NOT RE RE C COM M E OM M N E N D D ED F O ED R R NE I SL 2 E PLA C E W D ES I 8233 G M EN FU Z T P A NS RT ISL28233I Features The ISL28233IUZ is a dual micropower, zero-drift operational amplifier that is optimized for single and dual supply operation from 1.65V to 5.5V and ±0.825V to ±2.75V. The low supply current of 18µA and wide input range enable the ISL28233IUZ to be an excellent general purpose op amp for a range of applications. The ISL28233IUZ is ideal for handheld devices that operate off 2 AA or single Li-ion batteries. • Low Input Offset Voltage . . . . . . . . . . . 8µV, Max. The ISL28233IUZ is available in an industry standard pinout 8 Ld MSOP package. It operates over the temperature range of -40°C to +85°C. • Low Offset Drift . . . . . . . . . . . . . 0.06µV/°C, Max • Quiescent Current (Per Amplifier) . . . . . 18µA, Typ. • Single Supply Range . . . . . . . . . +1.65V to +5.5V • Dual Supply Range . . . . . . . . ±0.825V to ±2.75V • Low Noise (0.01Hz to 10Hz) . . . . . . . 1.1µVP-P, Typ. • Rail-to-Rail Inputs and Output • Input Bias Current . . . . . . . . . . . . . 110pA, Max. • Operating Temperature Range . . . -40°C to +85°C Applications • Bi-Directional Current Sense • Temperature Measurement • Medical Equipment • Electronic Weigh Scales • Precision/Strain Gauge Sensor • Precision Regulation • Low Ohmic Current Sense • High Gain Analog Front Ends Typical Application VOS vs TEMP V+ +1.65V TO +5.5V VREF 499k 4.99k + V+ 0.1 - VSENSE OUT V- 499k 4.99k GND I-SENSE- BI-DIRECTIONAL CURRENT SENSE AMPLIFIER November 17, 2011 FN6942.2 1 8 INPUT OFFSET VOLTAGE (µV) I-SENSE+ 6 N = 60 MAX 4 2 MEDIAN 0 -2 MIN -4 -6 -8 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas Inc. 2010, 2011. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. ISL28233I Dual Micropower, Zero-Drift, RRIO Operational Amplifiers ISL28233I Ordering Information PART NUMBER (Note 3) PART MARKING PACKAGE (Pb-Free) PKG. DWG. # ISL28233IUZ (Note 2) 8233Z 8 Ld MSOP M8.118A ISL28233IUZ-T7 (Notes 1, 2) 8233Z 8 Ld MSOP M8.118A NOTES: 1. Please refer to TB347 for details on reel specifications. 2. These Intersil Pb-free plastic packaged products employ special Pb-free material sets, molding compounds/die attach materials, and 100% matte tin plate plus anneal (e3 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations). Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 3. For Moisture Sensitivity Level (MSL), please see device information page for ISL28233I. For more information on MSL please see techbrief TB363. 2 FN6942.2 November 17, 2011 ISL28233I Pin Configurations ISL28233IUZ (8 LD MSOP) TOP VIEW OUT_A 1 IN-_A 2 8 V+ 7 OUT_B - + IN+_A 3 + - V- 4 6 IN-_B 5 IN+_B Pin Descriptions ISL28233IUZ (8 Ld MSOP) PIN NAME FUNCTION 3 IN+_A Non-inverting input 5 IN+_B EQUIVALENT CIRCUIT V+ + IN+_C - IN+ + IN+_D IN- CLOCK GEN + DRIVERS VCircuit 1 4 V- Negative supply 2 IN-_A Inverting input 6 IN-_B (See Circuit 1) IN-_C IN-_D 1 OUT_A 7 OUT_B Output V+ OUT_C OUT OUT_D V- Circuit 2 8 V+ Positive supply 3 FN6942.2 November 17, 2011 ISL28233I Absolute Maximum Ratings Max Supply Voltage V+ to V- . . . Max Voltage VIN to GND . . . . . . Max Input Differential Voltage . . Max Input Current . . . . . . . . . . Max Voltage VOUT to GND (10s) ESD Tolerance Human Body Model . . . . . . . . Machine Model . . . . . . . . . . . Charged Device Model . . . . . . Latch-Up Passed Per JESD78B . . Thermal Information .... (V- .... .... .... ........... 0.3V) to (V+ + ........... ........... ........