LT1881/LT1882 Dual and Quad Rail-to-Rail Output, Picoamp Input Precision Op Amps DESCRIPTION FEATURES

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1 FEATURES n Offset Votage: 5 Maximum (LT88A) n Input Bias Current: 2 Maximum (LT88A) n Offset Votage Drift:.8/ C Maximum n Rai-to-Rai Output Swing n Suppy Range: 2.7V to 36V n Operates with Singe or Spit Suppies n Open-Loop Votage Gain: Miion Minimum n Maximum Suppy Current Per Ampifi er n Stabe at A V =, C L = pf n Standard Pinouts n Wide Operating Temperature Range: 55 C to 25 C (LT882) APPLICATIONS n Thermocoupe Ampifi ers n Bridge Transducer Conditioners n Instrumentation Ampifi ers n Battery-Powered Systems n Photo Current Ampifi ers L, LT, LTC, LTM, Linear Technoogy and the Linear ogo are registered trademarks of Linear Technoogy Corporation. A other trademarks are the property of their respective owners. LT88/LT882 Dua and Quad Rai-to-Rai Output, Picoamp Input Precision Op Amps DESCRIPTION The LT 88 and LT882 op amps bring high accuracy input performance to ampifi ers with rai-to-rai output swing. Input bias currents and capacitive oad driving capabiities are superior to the simiar LT884 and LT885 ampifiers, at the cost of a sight oss in speed. Input offset votage is trimmed to ess than 5 and the ow drift maintains this accuracy over the operating temperature range. Input bias currents are an utraow 2 maximum. The ampifi ers work on any tota power suppy votage between 2.7V and 36V (fuy specified from 5V to ±5V). Output votage swings to within 4 of the negative suppy and 22 of the positive suppy make these ampifiers good choices for ow votage singe suppy operation. Capacitive oads up to pf can be driven directy in unity-gain foower appications. The dua LT88 and LT88A are avaiabe with standard pinouts in S8 and PDIP packages. The quad LT882 is in a 4-pin SO package. For a higher speed device with simiar DC specifications, see the LT884/LT885. TYPICAL APPLICATION.65k LT V R 6-Bit Votage Output DAC on ±5V Suppy + 5V LT88 5V R COM REF LTC 597 5V R OFS DAC 33pF + 5V LT88 5V PERCENT OF UNITS (%) V OUT 4.96V TO 4.96V 882 TAa 4 N8 ( LOT) 44 S8 (2 LOTS) 84 TOTAL PARTS TC V OS Distribution, Industria Grade INPUT OFFSET VOLTAGE DRIFT (/ C) 882 TAb

