20 15 5 Total Noise vs Total Source Resistance TOTAL NOISE (nV/√Hz) CHANGE IN OFFSET VOLTAGE (µV) 0.5 –5 –4 –3 –2 –1 0 1 2 3 OUTPUT VOLTAGE (V) 623345 G12 Warm-Up Drift vs Time VS = ±5V 1.0 –2.5 623345 G11 623345 G10 TA = 125°C RL = 100Ω –1.0 –2.0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 OUTPUT VOLTAGE (V) RL = 1k 0 –2.5 1.5 VS = ±5V TA = 25°C 0.5 –2.5 3.0 5.0 1.0 –1.5 2.0 2.5 3.0 3.5 4.0 4.5 POWER SUPPLY VOLTAGE (±V) 2.0 1.5 1.0 –2.0 2.5 TA = 25°C 2.0 –1.5 1.0 1.5 2.0 OUTPUT VOLTAGE (V) TA = –55°C –60 –2.0 0.5 TA = 125°C –40 –1.5 0 SOURCING Open-Loop Gain INPUT VOLTAGE (mV) INPUT VOLTAGE (mV) INPUT VOLTAGE (mV) RL = 1k –0.5 0 2.5 1.5 0 TA = 25°C 623345 GO9 VS = 5V, 0V TA = 25°C 2.0 1.5 1.0 TA = 125°C SINKING 20 Open-Loop Gain 2.5 VS = 3V, 0V TA = 25°C 0.5 40 623345 G08 Open-Loop Gain 2.5 TA = –55°C 60 –80 1.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 TOTAL SUPPLY VOLTAGE (V) 623345 G07 OFFSET VOLTAGE (mV) OUTPUT SHORT-CIRCUIT CURRENT (mA) VS = 5V, 0V OFFSET VOLTAGE (mV) OUTPUT SATURATION VOLTAGE (V) 10 Output Short-Circuit Current vs Power Supply Voltage Minimum Supply Voltage VS = ±1.5V VS = ±2.5V VCM = 0V f = 100kHz UNBALANCED SOURCE 10 RESISTORS TOTAL NOISE RESISTOR NOISE AMPLIFIER NOISE VOLTAGE 1 10 0 0 10 30 40 20 TIME AFTER POWER-UP (s) 50 623345 G14 0.1 10 100 1k 10k TOTAL SOURCE RESISTANCE (Ω) 100k 623345 G15 623345fc 11 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233/LT6234/LT6235) Noise Voltage and Unbalanced Noise Current vs Frequency 4 3 3 NOISE VOLTAGE 2 1 1 NOISE CURRENT 0 100 10 100nV –100nV 623345 G16 GAIN (dB) 60 VS = ±5V 40 30 20 20 0 VS = 3V, 0V 10 0 VS = ±5V –20 –40 GAIN –10 –20 100k 1M PHASE (DEG) VS = 3V, 0V 40 10M 100M FREQUENCY (Hz) 1G PHASE MARGIN 22 GAIN BANDWIDTH 50 40 –80 30 2 0 10 12 8 6 TOTAL SUPPLY VOLTAGE (V) 4 AV = 2 AV = 1 1 1M 10M FREQUENCY (Hz) 100M 623345 G22 16 VS = ±2.5V RISING 10 –55 –35 –15 14 VS = ±5V FALLING VS = ±2.5V FALLING 14 5 25 45 65 85 105 125 TEMPERATURE (°C) 623345 G21 Common Mode Rejection Ratio vs Frequency Channel Separation vs Frequency –40 100 80 60 40 20 125 18 12 CHANNEL SEPARATION (dB) AV = 10 20 VS = ±5V RISING 623345 G20 COMMON MODE REJECTION RATIO (dB) OUTPUT IMPEDANCE (Ω) 60 60 –60 VS = 5V, 0V 0.1 100k AV = –1 24 RF = RG = 1k 120 10 95 26 70 40 Output Impedance vs Frequency 100 65 35 5 TEMPERATURE (°C) Slew Rate vs Temperature 50 70 623345 G19 1k –25 623345 G18 PHASE MARGIN (DEG) 50 VS = 3V, 0V 80 TA = 25°C CL = 5pF RL = 1k GAIN BANDWIDTH (MHz) CL = 5pF RL = 1k 100 VCM = VS/2 80 PHASE 60 40 GAIN BANDWIDTH VS = ±5V 60 Gain Bandwidth and Phase Margin vs Supply Voltage 120 70 CL = 5pF 80 RL = 1k VCM = VS/2 70 50 PHASE MARGIN 623345 G17 Open-Loop Gain vs Frequency 80 90 40 –55 5s/DIV 60 VS = 3V, 0V 50 0 100k 1k 10k FREQUENCY (Hz) VS = ±5V SLEW RATE (V/µs) 2 70 VS = ±2.5V PHASE MARGIN (DEG) 4 Gain Bandwidth and Phase Margin vs