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6.5V 0.3V)V . 6.5V . 20mA .±3.0V . 4000V . . 400V . 2000V +125°C Thermal Resistance (Typical) θJA (°C/W) θJC (°C/W) 8 Ld MSOP (Notes 4, 5) . . . . . . . . 180 65 Maximum Storage Temperature Range . . . -65°C to +150°C Pb-Free Reflow Profile . . . . . . . . . . . . . . . . . .see link below http://www.intersil.com/pbfree/Pb-FreeReflow.asp Operating Conditions Temperature Range . . . . . . . . . . . . . . . . . . -40°C to +85°C CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and result in failures not covered by warranty. NOTES: 4. θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details. 5. For θJC, the “case temp” location is taken at the package top center. Electrical Specifications PARAMETER V+ = 5V, V- = 0V, VCM = 2.5V, TA = +25°C, RL = 10kΩ, unless otherwise specified. Boldface limits apply over the operating temperature range, -40°C to +85°C. DESCRIPTION CONDITIONS MIN (Note 6) TYP MAX (Note 6) UNIT -8 ±2 8 µV -11.9 - 11.9 µV -0.06 0.02 0.06 µV/°C DC SPECIFICATIONS VOS Input Offset Voltage TCVOS Input Offset Voltage Temperature Coefficient IOS Input Offset Current - 1 - pA TCIOS Input Offset Current Temperature Coefficient - 0.11 - pA/°C IB Input Bias Current -110 ±30 110 pA -110 - 110 pA - 0.49 - pA/°C V+ = 5.0V, V- = GND -0.1 - 5.1 V VCM = -0.1V to 5.1V 118 125 - dB - dB - dB - dB 4.981 - V 18 35 mV 174 - dB 1.65 - 5.5 V - 18 25 µA - - 35 µA TCIB Input Bias Current Temperature Coefficient Common Mode Input Voltage Range CMRR Common Mode Rejection Ratio 115 PSRR Power Supply Rejection Ratio Vs = 1.65V to 5.5V 110 138 110 VOH Output Voltage Swing, High VOL Output Voltage Swing, Low AOL Open Loop Gain RL = 1MΩ V+ Supply Voltage Guaranteed by PSRR IS Supply Current, Per Amplifier RL = OPEN RL = 10kΩ 4.965 ISC+ Output Source Short Circuit Current RL = Short to ground or V+ 13 17 26 mA ISC- Output Sink Short Circuit Current -26 -19 -13 mA 4 FN6942.2 November 17, 2011 ISL28233I Electrical Specifications PARAMETER V+ = 5V, V- = 0V, VCM = 2.5V, TA = +25°C, RL = 10kΩ, unless otherwise specified. Boldface limits apply over the operating temperature range, -40°C to +85°C. (Continued) DESCRIPTION CONDITIONS MIN (Note 6) TYP MAX (Note 6) UNIT AC SPECIFICATIONS GBWP Gain Bandwidth Product f = 50kHz AV = 100, RF = 100kΩ, RG = 1kΩ, RL = 10kΩ to VCM - 400 - kHz eN VP-P Peak-to-Peak Input Noise Voltage f = 0.01Hz to 10Hz - 1.1 - µVP-P eN Input Noise Voltage Density f = 1kHz - 65 - nV/√(Hz ) iN Input Noise Current Density f = 1kHz - 72 - fA/√(Hz) f = 10Hz - 79 - fA/√(Hz) f = 1MHz - 1.6 - pF - 1.12 - pF - 0.2 - V/µs - 0.1 - V/µs AV = +1, VOUT = 0.1VP-P, RF = 0Ω, RL = 10kΩ, CL = 1.2pF - 1.1 - µs - 1.1 - µs AV = +1, VOUT = 2VP-P, RF = 0Ω, RL = 10kΩ, CL = 1.2pF - 8 - µs - 10 - µs Cin Differential Input Capacitance Common Mode Input Capacitance TRANSIENT RESPONSE SR Positive Slew Rate VOUT = 1V to 4V, RL = 10kΩ Negative Slew Rate tr, tf, Small Signal Rise Time, tr 10% to 90% Fall Time, tf 10% to 90% tr, tf Large Signal Rise Time, tr 10% to 90% Fall Time, tf 10% to 90% ts Settling Time to 0.1%, 2VP-P Step AV = +1, RF = 0Ω, RL = 10kΩ, CL = 1.2pF - 35 - µs trecover Output Overload Recovery Time, Recovery to 90% of output saturation AV = +2, RF = 10kΩ, RL = Open, CL = 3.7pF - 10.5 - µs NOTE: 6. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization and are not production tested. 5 FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves n V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. 