2 LT88/LT882 ABSOLUTE MAXIMUM RATINGS Suppy Votage (V + to V )...4V Differentia Input Votage (Note 2)...±V Input Votage... V + to V Input Current (Note 2)...± Output Short-Circuit Duration (Note 3)... Indefinite Operating Temperature Range (Note 4) LT88C/LT882C... 4 C to 85 C LT88I/LT882I... 4 C to 85 C LT882H... 4 C to 25 C LT882MP C to 25 C (Note ) Specified Temperature Range (Note 5) LT88C/LT882C... 4 C to 85 C LT88I/LT882I... 4 C to 85 C LT882H... 4 C to 25 C LT882MP C to 25 C Maximum Junction Temperature... 5 C Storage Temperature Range C to 5 C Lead Temperature (Sodering, sec)... 3 C PIN CONFIGURATION TOP VIEW OUT A IN A 2 +IN A 3 V 4 N8 PACKAGE 8-LEAD PDIP A TOP VIEW B V+ OUT B IN B +IN B S8 PACKAGE 8-LEAD PLASTIC SO T JMAX = 5 C, θ JA = 3 C/W (N8) T JMAX = 5 C, θ JA = 9 C/W (S8) OUT A IN A 2 +IN A 3 V+ 4 +IN B 5 IN B 6 OUT B 7 A B D 4 OUT D 3 IN D 2 +IN D V +IN C 9 IN C 8 OUT C S PACKAGE 4-LEAD PLASTIC SO T JMAX = 5 C, θ JA = 6 C/W C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT88CN8#PBF LT88CN8#TRPBF LT88CN8 8-Lead PDIP C to 7 C LT88IN8#PBF LT88IN8#TRPBF LT88IN8 8-Lead PDIP 4 C to 85 C LT88CS8#PBF LT88CS8#TRPBF 88 8-Lead Pastic SO C to 7 C LT88IS8#PBF LT88IS8#TRPBF 88I 8-Lead Pastic SO 4 C to 85 C LT88ACN8#PBF LT88ACN8#TRPBF LT88ACN8 8-Lead PDIP C to 7 C LT88AIN8#PBF LT88AIN8#TRPBF LT88AIN8 8-Lead PDIP 4 C to 85 C LT88ACS8#PBF LT88ACS8#TRPBF 88A 8-Lead Pastic SO C to 7 C LT88AIS8#PBF LT88AIS8#TRPBF 88AI 8-Lead Pastic SO 4 C to 85 C LT882CS#PBF LT882CS#TRPBF LT882CS 4-Lead Pastic SO C to 7 C LT882IS#PBF LT882IS#TRPBF LT882IS 4-Lead Pastic SO 4 C to 85 C LT882HS#PBF LT882HS#TRPBF LT882HS 4-Lead Pastic SO 4 C to 25 C LT882MPS#PBF LT882MPS#TRPBF LT882MPS 4-Lead Pastic SO 55 C to 25 C Consut LTC Marketing for parts specifi ed with wider operating temperature ranges. For more information on ead free part marking, go to: For more information on tape and ree specifi cations, go to: 2

3 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER CONDITIONS V OS Input Offset Votage (LT88A) C < T A < 7 C 4 C < T A < 85 C Input Offset Votage (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔV OS /ΔT Input Offset Votage Drift C < T A < 7 C (Note 6) 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔV OS / ΔTIME I OS Long-Term Input Offset Votage Stabiity Input Offset Current (LT88A) Input Offset Current (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C C/I Grades LT88/LT882 The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Singe suppy operation V S = 5V, V; V CM = V S /2 uness otherwise noted. (Note 5) I B Input Bias Current (LT88A) Input Bias Current (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C H/MP Grades MIN TYP MAX MIN TYP MAX UNITS / C / C / C / C.3.3 /month Input Noise Votage.Hz to Hz.5.5 P-P e n Input Noise Votage Density f = khz 4 4 nv/ Hz i n Input Noise Current Density f = khz.3.3 / Hz R IN Input Resistance Differentia Mode Common Mode C IN Input Capacitance 2 2 pf V CM Input Votage Range V +. V+. V +. V+. V V +.2 V+.2 V +.2 V+.2 V CMRR Common Mode Rejection Ratio V < V CM < 4V.2V < V CM < 3.8V MΩ GΩ 28 db db PSRR Power Suppy Rejection Ratio V = V, V CM =.5V C < T A < 85 C, 2.7V < V + < 32V 6 db C < T A < 25 C, 2.7V < V + < 32V 6 db T A = 4 C, 3V < V + < 32V 6 db T A = 55 C, 3V < V + < 32V 6 db Minimum Operating Suppy Votage V 3

4 LT88/LT882 ELECTRICAL CHARACTERISTICS The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Singe suppy operation V S = 5V, V; V CM = V S /2 uness otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS A VOL Large-Signa Votage Gain R L = k; V < V OUT < 4V R L = 2k; V < V OUT < 4V R L = k; V < V OUT < 4V V OL Output Votage Swing Low No Load I SINK = μa I SINK = I SINK = 5 V OH Output Votage Swing High (Referred to V + ) No Load I SINK = μa I SINK = I SINK = 5 I S Suppy Current Per Ampifi er V S = 3V, V V S = 5V, V V S = 2V, V I SC Short-Circuit Current V OUT Short to GND V OUT Short to V + C/I Grades H/MP Grades MIN TYP MAX MIN TYP MAX UNITS 6 V/ V/ 8 V/ V/ 4 V/ V/ GBW Gain Bandwidth Product f = 2kHz MHz Channe Separation f = khz 2 2 db t S Setting Time.%, V OUT =.5V to 3.5V, 3 3 μs A V =, R L = 2k SR + Sew Rate Positive A V = V/μs.2. V/μs SR Sew Rate Negative A V = V/μs.8.6 V/μs FPBW Fu-Power Bandwidth V OUT = 4V P-P (Note ) ΔV OS ΔI B + Offset Votage Match (LT88A) Offset Votage Match (LT88/LT882) (Note 7) C < T A < 7 C 4 C < T A < 85 C (Note 7) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C khz khz Offset Votage Match Drift (Notes 6, 7) / C Noninverting Bias Current Match (LT88A) (Note 7) C < T A < 7 C 4 C < T A < 85 C