Temperature GAIN BANDWIDTH (MHz) 5 UNBALANCED NOISE CURRENT (pA/√Hz) 5 NOISE VOLTAGE (nV/√Hz) 6 VS = ±2.5V TA = 25°C VCM = 0V 100nV/DIV 6 0.1Hz to 10Hz Output Voltage Noise 100k –70 –80 –90 –100 –110 –120 –130 VS = 5V, 0V VCM = VS/2 0 10k AV = 1 –50 TA = 25°C VS = ±5V –60 1M 10M FREQUENCY (Hz) 100M 1G 623345 G23 –140 100k 1M 10M FREQUENCY (Hz) 100M 623345 G24 623345fc 12 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233/LT6234/LT6235) Power Supply Rejection Ratio vs Frequency 80 POSITIVE SUPPLY 60 40 NEGATIVE SUPPLY 50 VS = 5V, 0V 45 AV = 1 VS = 5V, 0V 45 AV = 2 RS = 10Ω 40 35 RS = 20Ω 30 25 20 RS = 50Ω RL = 50Ω 15 10 20 35 25 15 1M 100k FREQUENCY (Hz) 10M 100M 5 100 CAPACITIVE LOAD (pF) 10 Settling Time vs Output Step (Noninverting) 400 350 – + VIN 250 500Ω 200 1mV 10mV 150 1mV 300 SETTLING TIME (ns) SETTLING TIME (ns) VOUT 10mV – VOUT + 250 200 1mV 1mV 10mV 150 100 50 500Ω VIN 10mV 100 –3 –4 –2 –1 1 2 0 OUTPUT STEP (V) 3 50 4 –3 –4 –2 –1 1 2 0 OUTPUT STEP (V) 623345 G28 Distortion vs Frequency RL = 100Ω, 3RD –80 –90 –100 10k RL = 1k, 2ND 100k 1M FREQUENCY (Hz) –60 –70 RL = 100Ω, 2ND RL = 100Ω, 3RD 7 6 5 4 V = ±5V 3 T S = 25°C A HD2, HD3 < –40dBc 2 100k 1M 10k FREQUENCY (Hz) 623345 G31 10M Distortion vs Frequency –30 VS = ±2.5V A =2 –40 VV = 2V P-P OUT RL = 1k, 3RD –80 –90 10M AV = –1 8 623345 G30 VS = ±5V AV = 1 –50 VOUT = 2VP-P RL = 1k, 3RD AV = 2 9 Distortion vs Frequency DISTORTION (dBc) –70 4 –40 VS = ±2.5V AV = 1 –50 VOUT = 2VP-P –60 RL = 100Ω, 2ND 3 10 623345 G29 –40 DISTORTION (dBc) Maximum Undistorted Output Signal vs Frequency VS = ±5V TA = 25°C AV = –1 500Ω –100 10k 1000 623345 G27 Settling Time vs Output Step (Inverting) 400 300 100 CAPACITIVE LOAD (pF) 10 623345 G26 623345 G25 VS = ±5V TA = 25°C 350 AV = 1 0 1000 OUTPUT VOLTAGE SWING (VP-P) 10k RS = 50Ω RL = 50Ω 20 10 RL = 1k, 2ND DISTORTION (dBc) 1k 0 RS = 20Ω 30 5 0 RS = 10Ω 40 OVERSHOOT (%) 100 Series Output Resistance and Overshoot vs Capacitive Load 50 VS = 5V, 0V TA = 25°C VCM = VS/2 OVERSHOOT (%) POWER SUPPLY REJECTION RATIO (dB) 120 Series Output Resistance and Overshoot vs Capacitive Load –50 –60 RL = 1k, 3RD RL = 100Ω, 2ND RL = 100Ω, 3RD –70 –80 RL = 1k, 2ND –90 100k 1M FREQUENCY (Hz) 10M 623345 G32 –100 10k 100k 1M FREQUENCY (Hz) 10M 623345 G33 623345fc 13 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233/LT6234/LT6235) Distortion vs Frequency Large-Signal Response Small-Signal Response –30 RL = 1k, 3RD 2V –60 RL = 100Ω, 2ND RL = 100Ω, 3RD –70 50mV/DIV –50 1V/DIV DISTORTION (dBc) VS = ±5V A =2 –40 VV = 2V P-P OUT 0V 0V –2V –80 RL = 1k, 2ND –90 –100 10k 100k 1M FREQUENCY (Hz) 10M 623345 G35 200ns/DIV VS = ±2.5V AV = –1 RL = 1k VS = ±2.5V AV = 1 RL = 1k 200ns/DIV 623345 G36 623345 G34 Large-Signal Response Output Overdrive Recovery –5V 0V 0V 623345 G37 200ns/DIV VS = ±5V AV = 1 RL = 1k VIN 1V/DIV 0V VOUT 2V/DIV 2V/DIV 5V VS = ±2.5V