8 2 INPUT OFFSET VOLTAGE (µV) INPUT OFFSET VOLTAGE (µV) 3 MAX 1 0 MEDIAN -1 -2 MIN -3 N = 59 -4 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 4 2 MEDIAN 0 -2 -4 VS = ±1V VIN = 0V MIN RL =OPEN -6 -8 5.5 N = 59 MAX 6 -40 -20 0 4 MEDIAN 0 -2 VS = ±2.5V VIN = 0V RL =OPEN MIN -4 -6 -8 -40 -20 0 20 40 60 TEMPERATURE (°C) 80 80 100 N = 54 80 60 VS = 5V 40 20 VS = 1.65V 0 -20 -40 -40 100 -20 0 20 40 60 TEMPERATURE (°C) 80 100 FIGURE 4. MEDIAN IB+ vs TEMPERATURE FIGURE 3. VOS vs TEMPERATURE 20 80 N = 54 N = 54 70 INPUT OFFSET CURRENT (pA) INPUT BIAS CURRENT (pA) 60 100 N = 60 MAX INPUT BIAS CURRENT (pA) INPUT OFFSET VOLTAGE (µV) 8 2 40 FIGURE 2. VOS vs TEMPERATURE FIGURE 1. INPUT OFFSET VOLTAGE vs SUPPLY VOLTAGE 6 20 TEMPERATURE (°C) SUPPLY VOLTAGE (V) 60 50 VS = 5V 40 30 VS = 1.65V 20 10 0 -10 -20 -40 -20 0 20 40 60 80 TEMPERATURE (°C) FIGURE 5. MEDIAN IB- vs TEMPERATURE 6 100 10 0 VS = 5V -10 -20 VS = 1.65V -30 -40 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) FIGURE 6. MEDIAN IOS vs SUPPLY VOLTAGE vs TEMPERATURE FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 30 28 25 N = 30 26 VS = 1.65V SUPPLY CURRENT (µA) SUPPLY CURRENT (µA) N = 30 20 15 VS = 5V 10 5 24 22 MAX 20 MEDIAN 18 16 14 0 -40 -20 0 20 40 60 80 12 -40 100 VS = ±0.825V MIN -20 VIN = 0V RL =OPEN 0 TEMPERATURE (°C) 28 800 NORMALIZED GAIN (dB) SUPPLY CURRENT (µA) 1000 N = 30 24 22 20 18 MAX MEDIAN 16 14 12 -40 VS = ±2.5V VIN = 0V RL =OPEN MIN -20 0 20 40 60 TEMPERATURE (°C) 80 100 VS = 5V AV = 1 100 1 10 100 FREQUENCY (Hz) 1k 10k FIGURE 11. INPUT NOISE VOLTAGE DENSITY vs FREQUENCY 7 600 400 80 100 VS = 5V RL = 100k CL = 3.7pF Rg = 10, Rf = 100k AV = 10,000 200 0 -200 -400 -600 -1000 0 100k 50 100 150 200 250 300 350 400 450 500 FREQUENCY (Hz) FIGURE 10. INPUT NOISE VOLTAGE 0.1Hz TO 10Hz INPUT NOISE CURRENT (pA/√Hz) INPUT NOISE VOLTAGE (nV/√Hz) 1000 0.1 60 -800 FIGURE 9. SUPPLY CURRENT vs TEMPERATURE 10 0.001 0.01 40 FIGURE 8. SUPPLY CURRENT vs TEMPERATURE FIGURE 7. MEDIAN SUPPLY CURRENT vs TEMPERATURE vs SUPPLY VOLTAGE 26 20 TEMPERATURE (°C) 1.0 VS = 5V AV = 1 0.1 0.01 0.001 0.01 0.1 1 10 100 1k 10k 100k FREQUENCY (Hz) FIGURE 12. INPUT NOISE CURRENT DENSITY vs FREQUENCY FN6942.2 November 17, 2011 ISL28233I V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 200 OPEN LOOP GAIN (dB)/PHASE (°) OPEN LOOP GAIN (dB)/PHASE (°) Typical Performance Curves 150 PHASE 100 50 GAIN 0 RL = 10k CL = 100pF SIMULATION -50 -100 0.1m 1m 10m 100m 1 10 100 1k 10k 100k 1M 10M FREQUENCY (Hz) 200 150 100 50 -50 1 RL = 100k -1 RL = 1k -2 -3 RL = 10k -4 RL = 49.9k RL = OPEN -5 VS = ±0.8V CL = 3.7pF AV = +1 VOUT = 10mVP-P -9 100 1k NORMALIZED GAIN (dB) NORMALIZED GAIN (dB) 0 -8 10k 100k FREQUENCY (Hz) 1M RL = 10k RL = OPEN -3 -4 RL = 49.9k -5 -6 -7 VS = ±2.5V CL = 3.7pF AV = +1 VOUT = 10mVP-P 1k 10k 100k FREQUENCY (Hz) 1M 10M 1 NORMALIZED GAIN (dB) 0 8 Rf = Rg = 1k 7 GAIN (dB) -2 FIGURE 16. GAIN vs FREQUENCY vs RL, VS = ±2.5V 9 6 Rf = Rg = 10k 5 4 1 RL = 1k -1 -9 100 10M 10 2 10M RL = 100k 0 -8 FIGURE 15. GAIN vs FREQUENCY vs RL, VS = ±0.8V 3 RL = 10M CL = 100pF SIMULATION -100 0.1m 1m 10m 100m 1 10 100 1k 10k 100k 1M FREQUENCY (Hz) 1 -7 GAIN 0 FIGURE 14. FREQUENCY RESPONSE vs OPEN LOOP GAIN, RL = 10MΩ FIGURE 13. FREQUENCY RESPONSE vs OPEN LOOP GAIN, RL = 10kΩ -6 PHASE Rf = Rg = 100k VS = ±2.5V RL = 100k CL = 3.7pF AV = +2 VOUT = 10mVP-P 0 100 1k -1 -2 VOUT = 1V -3 -4 -5 -6 -7 VOUT = 500mV VOUT = 250mV VOUT = 100mV -8 10k 100k FREQUENCY (Hz) 1M FIGURE 17. GAIN vs FREQUENCY vs FEEDBACK RESISTOR VALUES