5 LT88/LT882 ELECTRICAL CHARACTERISTICS The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Singe suppy operation V S = 5V, V; V CM = V S /2 uness otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS ΔI B + Noninverting Bias Current Match (Note 7) (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔCMRR ΔPSRR Common Mode Rejection Ratio Match Power Suppy Rejection Match (Notes 7, 9) C/I Grades H/MP Grades MIN TYP MAX MIN TYP MAX UNITS (Notes 7, 9) db V = V, V CM =.5V C < T A < 85 C, 2.7V < V + < 32V C < T A < 25 C, 2.7V < V + < 32V T A = 4 C, 3V < V + < 32V T A = 55 C, 3V < V + < 32V db db db db The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Spit suppy operation, V CM = V uness otherwise noted. (Note 5) SYMBOL PARAMETER CONDITIONS V OS Input Offset Votage (LT88A) C < T A < 7 C 4 C < T A < 85 C Input Offset Votage (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔV OS /ΔT Input Offset Votage Drift C < T A < 7 C (Note 6) 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔV OS / ΔTIME I OS I B Long-Term Input Offset Votage Stabiity Input Offset Current (LT88A) C < T A < 7 C 4 C < T A < 85 C Input Offset Current (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C Input Bias Current (LT88A) C < T A < 7 C 4 C < T A < 85 C Input Bias Current (LT88/LT882) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C C/I Grades H/MP Grades MIN TYP MAX MIN TYP MAX UNITS / C / C / C / C.3.3 /month

6 LT88/LT882 ELECTRICAL CHARACTERISTICS The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Spit suppy operation, V CM = V uness otherwise noted. (Note 5) C/I Grades H/MP Grades SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS Input Noise Votage.Hz to Hz.5.5 P-P e n Input Noise Votage Density f = khz 4 4 nv/ Hz i n Input Noise Current Density f = khz.3.3 / Hz R IN Input Resistance Differentia Mode Common Mode C IN Input Capacitance 2 2 pf V CM Input Votage Range V +. V +. V +. V +. V V +.2 V +.2 V +.2 V +.2 V CMRR Common Mode Rejection Ratio 3.5V < V CM < 3.5V db +PSRR Positive Power Suppy Rejection Ratio V = 5V, V CM = V;.5V < V + < 8V db PSRR Negative Power Suppy Rejection Ratio Minimum Operating Suppy Votage V + = 5V, V CM = V;.5V < V < 8V A VOL Large-Signa Votage Gain R L = k; 3.5V < V OUT < 3.5V V OL V OH Output Votage Swing Low (Referred to V EE ) Output Votage Swing High (Referred to V CC ) R L = 2k; 3.5V < V OUT < 4V R L = k; V < V OUT < 4V No Load I SINK = μa I SINK = I SINK = 5 No Load I SOURCE = μa I SOURCE = I SOURCE = MΩ GΩ db ±.2 ±.35 ±.2 ±.35 V V/ V/ 42 V/ V/ 23 V/ V/ I S Suppy Current Per Ampifi er I SC Short-Circuit Current V OUT Short to V V OUT Short to V GBW Gain Bandwidth Product f = 2kHz MHz Channe Separation f = khz 2 2 db t S Setting Time.%, V OUT = 5V to 5V, 3 3 μs A V =, R L = 2k SR + Sew Rate Positive A V = V/μs.8.5 V/μs SR Sew Rate Negative A V = V/μs..7 V/μs

