LT6233/LT6233-10/ LT6234/LT6235 60MHz, Rail-to-Rail Output, 1.9nV/√Hz, 1.15mA Op Amp Family U DESCRIPTIO FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Low Noise Voltage: 1.9nV/√Hz Low Supply Current: 1.15mA/Amp Max Low Offset Voltage: 350µV Max Gain Bandwidth Product: LT6233: 60MHz; AV ≥ 1 LT6233-10: 375MHz; AV ≥ 10 Wide Supply Range: 3V to 12.6V Output Swings Rail-to-Rail Common Mode Rejection Ratio 115dB Typ Output Current: 30mA Operating Temperature Range – 40°C to 85°C LT6233 Shutdown to 10µA Maximum LT6233/LT6233-10 in SOT-23 Package Dual LT6234 in Tiny DFN Package U APPLICATIO S ■ ■ ■ ■ ■ Ultrasound Amplifiers Low Noise, Low Power Signal Processing Active Filters Driving A/D Converters Rail-to-Rail Buffer Amplifiers , LTC and LT are registered trademarks of Linear Technology Corporation. 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 1.15mA of supply current per amplifier. These amplifiers combine very low noise and supply current with a 60MHz gain bandwidth 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. 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 is 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. U TYPICAL APPLICATIO Noise Voltage and Unbalanced Noise Current vs Frequency Low Noise Low Power Instrumentation Amplifier VS+ 6 R6 499Ω VS+ R2 475Ω + R1 49.9Ω LT6233 – R3 475Ω R5 499Ω VOUT EN R7 VS– 499Ω VS– 5 4 4 3 3 NOISE VOLTAGE 2 1 1/2 LT6234 IN– NOISE VOLTAGE (nV/√Hz) 1/2 LT6234 6 VS = ±2.5V TA = 25°C VCM = 0V 5 AV = 20 BW = 2.8MHz VS = ±1.5V to ±5V IS = 3mA EN = 8µVRMS INPUT REFERRED, MEASUREMENT BW = 4MHz 623345 TA01a 2 1 NOISE CURRENT 0 10 100 1k 10k FREQUENCY (Hz) UNBALANCED NOISE CURRENT (pA/√Hz) R4 499Ω IN+ 0 100k 623345 TA01b 623345f 1 LT6233/LT6233-10/ LT6234/LT6235 U W W W ABSOLUTE AXI U RATI GS (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 U W U PACKAGE/ORDER I FOR ATIO ORDER PART NUMBER – V 2 5 ENABLE +IN 3 4 –IN S6 PACKAGE 6-LEAD PLASTIC SOT-23 TJMAX = 150°C, θJA = 250°C/W S6 PART MARKING* LTAFL LTAFM ORDER PART NUMBER TOP VIEW OUT A 1 –IN A 2 +IN A 3 V– 4 – + – + 8 V+ 7 OUT B 6 –IN B 5 +IN B S8 PACKAGE 8-LEAD PLASTIC SO TJMAX = 150°C, θJA = 190°C/W LT6234CS8 LT6234IS8 OUT A 1 –IN A 2 +IN A 3 V– 4 6234 6234I – + 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 + 16 – + A –IN B 6 OUT B 7 NC 8 OUT D 15 –IN D 14 +IN D D 4 +IN B 5 S8 PART MARKING – + 8 – 6 V+ OUT 1 LT6233CS6 LT6233IS6 LT6233CS6-10 LT6233IS6-10 TOP VIEW + TOP VIEW ORDER PART NUMBER 13 V + –B + C– – LT6234CDD LT6234IDD DD PART MARKING* LAET ORDER PART NUMBER LT6235CGN LT6235IGN 12 +IN C 11 –IN C 10 OUT C 9 GN PART MARKING NC GN PACKAGE 16-LEAD NARROW PLASTIC SSOP TJMAX = 150°C, θJA = 135°C/W 6235 6235I *The temperature grade is identified by a label on the shipping container.Consult LTC Marketing for parts specified with wider operating temperature ranges. 623345f 2 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 VOS Input Offset Voltage LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD MIN Input Offset Voltage Match (Channel-to-Channel) (Note 6) IB IOS TYP MAX UNITS 100 50 75 500 350 450 µV µV µV 80 450 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 Noise Voltage 0.1Hz to 10Hz 220 en Input Noise Voltage Density f = 10kHz, VS = 5V 1.9 in Input Noise Current Density, Balanced Source 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 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 RL = 1k to VS/2 