AV = 3 200ns/DIV 623345 G38 (LT6233) ENABLE Characteristics Supply Current vs ENABLE Pin Voltage 1.0 TA = –55°C 0.8 30 ENABLE PIN CURRENT (µA) SUPPLY CURRENT (mA) TA = 25°C 0.6 0.4 25 TA = –55°C ENABLE Pin Response Time VS = ±2.5V AV = 1 ENABLE TA = 125°C 1.2 TA = 25°C VS = ±2.5V –2.0 0 1.0 –1.0 PIN VOLTAGE (V) 2.0 623345 G39 5V 0V 20 15 TA = 125°C 10 5 0.2 0 35 VOUT 1.4 ENABLE Pin Current vs ENABLE Pin Voltage 0 –2.0 0 1.0 –1.0 PIN VOLTAGE (V) 2.0 0.5V 0V VS = ±2.5V VIN = 0.5V AV = 1 RL = 1k 200µs/DIV 623345 G41 623345 G40 623345fc 14 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233-10) Gain Bandwidth and Phase Margin vs Temperature 200 GAIN BANDWIDTH (MHz) GAIN BANDWIDTH 300 VS = 3V, 0V 250 200 VS = ±5V 70 PHASE MARGIN 75 50 25 TEMPERATURE (°C) 80 VS = ±2.5V RISING 60 40 50 20 60 VS = 3V, 0V 40 20 VS = 3V, 0V 20 10 0 –20 VS = ±5V 0 –40 –10 TA = 25°C AV = 10 375 CL = 5pF RL = 1k 1M 10M 100M FREQUENCY (Hz) 1G GAIN BANDWIDTH 225 100 PHASE MARGIN 50 –80 0 2 4 8 10 6 TOTAL SUPPLY VOLTAGE (V) 623345 G45 60 40 20 100k 1M 10M FREQUENCY (Hz) 100M 200 150 100 50 0 0 0 1G 623345 G48 1000 400 800 600 TOTAL RESISTOR LOAD (Ω) (INCLUDES FEEDBACK R) 623345 G47 200 2nd and 3rd Harmonic Distortion vs Frequency 10 –30 8 VS = ±2.5V A = 10 –40 VV = 2V P-P OUT 7 –50 9 OUTPUT VOLTAGE SWING (VP-P) COMMON MODE REJECTION RATIO (dB) 80 0 10k 250 Maximum Undistorted Output vs Frequency VS = 5V, 0V VCM = VS/2 100 12 300 623345 G46 Common Mode Rejection Ratio vs Frequency 120 ASV = ±5V 10 V TA = 25°C RF = 1k RG = 100Ω 350 300 6 5 4 3 2 VS = ±5V TA = 25°C 1 AV = 10 HD2, HD3 ≤ 40dBc 0 100k 1M 10k FREQUENCY (Hz) 10000 Gain Bandwidth vs Resistor Load 400 –60 –20 100k 100 1000 CAPACITIVE LOAD (pF) 10 623345 G44 DISTORTION (dBc) GAIN (dB) 30 AV = 10 CL = 5pF 100 RL = 1k VCM = VS/2 80 PHASE (DEG) GAIN 40 0 5 25 45 65 85 105 125 TEMPERATURE (°C) PHASE MARGIN (DEG) VS = ±5V 50 20 450 GAIN BANDWIDTH (MHz) 60 RS = 50Ω Gain Bandwidth and Phase Margin vs Supply Voltage 120 PHASE 30 623345 G43 Open-Loop Gain and Phase vs Frequency 70 RS = 20Ω 40 10 623345 G42 80 RS = 10Ω 50 VS = ±2.5V FALLING 0 –55 –35 –15 125 VS = 5V, 0V AV = 10 60 VS = ±5V FALLING 100 40 100 0 70 120 60 VS = 3V, 0V –50 –25 PHASE MARGIN (DEG) 350 AV = –10 180 RF = 1k RG = 100Ω 160 VS = ±5V RISING 140 OVERSHOOT (%) VS = ±5V GAIN BANDWIDTH (MHz) AV = 10 400 SLEW RATE (V/µs) 450 Series Output Resistor and Overshoot vs Capacitive Load Slew Rate vs Temperature RL = 100Ω, 3RD –60 RL = 1k, 3RD RL = 100Ω, 2ND RL = 1k, 2ND –70 –80 –90 10M 623345 G49 –100 10k 100k 1M FREQUENCY (Hz) 10M 623345 G50 623345fc 15 LT6233/LT6233-10 LT6234/LT6235 Typical Performance Characteristics (LT6233-10) 2nd and 3rd Harmonic Distortion vs Frequency Large-Signal Response Output-Overload Recovery –30 RL = 100Ω, 2ND –60 0V 0V 0V RL = 1k, 3RD –70 –80 –90 –100 10k VOUT 2V/DIV RL = 1k, 2ND RL = 100Ω, 3RD VIN 0.5V/DIV –50 VOUT 2V/DIV DISTORTION (dBc) VS = ±5V A = 10 –40 VV = 2V P-P OUT 100k 1M FREQUENCY (Hz) 10M VS = ±5V AV = 10 RF = 900Ω RG = 100Ω 623345 G52 100ns/DIV VS = 5V, 0V AV = 10 RF = 900Ω RG = 100Ω 100ns/DIV 623345 G53 623345 G51 Input Referred High Frequency Noise Spectrum Small-Signal Response 1nV/√Hz/DIV VOUT 100mV/DIV 10 2.5V VS = 5V, 0V AV = 10 RF = 900Ω RG = 100Ω 100ns/DIV 623345 G54 0 100kHz 2MHz/DIV 20MHz 623345 G55 623345fc 16 LT6233/LT6233-10 LT6234/LT6235 Applications Information Figure 1 is a simplified schematic of the LT6233/LT6234/ LT6235, which has a pair of low noise input transistors Q1 and Q2. A simple current mirror Q3/Q4 converts the differential signal to a single-ended output, and these transistors are degenerated to reduce their contribution to the overall noise. Capacitor C1 reduces the unity-cross frequency and improves the frequency stability without degrading the gain bandwidth of the amplifier. Capacitor CM sets the overall amplifier gain bandwidth. The differential drive generator supplies current to transistors Q5 and Q6 that swing the output from rail-to-rail. Input Protection There are back-to-back diodes, D1 and D2 across the + and – inputs of these amplifiers to limit the differential input voltage to ±0.7V. The inputs of the LT6233/LT6234/LT6235 do not have internal resistors in series with the input transistors. This technique is often used to protect the input devices from overvoltage that causes excessive current to flow. The addition of these resistors would significantly degrade the low noise voltage of these amplifiers. For instance, a 100Ω resistor in series with each input would generate 1.8nV/√Hz of noise, and the total amplifier noise voltage would rise from 1.9nV/√Hz to 2.6nV/√Hz. Once the input differential voltage exceeds ±0.7V, steady-state current conducted through the protection diodes should be limited to ±40mA. This implies 25Ω of protection resistance is necessary per volt of overdrive beyond ±0.7V. These input diodes are rugged enough to handle transient currents due to amplifier slew rate overdrive and clipping without protection resistors. The photo of Figure 2 shows the output response to an input overdrive with the amplifier connected as a voltage follower. With the input signal low, current source I1 saturates and the differential drive generator drives Q6 into saturation so the output voltage swings all the way to V–. The input can swing positive until transistor Q2 saturates into current mirror Q3/Q4. When saturation occurs, the output tries to phase invert, but diode D2 conducts current from the signal source to the output through the feedback connection. The output is clamped a diode drop below the input. In this photo, the input signal generator is limiting at about 20mA. 2.5V 1V/DIV Amplifier Characteristics 0V –2.5V 500µs/DIV 623345 F02 Figure 2. VS = ±2.5V, AV = 1 with Large Overdrive +V Q3 –V +V DESD1 Q4 C1 DESD2 Q1 D1 DESD5 VOUT DESD6 DIFFERENTIAL DRIVE GENERATOR –V –VIN Q5 CM +V –V Q2 Q6 D2 +V +VIN DESD3 DESD4 –V I1 BIAS ENABLE +V –V 623345 F01 Figure 1. Simplified Schematic 623345fc 17 LT6233/LT6233-10 LT6234/LT6235 Applications Information With the amplifier connected in a gain of AV ≥ 2, the output can invert with very heavy overdrive. To avoid this inversion, limit the input overdrive to 0.5V beyond the power supply rails. ESD The LT6233/LT6234/LT6235 have reverse-biased ESD protection diodes on all inputs and outputs as shown in Figure 1. If these pins are forced beyond either supply, unlimited current will flow through these diodes. If the current is transient and limited to one hundred milliamps or less, no damage to the device will occur. Noise The noise voltage of the LT6233/LT6234/LT6235 is equivalent to that of a 225Ω resistor, and for the lowest possible noise it is desirable to keep the source and feedback resistance at or below this value, i.e., RS + RG||RFB ≤ 225Ω. With RS + RG||RFB = 225Ω the total noise of the amplifier is: eN = √(1.9nV)2 + (1.9nV)2 = 2.69nV/√Hz Below this resistance value, the amplifier dominates the noise, but in the region between 225Ω and about 30k, the noise is dominated by the resistor thermal noise. As the total resistance is further increased beyond 30k, the amplifier noise current multiplied by the total resistance eventually dominates the noise. The product of eN • √ISUPPLY is an interesting way to gauge low noise amplifiers. Most low noise amplifiers with low eN have high ISUPPLY current. In applications that require low noise voltage with the lowest possible supply current, this product can prove to be enlightening. The LT6233/LT6234/LT6235 have an eN • √ISUPPLY product of only 2.1 per amplifier, yet it is common to see amplifiers with similar noise specifications to have eN • √ISUPPLY as high as 13.5. For a complete discussion of amplifier noise, see the LT1028 data sheet. Enable Pin The LT6233 and LT6233-10 include an ENABLE pin that shuts down the amplifier to 10µA maximum supply current. The ENABLE pin must be driven low to operate the amplifier with normal supply current. The ENABLE pin must be driven high to within 0.35V of V+ to shut down the supply current. This can be accomplished with simple gate logic; however care must be taken if the logic and the LT6233 operate from different supplies. If this is the case, then open-drain logic can be used with a pull-up resistor to ensure that the amplifier remains off. See Typical Performance Characteristics. The output leakage current when disabled is very low; however, current can flow into the input protection diodes D1 and D2 if the output voltage exceeds the input voltage by a diode drop. 623345fc 18 LT6233/LT6233-10 LT6234/LT6235 Typical Applications Single