7 ELECTRICAL CHARACTERISTICS SYMBOL PARAMETER CONDITIONS FPBW Fu-Power Bandwidth V OUT = 28V P-P (Note ) ΔV OS Offset Votage Match (Note 7) (LT88A) C < T A < 7 C 4 C < T A < 85 C C/I Grades LT88/LT882 The denotes the specifi cations which appy over the fu operating temperature range, otherwise specifi cations are at T A = 25 C. Spit suppy operation, V CM = V uness otherwise noted. (Note 5) ΔI B + ΔI B + Offset Votage Match (LT88/LT882) (Note 7) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C H/MP Grades MIN TYP MAX MIN TYP MAX UNITS 2.25 khz khz Offset Votage Match Drift (Notes 6, 7) / C Noninverting Bias Current Match (LT88A) Noninverting Bias Current Match (LT88/LT882) (Note 7) C < T A < 7 C 4 C < T A < 85 C (Note 7) C < T A < 7 C 4 C < T A < 85 C 4 C < T A < 25 C 55 C < T A < 25 C ΔCMRR Common Mode Rejection Match (Notes 7, 9) db 2 2 Δ+PSRR Δ PSRR Positive Power Suppy Rejection Ratio Match Negative Power Suppy Rejection Ratio Match V = 5V, V CM = V,.5V < V + < 8V, (Notes 7, 9) V + = 5V, V CM = V,.5V < V < 8V, (Notes 7, 9) db db Note : Stresses beyond those isted under Absoute Maximum Ratings may cause permanent damage to the device. Exposure to any Absoute Maximum Rating condition for extended periods may affect device reiabiity and ifetime. Note 2: The inputs are protected by interna resistors and back-to-back diodes. If the differentia input votage exceeds ±.7V, the input current shoud be imited externay to ess than. Note 3: A heat sink may be required to keep the junction temperature beow absoute maximum. Note 4: The LT88C/LT882C and LT88I/LT882I are guaranteed functiona over the operating temperature range of 4 C to 85 C. The LT882H is guaranteed functiona over the operating temperature range 4 C to 25 C. The LT882MP is guaranteed functiona over the operating temperature range 55 C to 25 C. Note 5: The LT88C/LT882C are guaranteed to meet specifi ed performance from C to 7 C. The LT88C/LT882C are designed, characterized and expected to meet specifi ed performance from 4 C to 85 C but are not tested or QA samped at these temperatures. The LT88I/LT882I are guaranteed to meet specifi ed performance from 4 C to 85 C. The LT882H is guaranteed to meet specifi ed performance from 4 C to 25 C. The LT882MP is guaranteed to meet specifi ed performance from 55 C to 25 C. Note 6: This parameter is not % tested. Note 7: Matching parameters are the difference between ampifiers A and B in the LT88; and between ampifi ers A and D and B and C in the LT882. Note 8: This parameter is the difference between the two noninverting input bias currents. Note 9: ΔCMRR and ΔPSRR are defi ned as foows: CMRR and PSRR are measured in /V on each ampifi er. The difference is cacuated in /V and then converted to db. Note : Fu power bandwidth is cacuated from the sew rate: FPBW = SR/2πV P. 7

8 LT88/LT882 TYPICAL PERFORMANCE CHARACTERISTICS SUPPLY CURRENT PER AMPLIFIER (μa) Suppy Current per Ampifi er vs Suppy Votage Sew Rate vs Suppy Votage Sew Rate vs Temperature 25 C 25 C 55 C SLEW RATE (V/μs) A V = RISING FALLING SLEW RATE (V/μs) A V = RISING FALLING V S = ±5V V S = ±5V TOTAL SUPPLY VOLTAGE (V) TOTAL SUPPLY VOLTAGE (V) TEMPERATURE ( C) 882 G 882 G2 882 G3 OUTPUT STEP (V) Setting Time vs Output Step A V =.%.%.%.% SETTLING TIME (μs) 882 G4 OUTPUT STEP (V) Setting Time vs Output Step A V =.%.%.%.% SETTLING TIME (μs) 882 G5 GAIN BANDWIDTH PRODUCT (khz) Gain Bandwidth Product vs Suppy Votage 25 C 25 C 55 C TOTAL SUPPLY VOLTAGE (V) 882 G6 Phase Margin vs Suppy Votage Gain vs Frequency, A V = Gain vs Frequency, A V = 6 PHASE MARGIN (DEG) C 25 C 25 C GAIN (db) 2 3 V S = ±2.5V GAIN (db) 2 3 V S = ±2.5V TOTAL SUPPLY VOLTAGE (V) 4 k k k M M M 4 k k k M M M 882 G7 882 G8 882 G9 8