53 11 100 20 V/mV V/mV nV/√Hz pA/√Hz pA/√Hz VCM Input Voltage Range Guaranteed by CMRR, VS = 5V, 0V 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 90 115 dB PSRR 1.5 1.15 nVP-P 3 4 2.65 V V Power Supply Rejection Ratio VS = 3V to 10V 90 115 dB PSRR Match (Channel-to-Channel) (Note 6) VS = 3V to 10V 95 115 dB Minimum Supply Voltage (Note 7) 3 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 ±40 ±35 ±55 ±50 1.05 0.2 mA mA 1.15 10 mA µA 623345f 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 IENABLE ENABLE Pin Current ENABLE = 0.3V VL ENABLE Pin Input Voltage LOW VH MIN TYP MAX UNITS –25 –75 µA 0.3 V V+ – 0.35 ENABLE Pin Input Voltage HIGH V µA Output Leakage Current ENABLE = V+ – 0.35V, V 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, AV = –1, RL = 1k, VO = 0.5V to 4.5V 15 V/µs 80 V/µs 1.6 MHz O = 1.5V to 3.5V 0.2 10 LT6233-10, VS = 5V, AV = –10, RL = 1k, VO = 0.5V to 4.5V 1.06 10 FPBW Full Power Bandwidth VS = 5V, VOUT = 3VP-P (Note 9) LT6233-10, HD2 = HD3 ≤ 1% 2.2 MHz tS Settling Time (LT6233, LT6234, LT6235) 0.1%, VS = 5V, VSTEP = 2V, AV = –1, RL = 1k 175 ns The ● denotes the specifications which apply over 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 LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD Input Offset Voltage Match (Channel-to-Channel) (Note 6) MAX UNITS ● ● ● MIN TYP 600 450 550 µV µV µV ● 500 µV VOS TC Input Offset Voltage Drift (Note 10) 3.0 µV/°C IB Input Bias Current ● 3.5 µA VCM = Half Supply 0.5 ● IB Match (Channel-to-Channel) (Note 6) ● 0.4 µA IOS Input Offset Current ● 0.4 µA AVOL Large-Signal Gain VS = 5V, VO = 0.5V to 4.5V, RL = 10k to VS /2 RL = 1k to VS /2 ● ● 47 12 V/mV V/mV VS = 3.3V, VO = 0.65V to 2.65V, RL = 10k to VS /2 RL = 1k to VS /2 ● ● 40 7.5 V/mV V/mV VCM Input Voltage Range Guaranteed by CMRR, VS = 5V, 0V VS = 3.3V, 0V ● ● 1.5 1.15 CMRR Common Mode Rejection Ratio VS = 5V, VCM = 1.5V to 4V VS = 3.3V, VCM = 1.15V to 2.65V ● ● 90 85 dB dB CMRR Match (Channel-to-Channel) (Note 6) VS = 5V, VCM = 1.5V to 4V ● 90 dB Power Supply Rejection Ratio VS = 3V to 10V ● 90 dB PSRR Match (Channel-to-Channel) (Note 6) VS = 3V to 10V ● 95 dB ● 3 V PSRR Minimum Supply Voltage (Note 7) VOL Output Voltage Swing LOW (Note 8) No Load ISINK = 5mA VS = 5V, ISINK = 15mA VS = 3.3V, ISINK = 10mA ● ● ● ● 4 2.65 50 195 360 265 V V mV mV mV mV 623345f 4 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over 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 VOH Output Voltage Swing HIGH (Note 8) No Load ISOURCE = 5mA VS = 5V, ISOURCE = 15mA VS = 3.3V, ISOURCE = 10mA ● ● ● ● ISC Short-Circuit Current VS = 5V VS = 3.3V ● ● IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = V+ – 0.25V ● ● IENABLE ENABLE Pin Current ENABLE = 0.3V VL ENABLE Pin Input Voltage LOW VH ENABLE Pin Input Voltage HIGH Output Leakage Current MIN TYP MAX UNITS 60 205 435 330 mV mV mV mV ±35 ±30 mA mA 1.39 mA µA ● –85 µA ● 0.3 V ● 1 V+ – 0.25 V ENABLE = V+ – 0.25V, VO = 1.5V to 3.5V ● 1 µA 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 ● 120 µs SR Slew Rate 75 V/µs FPBW Full Power Bandwidth (Note 9) VS = 5V, AV = –1, RL = 1k, VO = 0.5V to 4.5V ● LT6233-10, AV = –10, RL = 1k, VO = 0.5V to 4.5V ● LT6233, VS = 5V, VOUT = 3VP-P ● 9 V/µs 955 kHz The ● denotes the specifications which apply over – 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 VOS Input Offset Voltage LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD Input Offset Voltage Match (Channel-to-Channel) (Note 6) VOS TC Input Offset Voltage Drift (Note 10) IB Input Bias Current IB Match (Channel-to-Channel) (Note 6) IOS Input Offset Current AVOL Large-Signal Gain VCM = Half Supply MAX UNITS ● ● ● MIN 700 550 650 µV µV µV ● 550 µV 3 µV/°C ● 4 µA ● 0.4 µA 0.5 ● 0.5 ● VS = 5V, VO = 0.5V to 4.5V, RL = 10k to VS /2 RL = 1k to VS /2 TYP µA ● ● 45 11 V/mV V/mV VS = 3.3V, VO = 0.65V to 2.65V,RL = 10k to VS /2 ● RL = 1k to VS /2 ● 38 7 V/mV V/mV VCM Input Voltage Range Guaranteed by CMRR, VS = 5V, 0V VS = 3.3V, 0V ● ● 1.5 1.15 CMRR Common Mode Rejection Ratio VS = 5V, VCM = 1.5V to 4V VS = 3.3V, VCM = 1.15V to 2.65V ● ● 90 85 dB dB CMRR Match (Channel-to-Channel) (Note 6) VS = 5V, VCM = 1.5V to 4V ● 90 dB Power Supply Rejection Ratio VS = 3V to 10V ● 90 dB PSRR 4 2.65 V V 623345f 5 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over – 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 PSRR Match (Channel-to-Channel) (Note 6) VS = 3V to 10V Minimum Supply Voltage (Note 7) MIN TYP MAX UNITS ● 95 dB ● 3 V VOL Output Voltage Swing LOW (Note 8) No Load ISINK = 5mA VS = 5V, ISINK = 15mA VS = 3.3V, ISINK = 10mA ● ● ● ● 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 ● ● ● ● 60 210 445 335 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+ – 0.2V ● ● IENABLE ENABLE Pin Current ENABLE = 0.3V VL ENABLE Pin Input Voltage LOW VH ENABLE Pin Input Voltage HIGH Output Leakage Current ±30 ±20 mA mA 1.46 mA µA ● –100 µA ● 0.3 V ● 1 V+ – 0.2V V ENABLE = V+ – 0.2V, VO = 1.5V to 3.5V ● 1 µA 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 ● 135 µs SR Slew Rate 70 V/µs FPBW Full Power Bandwidth (Note 9) VS = 5V, AV = –1, RL = 1k, VO = 0.5V to 4.5V ● LT6233-10, AV = –10, RL = 1k, VO = 0.5V to 4.5V ● LT6233, VS = 5V, VOUT = 3VP-P ● 8 V/µs 848 kHz 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 Input Offset Voltage Match (Channel-to-Channel) (Note 6) IB IOS MIN TYP MAX UNITS 100 50 75 500 350 450 µV µV µV 100 450 µV Input Bias Current 1.5 3 µA IB Match (Channel-to-Channel) (Note 6) 0.04 0.3 µA 0.04 0.3 Input Offset Current Input Noise Voltage 0.1Hz to 10Hz 220 en Input Noise Voltage Density f = 10kHz 1.9 in Input Noise Current Density, Balanced Source Unbalanced Source f = 10kHz, RS = 10k f = 10kHz, RS = 10k 0.43 0.78 µA nVP-P 3.0 nV/√Hz pA/√Hz pA/√Hz 623345f 6 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS TA = 25°C, VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS 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 RL = 1k 97 28 180 55 V/mV V/mV VCM Input Voltage Range Guaranteed by CMRR –3 CMRR PSRR MIN TYP MAX 4 UNITS V Common Mode Rejection Ratio VCM = –3V to 4V 90 110 dB CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V 95 120 dB Power Supply Rejection Ratio VS = ±1.5V to ±5V 90 115 dB 95 115 PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V 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 ENABLE = 4.65V 1.15 0.2 1.25 10 mA µA IENABLE ENABLE Pin Current ENABLE = 0.3V –35 –85 µA VL ENABLE Pin Input Voltage LOW 0.3 V VH ENABLE Pin Input Voltage HIGH ±40 dB ±55 mA 4.65 V Output Leakage Current ENABLE = 4.65V, VO = ±1V 0.2 tON Turn-On Time ENABLE = 5V to 0V, RL = 1k 900 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 115 V/µs 1.8 MHz LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V 1.27 10 µA FPBW Full Power Bandwidth VOUT = 3VP-P (Note 9) LT6233-10, HD2 = HD3 ≤ 1% 2.2 MHz tS Settling Time (LT6233, LT6234, LT6235) 0.1%, VSTEP = 2V, AV = –1, RL = 1k 170 ns 623345f 7 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over 0°C < TA < 70°C temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD MAX UNITS ● ● ● MIN TYP 600 450 550 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) ● 500 µV VOS TC Input Offset Voltage Drift (Note 10) ● IB Input Bias Current ● 3.5 µA IB Match (Channel-to-Channel) (Note 6) ● 0.4 µA 0.5 3 0.4 µV/°C µA IOS Input Offset Current AVOL Large-Signal Gain VO = ±4.5V,RL = 10k RL = 1k ● ● 75 22 VCM Input Voltage Range Guaranteed by CMRR ● –3 CMRR Common Mode Rejection Ratio VCM = –3V to 4V ● 90 dB CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V ● 95 dB ● V/mV V/mV 4 V Power Supply Rejection Ratio VS = ±1.5V to ±5V ● 90 dB PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V ● 95 dB VOL Output Voltage Swing LOW (Note 8) No Load ISINK = 5mA ISINK = 15mA ● ● ● 50 195 360 mV mV mV VOH Output Voltage Swing HIGH (Note 8) No Load ISOURCE = 5mA ISOURCE = 15mA ● ● ● 60 205 435 mV mV mV ISC Short-Circuit Current IS Supply Current per Amplifier Disabled Supply Current per Amplifier ENABLE = 4.75V ● ● IENABLE ENABLE Pin Current ENABLE = 0.3V VL ENABLE Pin Input Voltage LOW VH ENABLE Pin Input Voltage HIGH PSRR Output Leakage Current ● ±35 mA 1.53 mA µA ● –95 µA ● 0.3 V ● 1 4.75 V ENABLE = 4.75V, VO = ±1V ● 1 µA ns tON Turn-On Time ENABLE = 5V to 0V, RL = 1k ● 900 tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k ● 150 SR Slew Rate AV = –1, RL = 1k, VO = –2V to 2V ● LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V ● LT6233, VOUT = 3VP-P ● FPBW Full Power Bandwidth (Note 9) 11 105 1.16 µs V/µs V/µs MHz 623345f 8 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over –40°C < TA < 85°C temperature range. VS = ±5V, VCM = VOUT = 0V, ENABLE = 0V, unless otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS VOS Input Offset Voltage LT6233S6, LT6233S6-10 LT6234S8, LT6235GN LT6234DD MAX UNITS ● ● ● MIN TYP 700 550 650 µV µV µV Input Offset Voltage Match (Channel-to-Channel) (Note 6) ● 550 µV VOS TC Input Offset Voltage Drift (Note 10) ● 3 µV/°C IB Input Bias Current ● 4 µA IB Match (Channel-to-Channel) (Note 6) ● 0.4 µA 0.5 0.5 µA IOS Input Offset Current AVOL Large-Signal Gain VO = ±4.5V,RL = 10k RL = 1k ● ● 68 20 VCM Input Voltage Range Guaranteed by CMRR ● –3 CMRR Common Mode Rejection Ratio VCM = –3V to 4V ● 90 dB CMRR Match (Channel-to-Channel) (Note 6) VCM = –3V to 4V ● 90 dB ● V/mV V/mV 4 V Power Supply Rejection Ratio VS = ±1.5V to ±5V ● 90 dB PSRR Match (Channel-to-Channel) (Note 6) VS = ±1.5V to ±5V ● 95 dB VOL Output Voltage Swing LOW (Note 8) No Load ISINK = 5mA ISINK = 15mA ● ● ● 50 195 370 mV mV mV VOH Output Voltage Swing HIGH (Note 8) No Load ISOURCE = 5mA ISOURCE = 15mA ● ● ● 70 210 445 mV mV mV ISC Short-Circuit Current ● IS Supply Current per Amplifier Disabled Supply Current per Amplifier 1.61 ENABLE = 4.8V ● ● mA µA IENABLE ENABLE Pin Current ENABLE = 0.3V ● –110 µA VL ENABLE Pin Input Voltage LOW ● VH ENABLE Pin Input Voltage HIGH ● PSRR Output Leakage Current ±30 mA 1 0.3 4.8 V V ENABLE = 4.8V, VO = ±1V ● 1 µA tON Turn-On Time ENABLE = 5V to 0V, RL = 1k ● 900 ns tOFF Turn-Off Time ENABLE = 0V to 5V, RL = 1k ● 160 µs SR Slew Rate 95 V/µs FPBW Full Power Bandwidth (Note 9) AV = –1, RL = 1k, VO = –2V to 2V ● LT6233-10, AV = –10, RL = 1k, VO = –2V to 2V ● LT6233, VOUT = 3VP-P ● 10 1.06 V/µs MHz 623345f 9 LT6233/LT6233-10/ LT6234/LT6235 ELECTRICAL CHARACTERISTICS Note 1: Absolute maximum ratings are those values beyond which the life of the device may be impaired. 