Rf/Rg 8 10M -9 100 VOUT = 10mV 1k 10k 100k FREQUENCY (Hz) VS = ±2.5V RL = OPEN CL = 3.7pF AV = 1 1M 10M FIGURE 18. GAIN vs FREQUENCY vs VOUT, RL = OPEN FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 70 Rg = 100, Rf = 100k 0 NORMALIZED GAIN (dB) 60 1 AV = 1000 GAIN (dB) 50 40 Rg = 1k, Rf = 100k AV = 100 V+ = 5V CL = 3.7pF RL = 100k VOUT = 10mVP-P 30 20 AV = 10 Rg = 10k, Rf = 100k 10 0 AV = 1 -10 10 -1 -4 1k 10k 100k FREQUENCY (Hz) 1M -9 100 10M 1k 10k 100k FREQUENCY (Hz) 1M 10M FIGURE 20. GAIN vs FREQUENCY vs SUPPLY VOLTAGE 20 0 CL = 474pF -20 CMRR (dB) CL = 224pF 0 -2 -4 RL = 100k CL = 3.7pF AV = +1 VOUT = 10mVP-P -7 CL = 824pF CL = 104pF VS = ±2.5V -6 R = 100k L -8 AV = +1 VOUT = 10mVP-P -10 100 1k CL = 51pF 10k -40 VS = ±2.5V RL = 100k AV = +1 VCM = 1VP-P SIMULATION -60 -80 -100 CL = 3.7pF -120 100k 1M 10M -140 100 1k FREQUENCY (Hz) 10k 100k 1M 10M FREQUENCY (Hz) FIGURE 21. GAIN vs FREQUENCY vs CL FIGURE 22. CMRR vs FREQUENCY, VS = ±2.5V 0 -10 -20 -30 PSRR (dB) NORMALIZED GAIN (dB) 2 VS = ±2.75V -6 8 4 VS= ±1.5V -5 -8 FIGURE 19. FREQUENCY RESPONSE vs CLOSED LOOP GAIN 6 VS = ±0.8V -3 Rg = OPEN, Rf = 0 100 VS = ±0.7V -2 -40 -50 -60 PSRR+ -70 -80 PSRR- -90 -100 -110 10 100 VS = ±2.5V RL = 100k CL = 16.3pF AV = +1 VCM = 1VP-P 1k 10k 100k FREQUENCY (Hz) 1M 10M FIGURE 23. PSRR vs FREQUENCY, VS = ±2.5V 9 FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 0 180 -10 170 -20 CMRR (dB) PSRR (dB) 160 PSRR- -30 -40 -50 -60 VS = ±0.8V RL = 100k CL = 16.3pF AV = +1 VCM = 1VP-P -70 PSRR+ -80 -90 -100 10 100 1k 10k 100k FREQUENCY (Hz) 1M 140 120 100 -40 10M N = 60 60 80 100 350 400 3.5 SIGNAL (V) PSRR (dB) 40 4.0 MEDIAN MIN 100 -40 3.0 2.5 2.0 RL = 100k CL = 3.7pF AV = 1 VOUT = 4VP-P 1.5 1.0 VS = 2V to 5.5V 110 0.5 0 -20 0 20 40 60 TEMPERATURE (°C) 80 100 0 50 100 150 200 250 TIME (µs) 300 FIGURE 27. LARGE SIGNAL STEP RESPONSE (4V) FIGURE 26. PSRR vs TEMPERATURE 1.2 0.14 1.0 0.12 0.10 0.8 0.6 SIGNAL (V) SIGNAL (V) 20 4.5 MAX 130 RL = 100k CL = 3.7pF AV = 1 VOUT = 1VP-P 0.4 0.08 RL = 100k CL = 3.7pF AV = 1 VOUT = 100mVP-P 0.06 0.04 0.2 0 0 FIGURE 25. CMRR vs TEMPERATURE 160 120 -20 TEMPERATURE (°C) 170 140 N = 60 VS = ±2.5V VCM = ±2.6V MIN 110 5.0 190 150 MEDIAN 130 FIGURE 24. PSRR vs FREQUENCY, VS = ±0.8V 180 MAX 150 0.02 0 10 20 30 40 50 60 TIME (µs) 70 80 90 100 FIGURE 28. LARGE SIGNAL STEP RESPONSE (1V) 10 0 0 5 10 15 20 25 TIME (µs) 30 35 40 FIGURE 29. SMALL SIGNAL STEP RESPONSE (100mV) FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves 4.988 V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 24 N = 60 N = 60 4.986 22 MAX MEDIAN 4.982 4.980 VOL (mV) 20 MAX 18 MEDIAN MIN 16 VS = ±2.5V RL = 10kΩ 4.978 4.976 -40 -20 0 20 40 60 TEMPERATURE (°C) 80 MIN 14 -40 100 -20 -60 Vs = ±0.8V RL = OPEN CL = 3.7pF AV = 1 VOUT = 1VP-P -100 -110 -120 80 100 -80 -90 -100 -110 -130 -140 10 100 1k 10k FREQUENCY (Hz) 100k 1M FIGURE 32. CROSSTALK vs FREQUENCY, VS = ±0.8V -140 10 10 12 FREQUENCY (UNITS) 14 8 6 4 2 100 1k 10k FREQUENCY (Hz) 100k 1M FIGURE 33. CROSSTALK vs FREQUENCY, VS = ±2.5V 12 10 8 6 4 TCIOS (pA/°C) FIGURE 34. TCIOS HISTOGRAM 11 0. 70 0. 66 0. 62 0. 58 0. 54 0 0. 50 0. 32 0. 28 0. 24 0. 20 0. 16 0. 12 0. 08 0. 04 0 4 2 -0 . 0 FREQUENCY (UNITS) 60 -120 -130 0 40 Vs = ±2.5V RL = OPEN CL = 3.7pF AV = 1 VOUT = 1VP-P -70 0. 42 -90 20 -60 CROSSTALK (dB) CROSSTALK (dB) -80 0 FIGURE 31. VOL vs TEMPERATURE FIGURE 30. VOH vs TEMPERATURE -70 VS = ±2.5V RL = 10kΩ TEMPERATURE (°C) 0. 