9 LT88/LT882 TYPICAL PERFORMANCE CHARACTERISTICS Gain vs Frequency with C LOAD, A V = Gain vs Frequency with C LOAD, A V = 5pF 8pF GAIN (db) 2 pf 5pF pf GAIN (db) 2 pf 5pF 3 3 pf 4 k k k M M M 4 k k k M M M 882 G 882 G Large Signa Response, A V = Large Signa Response, A V = Sma Signa Response, A V =, No Load V OUT (5V/DIV) V OUT (5V/DIV) V OUT (2/DIV) TIME (5μs/DIV) 882 G2 TIME (5μs/DIV) 882 G3 TIME (2μs/DIV) 882 G4 Sma Signa Response, A V =, C L = pf Sma Signa Response, A V =, R L = 2k Sma Signa Response, A V =, C L = 5pF V OUT (2/DIV) V OUT (2/DIV) V OUT (2/DIV) TIME (2μs/DIV) 882 G5 TIME (2μs/DIV) 882 G6 TIME (2μs/DIV) 882 G7 9

10 LT88/LT882 TYPICAL PERFORMANCE CHARACTERISTICS PERCENT OF UNITS (%) V OS Distribution, T A = 25 C Votage Offset vs Temperature Warm-Up Drift vs Time 4 N8 ( LOT) 44 S8 (2 LOTS) 84 TOTAL PARTS VOLTAGE OFFSET () OFFSET VOLTAGE DRIFT () N8 V S = 5V N8 S8 V S = 5V, ±5V OUTPUT OFFSET VOLTAGE () 882 G TEMPERATURE ( C) 882 G TIME AFTER POWER UP (s) 882 G2 I BIAS () Input Bias Current vs Common Mode Votage V CM (V) INPUT BIAS CURRENT () Input Bias Current vs Temperature +I BIAS I BIAS TEMPERATURE ( C) INPUT COMMON MODE RANGE (V) V + V +.2 V +.4 V +.6 V +.8 V +.8 V +.6 V +.4 V +.2 Input Common Mode Range vs Suppy Votage V OS 55 C 4 C 25 C V SUPPLY VOLTAGE (±V) 85 C 25 C 882 G2 882 G G23 INPUT COMMON MODE LIMIT (V) Input Common Mode Range vs Temperature UPPER LIMIT V S = ±5V V OS < LOWER LIMIT TEMPERATURE ( C) OUTPUT VOLTAGE SWING (V) V + V +.5 V +. V +. V +.5 Output Votage Swing vs Suppy Votage A V = T A = 25 C SUPPLY VOLTAGE (±V) R L = k R L = 2k R L = 2k R L = k V OUTPUT SATURATION VOLTAGE (V)... Output Saturation Votage vs Load Current (Output High) V OVERDRIVE = 3 T A = 55 C T A = 4 C T A = 25 C T A = 85 C T A = 25 C.. SOURCING LOAD CURRENT () 882 G G G26