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 and 85°C. 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. 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. U W TYPICAL PERFOR A CE 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 VS = 5V, 0V 400 40 30 20 300 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 0 2 10 12 8 6 TOTAL SUPPLY VOLTAGE (V) 4 623345 GO1 3 TA = –55°C 2 TA = 125°C TA = 25°C 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 0 –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 1 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 Input Bias Current vs Common Mode Voltage 6 –500 14 –1 –50 –25 0 50 75 25 TEMPERATURE (°C) 100 125 623345 GO5 VS = 5V, 0V 1 0.1 TA = 125°C TA = –55°C 0.01 TA = 25°C 0.001 0.0001 0.01 1 10 0.1 LOAD CURRENT (mA) 100 623345 GO6 623345f 10 LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE 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 0.4 0.2 0 –0.2 TA = –55°C –0.4 –0.6 TA = 25°C 0.001 0.01 TA = 25°C –0.8 0.1 1 10 LOAD CURRENT (mA) –1.0 100 TA = 125°C 2.5 VS = 3V, 0V TA = 25°C –20 RL = 100Ω –1.0 TA = 25°C 1.0 0.5 RL = 1k 0 RL = 100Ω –0.5 –1.0 0.5 –2.5 –0.5 623345 G10 40 CHANGE IN OFFSET VOLTAGE (µV) 1.0 0.5 0 –0.5 –1.0 TA = –55°C –1.5 –2.0 –90 100 TA = 25°C 35 VS = ±5V 30 25 VS = ±2.5V 20 15 5 Total Noise vs Total Source Resistance TOTAL NOISE (nV/√Hz) VS = ±5V TA = 125°C 4 623345 G12 Warm-Up Drift vs Time 1.5 –5 –4 –3 –2 –1 0 1 2 3 OUTPUT VOLTAGE (V) 623345 G11 Offset Voltage vs Output Current 2.0 RL = 100Ω –1.0 –2.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 OUTPUT VOLTAGE (V) RL = 1k 0 –2.0 3.0 VS = ±5V TA = 25°C 1.0 –1.5 2.5 5.0 2.5 1.5 –2.0 1.0 1.5 2.0 OUTPUT VOLTAGE (V) 3.0 3.5 4.0 4.5 POWER SUPPLY VOLTAGE (±V) 2.0 2.0 –1.5 0.5 TA = –55°C –60 –2.0 0 TA = 125°C –40 –1.5 –2.5 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 2.0 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 TA = 25°C –60 –30 0 30 60 90 OUTPUT CURRENT (mA) 623345 G13 0 0.1 0 10 30 40 20 TIME AFTER POWER-UP (s) 50 623345 G14 10 100 1k 10k TOTAL SOURCE RESISTANCE (Ω) 100k 623345 G15 623345f 11 LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE CHARACTERISTICS (LT6233/LT6234/LT6235) 0.1Hz to 10Hz Output Voltage Noise Noise Voltage and Unbalanced Noise Current vs Frequency 3 3 NOISE VOLTAGE 2 1 1 NOISE CURRENT 0 100 10 100nV –100nV 0 100k 1k 10k FREQUENCY (Hz) 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 40 –80 30 22 GAIN BANDWIDTH AV = 1 1 1M 10M FREQUENCY (Hz) 100M 623345 G22 125 VS = ±5V FALLING 18 16 VS = ±2.5V FALLING 14 VS = ±2.5V RISING 12 2 0 10 12 8 6 TOTAL SUPPLY VOLTAGE (V) 4 10 –55 –35 –15 14 5 25 45 65 85 105 125 TEMPERATURE (°C) 623345 G21 Channel Separation vs Frequency –40 100 CHANNEL SEPARATION (dB) AV = 2 95 20 Common Mode Rejection Ratio vs Frequency AV = 10 VS = ±5V RISING 623345 G20 COMMON MODE REJECTION RATIO (dB) OUTPUT IMPEDANCE (Ω) 60 40 50 –60 VS = 5V, 0V 0.1 100k 65 35 5 TEMPERATURE (°C) 26 120 10 –25 AV = –1 24 RF = RG = 1k 60 Output Impedance vs Frequency 100 VS = 3V, 0V 70 50 70 623345 G19 1k GAIN BANDWIDTH Slew Rate vs Temperature PHASE MARGIN (DEG) 50 VS = ±5V 60 623345 G18 80 TA = 25°C CL = 5pF RL = 1k GAIN