46 VOH (V) 4.984 TCIB (pA/°C) FIGURE 35. TCIb HISTOGRAM FN6942.2 November 17, 2011 ISL28233I Typical Performance Curves V+ = 5V, V- = 0V, VCM = 2.5V, RL = Open, T = +25°C, unless otherwise specified. (Continued) 50 INPUT OFFSET CURRENT (pA) FREQUENCY (UNITS) 16 14 12 10 8 6 4 2 0 -50 -42 -34 -26 -18 -10 -2 6 14 22 40 30 20 10 MEDIAN 0 -10 -20 MIN -30 -40 -50 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 30 COMMON MODE VOLTAGE (V) TCVOS (nV/°C) FIGURE 36. TCVOS HISTOGRAM FIGURE 37. IOS vs VCM 50 50 N = 10 30 20 MAX 10 0 MEDIAN -10 -20 MIN -30 -40 -50 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 COMMON MODE VOLTAGE (V) N = 10 40 IB- BIAS CURRENT (pA) 40 30 20 MAX 10 0 MEDIAN -10 -20 MIN -30 -40 -50 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 COMMON MODE VOLTAGE (V) FIGURE 39. IB- vs VCM FIGURE 38. IB+ vs VCM 10 INPUT OFFSET VOLTAGE (µV) IB+ BIAS CURRENT (pA) N = 10 MAX 8 N = 10 6 MAX 4 2 MEDIAN 0 -2 -4 MIN -6 -8 -10 -0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 COMMON MODE VOLTAGE (V) FIGURE 40. VOS vs VCM 12 FN6942.2 November 17, 2011 ISL28233I MAIN AMPLIFIER 5kHz CROSSOVER FILTER IN- VOUT IN+ CHOPPER STABILIZED DC OFFSET CORRECTION FIGURE 41. ISL28233IUZ FUNCTIONAL BLOCK DIAGRAM Applications Information Functional Description The ISL28233IUZ uses a proprietary chopper-stabilized technique (see Figure 41) that combines a 400kHz main amplifier with a very high open loop gain (174dB) chopper amplifier to achieve very low offset voltage and drift (2µV, 0.02µV/°C typical) while consuming only 18µA of supply current per channel. This multi-path amplifier architecture contains a time continuous main amplifier whose input DC offset is corrected by a parallel-connected, high gain chopper stabilized DC correction amplifier operating at 100kHz. From DC to ~5kHz, both amplifiers are active with DC offset correction and most of the low frequency gain is provided by the chopper amplifier. A 5kHz crossover filter cuts off the low frequency amplifier path leaving the main amplifier active out to the 400kHz gain-bandwidth product of the device. The key benefits of this architecture for precision applications are very high open loop gain, very low DC offset, and low 1/f noise. The noise is virtually flat across the frequency range from a few millihertz out to 100kHz, except for the narrow noise peak at the amplifier crossover frequency (5kHz). Rail-to-rail Input and Output (RRIO) The RRIO CMOS amplifier uses parallel input PMOS and NMOS that enable the inputs to swing 100mV beyond either supply rail. The inverting and non-inverting inputs do not have back-to-back input clamp diodes and are capable of maintaining high input impedance at high differential input voltages. This is effective in eliminating output distortion caused by high slew-rate input signals. The output stage uses common source connected PMOS and NMOS devices to achieve rail-to-rail output drive capability with 17mA current limit and the capability to swing to within 20mV of either rail while driving a 10kΩ load. IN+ and IN- Protection All input terminals have internal ESD protection diodes to both positive and negative supply rails, limiting the input voltage to within one diode beyond the supply rails. For applications where either input is expected to 13 exceed the rails by 0.5V, an external series resistor must be used to ensure the input currents never exceed 20mA (see Figure 42). RIN VIN + VOUT RL FIGURE 42. INPUT CURRENT LIMITING Layout Guidelines for High Impedance Inputs To achieve the maximum performance of the high input