11 TYPICAL PERFORMANCE CHARACTERISTICS LT88/LT882 OUTPUT SATURATION VOLTAGE (V). Output Saturation Votage vs Load Current (Output Low) V OVERDRIVE = 3 T A = 55 C. T A = 4 C T A = 25 C T A = 85 C T A = 25 C.... SINKING LOAD CURRENT () OUTPUT SHORT-CIRCUIT CURRENT () Output Short-Circuit Current vs Temperature SINKING SOURCING TEMPERATURE ( C) V IN V OUT Output Votage vs Large Input Votage A V = V S = ±2.5V V IN = ±5V R IN = k 882 G29 GND GND 882 G G28 LOOP GAIN (db) Open-Loop Gain vs Frequency k k k M MM LOOP GAIN (db) k Open-Loop Gain and Phase vs Frequency V S = ±5V LOOP GAIN PHASE k k M M PHASE (DEG) CHANNEL SEPARATION (db) Channe Separation vs Frequency A V = 4 k k k M M M 882 G3 882 G3 882 G32 GAIN BANDWIDTH PRODUCT (khz) Gain Bandwidth Product vs Temperature Output Impedance vs Frequency PSRR vs Frequency V S = ±2.5V TEMPERATURE ( C) 882 G33 OUTPUT IMPEDANCE (Ω).. V S = ±2.5V A V = A V = A V =. k k k 882 G34 PSSR (db) PSSR 7 6 +PSSR k k k M 882 G35

12 LT88/LT882 TYPICAL PERFORMANCE CHARACTERISTICS CMRR (db) Common Mode Rejection Ratio vs Frequency.Hz to Hz Noise Noise Votage vs Frequency. k k k M NOISE VOLTAGE (.2/DIV) s/div NOISE VOLTAGE DENSITY (nv/vhz) V S = ±5V A V = k 88/2 G G G38 NOISE CURRENT DENSITY (fa/ Hz) Noise Current Density vs Frequency Tota Noise vs Source Resistance Overshoot vs Capacitive Load TOTAL INPUT REFERRED NOISE (nv/ Hz) k k k M R S (Ω) OVERSHOOT (%) R L = k A V = A V = k k CAPACITIVE LOAD (pf) 882 G G4 882 G4 SERIES OUTPUT RESISTANCE (Ω) Series Output Resistance vs Capacitive Load A V = T A = 25 C V S = ±2.5V PEAK-TO-PEAK OUTPUT VOLTAGE (V) Undistorted Output Swing vs Frequency A V = T A = 25 C V S = ±2.5V A V = T A = 25 C THD + NOISE (%)... THD + Noise vs Frequency V IN = 2V P-P A V = A V = CAPACITIVE LOAD (pf) FREQUENCY (khz). k k k 88/2 G G G44 2

13 TYPICAL PERFORMANCE CHARACTERISTICS LT88/LT882 THD + NOISE (%)... m Tota Harmonic Distortion + Noise vs Output Votage Ampitude A V = V S = ±2.5V A V = 2 V S = ±2.5V A V = A V = 2 f = khz RF = RG = k. OUTPUT VOLTAGE AMPLITUDE (V P-P ) 882 G45 CHANGE IN INPUT OFFSET VOLTAGE (2/DIV) Open-Loop Gain R L = 2k R L = 5k R L = k OUTPUT VOLTAGE (5V/DIV) 882 G46 Setting Time/Output Step.% Setting Time/Output Step.% GND V V GND.5/DIV.5/DIV A V = 2μs/DIV 882 G47 A V = 5μs/DIV 882 G48 Gain vs Temperature 6. V S = ±5V 5. V TO V V TO V. Gain vs Load Resistance +A VOL (V TO V) 4. A VOL (V TO V) GAIN (V/) R L = k GAIN (V/).. R L = 2k TEMPERATURE ( C) 882 G LOAD RESISTANCE (kω) 882 G5 3