BANDWIDTH (MHz) PHASE 60 40 CL = 5pF 80 RL = 1k VCM = VS/2 70 Gain Bandwidth and Phase Margin vs Supply Voltage 120 CL = 5pF RL = 1k 100 VCM = VS/2 80 70 PHASE MARGIN 623345 G17 Open Loop Gain vs Frequency 80 90 40 –55 5s/DIV 60 50 VS = 3V, 0V 50 SLEW RATE (V/µs) 2 VS = ±5V GAIN BANDWIDTH (MHz) 4 100nV/DIV 4 70 VS = ±2.5V 80 60 40 20 VS = 5V, 0V VCM = VS/2 0 10k 100k AV = 1 –50 TA = 25°C VS = ±5V –60 –70 –80 –90 –100 –110 –120 –130 1M 10M FREQUENCY (Hz) 100M 1G 623345 G23 –140 100k 1M 10M FREQUENCY (Hz) 100M 623345 G24 623345f 12 PHASE MARGIN (DEG) 5 6 VS = ±2.5V TA = 25°C VCM = 0V 5 UNBALANCED NOISE CURRENT (pA/√Hz) NOISE VOLTAGE (nV/√Hz) 6 Gain Bandwidth and Phase Margin vs Temperature LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE CHARACTERISTICS (LT6233/LT6234/LT6235) Power Supply Rejection Ratio vs Frequency 80 VS = 5V, 0V 45 AV = 2 RS = 10Ω 40 POSITIVE SUPPLY 60 40 50 VS = 5V, 0V 45 AV = 1 NEGATIVE SUPPLY 20 0 35 RS = 20Ω 30 25 20 RS = 50Ω RL = 50Ω 15 10M 5 0 100 CAPACITIVE LOAD (pF) 10 100M 1000 400 350 500Ω SETTLING TIME (ns) SETTLING TIME (ns) – VOUT + VIN 250 500Ω 200 1mV 10mV 150 1mV 10mV 100 – VIN 300 Maximum Undistorted Output Signal vs Frequency VS = ±5V TA = 25°C AV = –1 500Ω VOUT + 250 200 1mV 1mV 10mV 150 10mV 100 –4 –3 –2 –1 1 2 0 OUTPUT STEP (V) 3 50 4 –4 –3 –2 –1 1 2 0 OUTPUT STEP (V) 623345 G28 –80 RL = 1k, 2ND 6 5 4 V = ±5V 3 T S = 25°C A HD2, HD3 < –40dBc 2 100k 1M 10k FREQUENCY (Hz) 10M 623345 G31 10M Distortion vs Frequency –70 VS = ±2.5V A =2 –40 VV = 2V (P–P) OUT RL = 100Ω, 2ND –60 RL = 100Ω, 3RD RL = 1k, 3RD –80 –90 –90 100k 1M FREQUENCY (Hz) DISTORTION (dBc) RL = 100Ω, 3RD –100 10k 7 –30 VS = ±5V AV = 1 –50 VOUT = 2V(P–P) RL = 1k, 3RD AV = –1 8 623345 G30 –40 VS = ±2.5V AV = 1 –50 VOUT = 2V(P–P) RL = 100Ω, 2ND 4 AV = 2 9 Distortion vs Frequency Distortion vs Frequency –60 3 10 623345 G29 –40 –100 10k 1000 623345 G27 Settling Time vs Output Step (Inverting) VS = ±5V TA = 25°C 350 AV = 1 300 100 CAPACITIVE LOAD (pF) 10 623345 G26 400 DISTORTION (dBc) 15 OUTPUT VOLTAGE SWING (VP–P) 1M 100k FREQUENCY (Hz) RS = 50Ω RL = 50Ω 20 10 Settling Time vs Output Step (Non-Inverting) –70 25 5 DISTORTION (dBc) 10k RS = 20Ω 30 10 623345 G25 50 35 0 1k 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 RL = 100Ω, 2ND –50 –60 RL = 1k, 3RD RL = 100Ω, 3RD –70 –80 RL = 1k, 2ND RL = 1k, 2ND –90 100k 1M FREQUENCY (Hz) 10M 623345 G32 –100 10k 100k 1M FREQUENCY (Hz) 10M 623345 G33 623345f 13 LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE CHARACTERISTICS (LT6233/LT6234/LT6235) Large Signal Response Distortion vs Frequency Small Signal Response –30 RL = 100Ω, 2ND –60 2V RL = 1k, 3RD RL = 100Ω, 3RD –70 50mV/DIV –50 1V/DIV DISTORTION (dBc) VS = ±5V AV = 2 –40 V OUT = 2V(P–P) 0V 0V –2V –80 RL = 1k, 2ND VS = ±2.5V AV = –1 RL = 1k –90 –100 10k 100k 1M FREQUENCY (Hz) VS = ±2.5V AV = 1 RL = 1k 200ns/DIV 623345 G35 200ns/DIV 623345 G36 10M 623345 G34 Large Signal Response Output Overdrive Recovery –5V VS = ±5V AV = 1 RL = 1k VIN (1V/DIV) 0V 0V VOUT (2V/DIV) 2V/DIV 5V 0V VS = ±2.5V AV = 3 200ns/DIV 200ns/DIV 623345 G37 623345 G38 (LT6233) ENABLE Characteristics Supply Current vs ENABLE Pin Voltage ENABLE Pin Current vs ENABLE Pin Voltage 35 TA = 125°C TA = –55°C 30 1.0 TA = –55°C 0.8 0.6 0.4 0.2 0 25 VS = ±2.5V AV = 1 TA = 25°C –2.0 0 1.0 –1.0 PIN VOLTAGE (V) 2.0 623345 G39 0V 20 TA = 125°C 15 0.5V 10 5 VS = ±2.5V 5V VOUT TA = 25°C ENABLE PIN