impedance and low offset voltage of the ISL28233IUZ, care should be taken in the circuit board layout. The PC board surface must remain clean and free of moisture to avoid leakage currents between adjacent traces. Surface coating of the circuit board will reduce surface moisture and provide a humidity barrier, reducing parasitic resistance on the board. The use of guard rings around the amplifier inputs will further reduce leakage currents. Figure 43 shows how the guard ring should be configured. The guard ring does not need to be a specific width, but it should form a continuous loop around both inputs. By setting the guard ring voltage equal to the voltage at the non-inverting input, parasitic capacitance is minimized as well. V+ HIGH IMPEDANCE INPUT ISL28433 IN + - GUARD RING PC TRACE FIGURE 43. USE OF GUARD RINGS TO REDUCE High Gain, Precision DC-Coupled Amplifier The circuit in Figure 44 implements a single-stage DC-coupled amplifier with an input DC sensitivity of under 100nV that is only possible using a low VOS amplifier with high open loop gain. High gain DC FN6942.2 November 17, 2011 ISL28233I amplifiers operating from low voltage supplies are not practical using typical low offset precision op amps. For example, the typical ±100µV VOS and offset drift 0.5µV/°C of a low offset op amp would produce a DC error of >1V with an additional 5mV/°C of temperature dependent error making it difficult to resolve DC input voltage changes in the mV range. The ±8µV max VOS and 0.06µV/°C of the ISL28233IUZ produces a temperature stable maximum DC output error of only ±80mV with a maximum temperature drift of 0.06µV/°C. The additional benefit of a very low 1/f noise corner frequency and some feedback filtering enables DC voltages and voltage fluctuations well below 100nV to be easily detected with a simple single stage amplifier. CF 0.018µF +2.5V VIN 1MΩ RL + The information in this SPICE model is protected under the United States copyright laws. Intersil Corporation hereby grants users of this macro-model hereto referred to as “Licensee”, a nonexclusive, nontransferable licence to use this model as long as the Licensee abides by the terms of this agreement. Before using this macro-model, the Licensee should read this license. If the Licensee does not accept these terms, permission to use the model is not granted. The Licensee may not sell, loan, rent, or license the macro-model, in whole, in part, or in modified form, to anyone outside the Licensee’s company. The Licensee may modify the macro-model to suit his/her specific applications, and the Licensee may make copies of this macro-model for use within their company only. This macro-model is provided “AS IS, WHERE IS, AND WITH NO WARRANTY OF ANY KIND EITHER EXPRESSED OR IMPLIED, INCLUDING BUY NOT LIMITED TO ANY IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.” 1MΩ, 100Ω LICENSE STATEMENT VOUT 100Ω -2.5V In no event will Intersil be liable for special, collateral, incidental, or consequential damages in connection with or arising out of the use of this macro-model. Intersil reserves the right to make changes to the product and the macro-model without prior notice. ACL = 10kV/V FIGURE 44. HIGH GAIN, PRECISION DC-COUPLED AMPLIFIER ISL28233IUZ SPICE Model Figure 45 shows the SPICE model schematic and Figure 46 shows the net list for the ISL28233IUZ SPICE model. The model is a simplified version of the actual device and simulates important parameters such as noise, Slew Rate, Gain and Phase. The model