Supply, Low Noise, Low Power, Bandpass Filter with Gain = 10 R1 732Ω Frequency Response Plot of Bandpass Filter C2 47pF f0 = V+ 23 1 = 1MHz 2πRC C = √C1,C2 R = R1 = R2 VIN R2 732Ω ( 0.1µF R3 10k – LT6233 + C3 0.1µF VOUT EN R4 10k ) f0 = 732Ω MHz, MAXIMUM f0 = 1MHz R f–3dB = f0 2.5 AV = 20dB at f0 EN = 6µVRMS INPUT REFERRED IS = 1.5mA FOR V+ = 5V GAIN (dB) C1 1000pF 3 623345 F03 –7 100k 1M FREQUENCY (Hz) 10M 623345 F04 Low Power, Low Noise, Single Supply, Instrumentation Amplifier with Gain = 100 R1 30.9Ω C2 2200pF R2 V+ 511Ω C8 68pF – U1 LT6233-10 + VIN1 C1 1µF EN R15 88.7Ω R13 2k – R6 511Ω R3 30.9Ω R5 511Ω R4 V+ 511Ω U2 LT6233-10 + VIN2 C3 1µF R16 88.7Ω R12 511Ω R14 2k – EN V+ R10 511Ω + C9 68pF U3 LT6233 VOUT EN C4 10µF VOUT = 100 (VIN2 – VIN1) ( )( ) GAIN = R2 + 1 R1 R10 R15 INPUT RESISTANCE = R5 = R6 f–3dB = 310Hz TO 2.5MHz EN = 10µVRMS INPUT REFERRED IS = 4.7mA FOR VS = 5V, 0V R1 = R3 R2 = R4 R10 = R12 R15 = R16 623345 F05 623345fc 19 LT6233/LT6233-10 LT6234/LT6235 Package Description S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 0.62 MAX 2.90 BSC (NOTE 4) 0.95 REF 1.22 REF 3.85 MAX 2.62 REF 1.4 MIN 2.80 BSC 1.50 – 1.75 (NOTE 4) PIN ONE ID RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.30 – 0.45 6 PLCS (NOTE 3) 0.95 BSC 0.80 – 0.90 0.20 BSC 0.01 – 0.10 1.00 MAX DATUM ‘A’ 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 1.90 BSC S6 TSOT-23 0302 623345fc 20 LT6233/LT6233-10 LT6234/LT6235 Package Description DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698 Rev C) 0.70 ±0.05 3.5 ±0.05 1.65 ±0.05 2.10 ±0.05 (2 SIDES) PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF 3.00 ±0.10 (4 SIDES) R = 0.125 TYP 5 0.40 ± 0.10 8 1.65 ± 0.10 (2 SIDES) 0.75 ±0.05 4 0.25 ± 0.05 1 (DD8) DFN 0509 REV C 0.50 BSC 2.38 ±0.10 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON TOP AND BOTTOM OF PACKAGE 623345fc 21 LT6233/LT6233-10 LT6234/LT6235 Package Description S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .189 – .197 (4.801 – 5.004) NOTE 3 .045 ±.005 .050 BSC 7 8 .245 MIN .160 ±.005 5 6 .150 – .157 (3.810 – 3.988) NOTE 3 .228 – .244 (5.791 – 6.197) .030 ±.005 TYP 1 RECOMMENDED SOLDER PAD LAYOUT .010 – .020 × 45° (0.254 – 0.508) 3 2 4 .053 – .069 (1.346 – 1.752) .008 – .010 (0.203 – 0.254) .004 – .010 (0.101 – 0.254) 0°– 8° TYP .016 – .050 (0.406 – 1.270) .050 (1.270) BSC .014 – .019 (0.355 – 0.483) TYP NOTE: 1. DIMENSIONS IN INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) SO8 0303 GN Package 16-Lead Plastic SSOP (Narrow .150 Inch) (Reference LTC DWG # 05-08-1641) .189 – .196* (4.801 – 4.978) .045 ±.005 16 15 14 13 12 11 10 9 .254 MIN .009 (0.229) REF .150 – .165 .229 – .244 (5.817 – 6.198) .0165 ±.0015 .150 – .157** (3.810 – 3.988) .0250 BSC RECOMMENDED SOLDER PAD LAYOUT 1 .015 ± .004 × 45° (0.38 ± 0.10) .007 – .0098 (0.178 – 0.249) 4 5 6 7 8 .004 – .0098 (0.102 – 0.249) 0° – 