CURRENT (µA) SUPPLY CURRENT (mA) 1.2 ENABLE Pin Response Time ENABLE PIN 1.4 0 –2.0 0 1.0 –1.0 PIN VOLTAGE (V) 2.0 0V VS = ±2.5V VIN = 0.5V AV = 1 RL = 1k 200µs/DIV 623345 G41 623345 G40 623345f 14 LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE CHARACTERISTICS (LT6233-10) Gain Bandwidth and Phase Margin vs Temperature 200 VS = ±5V GAIN BANDWIDTH 300 VS = 3V, 0V 250 200 VS = ±5V 70 PHASE MARGIN VS = 3V, 0V –50 75 50 25 TEMPERATURE (°C) –25 0 100 70 100 VS = ±2.5V RISING 60 60 40 50 20 40 125 20 0 VS = 3V, 0V 40 30 20 VS = 3V, 0V 20 0 10 –20 VS = ±5V 0 –40 –10 TA = 25°C AV = 10 375 CL = 5pF RL = 1k 300 GAIN BANDWIDTH 225 100 PHASE MARGIN 50 –60 –20 100k –80 1M 10M 100M FREQUENCY (Hz) 1G 0 2 4 8 10 6 TOTAL SUPPLY VOLTAGE (V) 623345 G45 60 40 20 0 10k 100k 1M 10M FREQUENCY (Hz) 100M 1G 623345 G48 200 150 100 50 0 0 0 1000 400 800 600 TOTAL RESISTOR LOAD (Ω) (INCLUDES FEEDBACK R) 623345 G47 200 2nd and 3rd Harmonic Distortion vs Frequency –30 VS = ±2.5V A = 10 –40 VV = 2V (P–P) OUT 10 9 OUTPUT VOLTAGE SWING (VP–P) COMMON MODE REJECTION RATIO (dB) 80 250 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 = 100 350 8 DISTORTION (dBc) GAIN (dB) 60 PHASE (DEG) GAIN 40 Gain Bandwidth vs Resistor Load 400 450 AV = 10 CL = 5pF 100 RL = 1k VCM = VS/2 80 7 6 5 4 3 2 VS = ±5V TA = 25°C 1 AV = 10 HD2, HD3 ≤ 40dBc 0 100k 1M 10k FREQUENCY (Hz) 10000 623345 G44 PHASE MARGIN (DEG) VS = ±5V 50 100 1000 CAPACITIVE LOAD (pF) 10 5 25 45 65 85 105 125 TEMPERATURE (°C) Gain Bandwidth and Phase Margin vs Supply Voltage GAIN BANDWIDTH (MHz) 60 RS = 50Ω 623345 G43 120 PHASE 30 10 0 –55 –35 –15 Open Loop Gain vs Frequency 70 RS = 20Ω 40 VS = ±2.5V FALLING 623345 G42 80 RS = 10Ω 50 120 80 VS = 5V, 0V AV = 10 60 VS = ±5V FALLING GAIN BANDWIDTH (MHz) 350 PHASE MARGIN (DEG) GAIN BANDWIDTH (MHz) 400 AV = –10 180 RF = 1k RG = 100Ω 160 VS = ±5V RISING 140 OVERSHOOT (%) AV = 10 SLEW RATE (V/µs) 450 Series Output Resistance and Overshoot vs Capacitive Load Slew Rate vs Temperature –50 RL = 100Ω, 3RD –60 RL = 1k, 3RD RL = 100Ω, 2ND RL = 1k, 2ND –70 –80 –90 10M –100 10k 100k 1M FREQUENCY (Hz) 10M 623345 G50 623345 G49 623345f 15 LT6233/LT6233-10/ LT6234/LT6235 U W TYPICAL PERFOR A CE CHARACTERISTICS (LT6233-10) 2nd and 3rd Harmonic Distortion vs Frequency Large Signal Response Output-Overload Recovery –30 RL = 100Ω, 3RD RL = 100Ω, 2ND –60 0V 0V 0V RL = 1k, 3RD –70 –80 –90 –100 10k VOUT (2V/DIV) RL = 1k, 2ND VIN (0.5V/DIV) –50 VOUT (2V/DIV) DISTORTION (dBc) VS = ±5V A = 10 –40 VV = 2V (P–P) OUT VS = ±5V 100ns/DIV AV = 10 RF = 900Ω, RG = 100Ω 100k 1M FREQUENCY (Hz) VS = 5V, 0V 100ns/DIV AV = 10 RF = 900Ω, RG = 100Ω 623345 G52 623345 G53 10M 623345 G51 Input Referred High Frequency Noise Spectrum Small Signal Response 1nV/√Hz/DIV VOUT (100mV/DIV) 10 2.5V 0 VS = 5V, 0V 100ns/DIV AV = 10 RF = 900Ω, RG = 100Ω 100kHz 20MHz 2MHz/DIV 623345 G54 623345 G55 623345f 16 LT6233/LT6233-10/ LT6234/LT6235 U U W U APPLICATIO S I FOR ATIO Amplifier Characteristics 2.5V 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. +V Q5 CM Q3 –V +V DESD1 +V Q4 DESD5 VOUT C1 DESD2 –V Q1 –VIN D1 DESD6 DIFFERENTIAL DRIVE GENERATOR –V Q2 Q6 D2 +V +VIN DESD3 I1 DESD4 –V BIAS ENABLE +V –V 623345 F01 Figure 1. Simplified Schematic 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 over voltage 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 1V/DIV 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. 