uses typical parameters from the “Electrical Specifications Table” on page 4. The poles and zeroes in the model were determined from the actual open and closed-loop gain and phase response. This enables the model to present an accurate AC representation of the actual device. The model is configured for ambient temperature of +25°C. Figures 47 through 54 show the characterization vs simulation results for the Noise Density, Frequency Response vs Close Loop Gain, Gain vs Frequency vs CL and Large Signal Step Response (4V). 14 FN6942.2 November 17, 2011 ISL28233I V16 V15 Dn2 7 Dn1 I2 R22 I1 R21 R1 R2 + - + - Vin+ M1 En M2 Cin1 Cin2 13 Vin- 12 R3 R4 4 Input Stage Voltage Noise 7 7 + + D2 R6 - R8 - G2 D4 C1 G4 V4 V6 13 VV3 12 16 - V3 G1 - R5 D1 + V5 G3 R7 C2 + D3 4 4 SR Limit & First Pole Gain Stage 7 + - R12 L1 + G8 G5 D7 R14 + D8 G10 C3 V+ R16 R11 VV3 Vout 16 R10 E1 + + - G7 - G5 + 4 R9 L2 R13 + C4 G9 + - D6 D5 G10 + - G11 + R15 VZero/Pole Pole Output Stage FIGURE 45. SPICE CIRCUIT SCHEMATIC 15 FN6942.2 November 17, 2011 ISL28233I * ISL28233 Macromodel * Revision B, April 2009 * AC characteristics, Voltage Noise *Copyright 2009 by Intersil Corporation *Refer to data sheet “LICENSE STATEMENT” Use of *this model indicates your acceptance with the *terms and provisions in the License Statement. * Connections: +input * | -input * | | +Vsupply * | | | -Vsupply * | | | | output * | | | | | .subckt ISL28233 3 2 7 4 6 * *Voltage Noise D_DN1 102 101 DN D_DN2 104 103 DN R_R21 0 101 120k R_R22 0 103 120k E_EN 8 3 101 103 1 V_V15 102 0 0.1Vdc V_V16 104 0 0.1Vdc * *Input Stage C_Cin1 8 0 0.4p C_Cin2 2 0 2.0p R_R1 9 10 10 R_R2 10 11 10 R_R3 4 12 100 R_R4 4 13 100 M_M1 12 8 9 9 pmosisil + L=50u + W=50u M_M2 13 2 11 11 pmosisil + L=50u + W=50u I_I1 4 7 DC 92uA I_I2 7 10 DC 100uA * *Gain stage G_G1 4 VV2 13 12 0.0002 G_G2 7 VV2 13 12 0.0002 R_R5 4 VV2 1.3Meg R_R6 VV2 7 1.3Meg D_D1 4 14 DX D_D2 15 7 DX V_V3 VV2 14 0.7Vdc V_V4 15 VV2 0.7Vdc * *SR limit first pole G_G3 4 VV3 VV2 16 1 G_G4 7 VV3 VV2 16 1 R_R7 4 VV3 1meg R_R8 VV3 7 1meg C_C1 VV3 7 12u C_C2 4 VV3 12u D_D3 4 17 DX D_D4 18 7 DX V_V5 VV3 17 0.7Vdc V_V6 18 VV3 0.7Vdc * *Zero/Pole E_E1 16 4 7 4 0.5 G_G5 4 VV4 VV3 16 0.000001 G_G6 7 VV4 VV3 16 0.000001 L_L1 20 7 0.3H R_R12 20 7 2.5meg R_R11 VV4 20 1meg L_L2 4 19 0.3H R_R9 4 19 2.5meg R_R10 19 VV4 1meg *Pole G_G7 4 VV5 VV4 16 0.000001 G_G8 7 VV5 VV4 16 0.000001 C_C3 VV5 7 0.12p C_C4 4 VV5 0.12p R_R13 4 VV5 1meg R_R14 VV5 7 1meg * *Output Stage G_G9 21 4 6 VV5 0.0000125 G_G10 22 4 VV5 6 0.0000125 D_D5 4 21 DY D_D6 4 22 DY D_D7 7 21 DX D_D8 7 22 DX R_R15 4 6 8k R_R16 6 7 8k G_G11 6 4 VV5 4 -0.000125 G_G12 7 6 7 VV5 -0.000125 * .model pmosisil pmos (kp=16e-3 vto=10m) .model DN D(KF=6.4E-16 AF=1) .MODEL DX D(IS=1E-18 Rs=1) .MODEL DY D(IS=1E-15 BV=50 Rs=1) .ends ISL28233 FIGURE 46. SPICE NET LIST 16 FN6942.2 November 17, 2011 ISL28233I Characterization vs Simulation Results 1000 1000 V+ = 5V AV = 1 100 10 0.001 0.01 0.1 1 10 100 1k 10k 100k INPUT NOISE VOLTAGE (nV/√Hz INPUT NOISE VOLTAGE (nV/√Hz v V+ = 5V AV = 1 100 10 0.1 1 FREQUENCY (Hz) 70 Rg = 100, Rf = 100k 40 V+ = 5V CL = 3.7pF RL = 100k VOUT = 10mVP-P 30 20 AV = 10 Rg = 10k, Rf = 100k 10 0 50 Rg = 1k, Rf = 100k AV = 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 4 2 0 -2 -4 V+ = 5V CL = 104pF -6 RL = 100k CL = 51pF AV = +1 -8 V OUT = 10mVP-P CL = 3.7pF -10 100 1k 10k 100k FREQUENCY (Hz) 1M 10M FIGURE 51. CHARACTERIZED GAIN vs FREQUENCY vs CL 17 Rg = 10k, Rf = 100k AV = 10 20 AV = 1 -10 10 Rg = 10M Rf = 1 100 1k 10k 100k FREQUENCY (Hz) 1M 10M FIGURE 50. SIMULATED FREQUENCY RESPONSE vs CLOSED LOOP GAIN NORMALIZED GAIN (dB) NORMALIZED GAIN (dB) 30 8 CL = 824pF CL CL = 474pF CL = 224pF 6 Rg = 1k, Rf = 100k 0 FIGURE 49. CHARACTERIZED FREQUENCY RESPONSE vs CLOSED LOOP GAIN 8 100k AV = 100 10 Rg = OPEN, Rf = 0 100 10k Rg = 100, Rf = 100k 40 AV = 1 -10 10 AV = 1000 60 GAIN (dB) GAIN (dB) 50 1k FIGURE 48. SIMULATED INPUT NOISE VOLTAGE DENSITY vs FREQUENCY 70 60 100 FREQUENCY (Hz) FIGURE 47. CHARACTERIZED INPUT NOISE VOLTAGE DENSITY vs FREQUENCY AV = 1000 10 CL = 824pF 6 CL = 474pF 4 CL C L = 224pF 2 0 -2 -4 -6 CL = 3.7pF -8 -10 100 1k 10k 100k FREQUENCY (Hz) 1M 10M FIGURE 52. SIMULATED GAIN vs FREQUENCY vs CL FN6942.2 November 17, 2011 ISL28233I 5.0 5.0 4.5 4.5 4.0 4.0 LARGE SIGNAL (V) LARGE SIGNAL (V) Characterization vs Simulation Results (Continued) 3.5 3.0 V+ = 5V RL = 100k CL = 3.7pF AV = 1 VOUT = 4VP-P 2.5 2.0 1.5 1.0 0.5 0 VIN 3.5 VOUT 3.0 2.5 2.0 1.5 1.0 0.5 0 50 100 150 200 250 300 350 400 0 0 50 100 150 TIME (µs) FIGURE 53. CHARACTERIZED LARGE SIGNAL STEP RESPONSE (4V) 200 250 300 350 400 TIME (µs) FIGURE 54. SIMULATED LARGE SIGNAL STEP RESPONSE (4V) Revision History The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to web to make sure you have the latest Rev. DATE REVISION CHANGE 10/8/11 FN6942.2 Removed “UZ” from Device number top of all pages. 8/23/10 FN6942.1 Removed all ISL28433 device information from data sheet. Stamped not recommended for new designs since these parts are going to be obsolete. Recommended replacement part ISL28233FUZ. 3/25/10 FN6942.0 Initial Release. Products Intersil Corporation is a leader in the design and manufacture of high-performance analog semiconductors. The Company's products address some of the industry's fastest growing markets, such as, flat panel displays, cell phones, handheld products, and notebooks. Intersil's product families address power management and analog signal processing functions. Go to www.intersil.com/products for a complete list of Intersil product families. *For a complete listing of Applications, Related Documentation and Related Parts, please see the respective device information page on intersil.com: ISL28233I To report errors or suggestions for this datasheet, please go to www.intersil.com/askourstaff FITs are available from our website at http://rel.intersil.com/reports/search.php For additional products, see www.intersil.com/product_tree Intersil products are manufactured, assembled and tested utilizing ISO9000 quality systems as noted in the quality certifications found at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 18 FN6942.2 November 17, 2011 ISL28233I Package Outline Drawing M8.118A 8 LEAD MINI SMALL OUTLINE PLASTIC PACKAGE (MSOP) Rev 0, 9/09 3.0±0.1 8 A 0.25 CAB 3.0±0.1 4.9±0.15 DETAIL "X" 1.10 Max PIN# 1 ID B SIDE VIEW 2 1 0.18 ± 0.05 2 0.65 BSC TOP VIEW 0.95 BSC 0.86±0.09 H GAUGE PLANE C 0.25 SEATING PLANE 0.33 +0.07/ -0.08 0.08 C A B 0.10 ± 0.05 3°±3° 0.10 C 0.55 ± 0.15 DETAIL "X" SIDE VIEW 1 5.80 NOTES: 4.40 3.00 1. Dimensions are in millimeters. 2. Dimensioning and tolerancing conform to JEDEC MO-187-AA and AMSE Y14.5m-1994. 3. Plastic or metal protrusions of 0.15mm max per side are not included. 4. Plastic interlead protrusions of 0.25mm max per side are not included. 5. Dimensions “D” and “E1” are measured at Datum Plane “H”. 6. This replaces existing drawing # MDP0043 MSOP 8L. 0.65 0.40 1.40 TYPICAL RECOMMENDED LAND PATTERN 19 FN6942.2 November 17, 2011