8° TYP .016 – .050 (0.406 – 1.270) NOTE: 1. CONTROLLING DIMENSION: INCHES INCHES 2. DIMENSIONS ARE IN (MILLIMETERS) 3. DRAWING NOT TO SCALE *DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 22 .0532 – .0688 (1.35 – 1.75) 2 3 .008 – .012 (0.203 – 0.305) TYP .0250 (0.635) BSC GN16 (SSOP) 0204 623345fc LT6233/LT6233-10 LT6234/LT6235 Revision History (Revision history begins at Rev C) REV DATE DESCRIPTION PAGE NUMBER C 1/11 Revised y-axis lable on curve G40 in Typical Performance Characteristics 14 Updated ENABLE Pin section in Applications Information 18 623345fc Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 23 LT6233/LT6233-10 LT6234/LT6235 Typical Applications The LT6233 is applied as a transimpedance amplifier with an I-to-V conversion gain of 10kΩ set by R1. The LT6233 is ideally suited to this application because of its low input offset voltage and current, and its low noise. This is because the 10k resistor has an inherent thermal noise of 13nV/√Hz or 1.3pA/√Hz at room temperature, while the LT6233 contributes only 2nV and 0.8pA/√Hz. So, with respect to both voltage and current noises, the LT6233 is actually quieter than the gain resistor. The circuit uses an avalanche photodiode with the cathode biased to approximately 200V. When light is incident on the photodiode, it induces a current IPD which flows into the amplifier circuit. The amplifier output falls negative to maintain balance at its inputs. The transfer function is therefore VOUT = –IPD • 10k. C1 ensures stability and good settling characteristics. Output offset was measured at better than 500µV, so low in part because R2 serves to cancel the DC effects of bias current. Output noise was measured at below 1mVP-P on a 20MHz measurement bandwidth, with C2 shunting R2’s thermal noise. As shown in the scope photo, the rise time is 45ns, indicating a signal bandwidth of 7.8MHz. Low Power Avalanche Photodiode Transimpedance Amplifier IS = 1.2mA ≈ 200V BIAS C1 2.7pF WWW.ADVANCEDPHOTONIX.COM 50mV/DIV ADVANCED PHOTONIX 012-70-62-541 R1 10k 5V – R2 10k Photodiode Amplifier Time Domain Response LT6233 + –5V 100ns/DIV 623345 TA02b ENABLE 623345 TA02a C2 0.1µF OUTPUT OFFSET = 500µV TYPICAL BANDWIDTH = 7.8MHz OUTPUT NOISE = 1mVP-P (20MHz MEASUREMENT BW) Related Parts PART NUMBER DESCRIPTION COMMENTS LT1028 Single, Ultralow Noise 50MHz Op Amp 0.85nV/√Hz LT1677 Single, Low Noise Rail-to-Rail Amplifier 3V Operation, 2.5mA, 4.5nV/√Hz, 60µV Max VOS LT1806/LT1807 Single/Dual, Low Noise 325MHz Rail-to-Rail Amplifier 2.5V Operation, 550µV Max VOS, 3.5nV/√Hz LT6200/LT6201 Single/Dual, Low Noise 165MHz 0.95nV√Hz, Rail-to-Rail Input and Output LT6202/LT6203/LT6204 Single/Dual/Quad, Low Noise, Rail-to-Rail Amplifier 1.9nV/√Hz, 3mA Max, 100MHz Gain Bandwidth 623345fc 24 Linear Technology Corporation LT 0111 REV C • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2003