0V –2.5V 500µs/DIV 623345 F02 Figure 2. VS = ±2.5V, AV = 1 with Large Overdrive 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. 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. 623345f 17 LT6233/LT6233-10/ LT6234/LT6235 U W U U APPLICATIO S I FOR ATIO 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 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 Characteristic Curves. 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. 623345f 18 LT6233/LT6233-10/ LT6234/LT6235 U U W U APPLICATIO S I FOR ATIO Single Supply, Low Noise, Low Power, Bandpass Filter with Gain = 10 Frequency Response Plot of Bandpass Filter 23 R1 732Ω C2 47pF f0 = V+ 1 = 1MHz 2πRC R2 732Ω ( 0.1µF R3 10k – VIN LT6233 + C3 0.1µF R4 10k VOUT EN GAIN (dB) C = √C1C2, R = R1 = R2 C1 1000pF ) 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 3 –7 100k 623345 F03 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 R15 88.7Ω EN C1 1µF V+ R10 511Ω R13 2k – R6 511Ω U3 LT6233 + R3 30.9Ω R5 511Ω R4 V+ 511Ω C3 1µF R12 511Ω R14 2k – U2 LT6233-10 + VIN2 R16 88.7Ω EN C9 68pF 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 623345f 19 LT6233/LT6233-10/ LT6234/LT6235 U PACKAGE DESCRIPTIO 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) 1.90 BSC S6 TSOT-23 0302 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 623345f 20 LT6233/LT6233-10/ LT6234/LT6235 U PACKAGE DESCRIPTIO DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698) R = 0.115 TYP 5 0.38 ± 0.10 8 0.675 ±0.05 3.5 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 3.00 ±0.10 (4 SIDES) PACKAGE OUTLINE 1.65 ± 0.10 (2 SIDES) PIN 1 TOP MARK (DD8) DFN 0203 0.28 ± 0.05 0.200 REF 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 0.75 ±0.05 0.00 – 0.05 4 0.28 ± 0.05 1 0.50 BSC 2.38 ±0.10 (2 SIDES) BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1) 2. ALL DIMENSIONS ARE IN MILLIMETERS 3. 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 4. EXPOSED PAD SHALL BE SOLDER PLATED 623345f 21 LT6233/LT6233-10/ LT6234/LT6235 U PACKAGE DESCRIPTIO 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 8 .245 MIN 7 6 5 .160 ±.005 .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) .008 – .010 (0.203 – 0.254) 0°– 8° TYP .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN .053 – .069 (1.346 – 1.752) .014 – .019 (0.355 – 0.483) TYP 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) 2 3 4 .004 – .010 (0.101 – 0.254) .050 (1.270) BSC SO8 0303 623345f 22 LT6233/LT6233-10/ LT6234/LT6235 U PACKAGE DESCRIPTIO 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 TYP RECOMMENDED SOLDER PAD LAYOUT 1 .015 ± .004 × 45° (0.38 ± 0.10) .007 – .0098 (0.178 – 0.249) 2 3 4 5 6 7 .053 – .068 (1.351 – 1.727) 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) .008 – .012 (0.203 – 0.305) .0250 (0.635) BSC 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 GN16 (SSOP) 0502 623345f 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 U TYPICAL APPLICATIO S 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 Photodiode Amplifier Time Domain Response C1 2.7pF WWW.ADVANCEDPHOTONIX.COM 50mV/DIV ADVANCED PHOTONIX 012-70-62-541 R1 10k 5V – R2 10k LT6233 + 100ns/DIV –5V ENABLE 623345 TA02b 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, Ultra Low 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 623345f 24 Linear Technology Corporation LT/TP 1003 1K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2003