14 LT88/LT882 APPLICATIONS INFORMATION The LT88 dua and LT882 quad op amps feature exceptiona input precision with rai-to-rai output swing. The ampifiers are simiar to the LT884 and LT885 devices. The LT88 and LT882 offer superior capacitive oad driving capabiities over the LT884 and LT885 in ow votage gain configurations. Offset votages are trimmed to ess than 5 and input bias currents are ess than 2 on the A grade devices. Obtaining beneficia advantage of these precision input characteristics depends upon proper appications circuit design and board ayout. Preserving Input Precision Preserving the input votage accuracy of the LT88/LT882 requires that the appications circuit and PC board ayout do not introduce errors comparabe to or greater than the 3 offset. Temperature differentias across the input connections can generate thermocoupe votages of s of microvots. PC board ayouts shoud keep connections to the ampifier s input pins cose together and away from heat dissipating components. Air currents across the board can aso generate temperature differentias. The extremey ow input bias currents, 5, aow high accuracy to be maintained with high impedance sources and feedback networks. The LT88/LT882 s ow input bias currents are obtained by using a canceation circuit on-chip. This causes the resuting I BIAS + and I BIAS to be uncorreated, as impied by the I OS specifi cation being greater than the I BIAS. The user shoud not try to baance the input resistances in each input ead, as is commony recommended with most ampifiers. The impedance at either input shoud be kept as sma as possibe to minimize tota circuit error. PC board ayout is important to insure that eakage currents do not corrupt the ow I BIAS of the ampifier. In high precision, high impedance circuits, the input pins shoud be surrounded by a guard ring of PC board interconnect, with the guard driven to the same common mode votage as the ampifier inputs. Input Common Mode Range The LT88 and LT882 outputs are abe to swing neary to each power suppy rai, but the input stage is imited to operating between V +V and V + V. Exceeding this common mode range wi cause the gain to drop to zero; however, no phase reversa wi occur. Input Protection The inverting and noninverting input pins of the LT88 and LT882 have imited on-chip protection. ESD protection is provided to prevent damage during handing. The input transistors have votage camping and imiting resistors to protect against input differentias up to V. Short transients above this eve wi aso be toerated. If the input pins can see a sustained differentia votage above V, externa imiting resistors shoud be used to prevent damage to the ampifier. A k resistor in each input ead wi provide protection against a 3V differentia votage. Capacitive Loads The LT88 and LT882 can drive capacitive oads up to pf in unity-gain. The capacitive oad driving increases as the ampifier is used in higher gain confi gurations. Capacitive oad driving may be increased by decouping the capacitance from the output with a sma resistance. 4

15 PACKAGE DESCRIPTION N8 Package 8-Lead PDIP (Narrow.3) (LTC DWG # 5-8-5) LT88/LT882.4* (.6) MAX ±.5* (6.477 ±.38) ( ) (.43.65).3 ±.5 (3.32 ±.27).8.5 (.23.38) ( ).65 (.65) TYP. (2.54) BSC NOTE: INCHES. DIMENSIONS ARE MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED. INCH (.254mm).2 (3.48) MIN.8 ±.3 (.457 ±.76).2 (.58) MIN N8 2 5

16 LT88/LT882 PACKAGE DESCRIPTION S8 Package 8-Lead Pastic Sma Outine (Narrow.5) (LTC DWG # 5-8-6).5 BSC.45 ± ( ) NOTE MIN.6 ± ( ).5.57 ( ) NOTE 3.3 ±.5 TYP RECOMMENDED SOLDER PAD LAYOUT ( ) ( ) 8 TYP ( ).4. (..254).6.5 (.46.27) NOTE: INCHES. DIMENSIONS IN (MILLIMETERS).4.9 ( ) TYP 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED.6" (.5mm).5 (.27) BSC SO8 33 6

17 PACKAGE DESCRIPTION S Package 4-Lead Pastic Sma Outine (Narrow.5) (LTC DWG # 5-8-6) LT88/LT882.5 BSC.45 ± ( ) NOTE 3 N MIN 2 3 N/2.6 ± ( ) N N/ ( ) NOTE 3.3 ±.5 TYP RECOMMENDED SOLDER PAD LAYOUT ( ) ( ) 8 TYP ( ).4. (..254).6.5 (.46.27) NOTE: INCHES. DIMENSIONS IN (MILLIMETERS).4.9 ( ) TYP 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED.6" (.5mm).5 (.27) BSC S4 52 Information furnished by Linear Technoogy Corporation is beieved to be accurate and reiabe. However, no responsibiity is assumed for its use. Linear Technoogy Corporation makes no representation that the interconnection of its circuits as described herein wi not infringe on existing patent rights. 7

18 LT88/LT882 TYPICAL APPLICATION 5 C to 6 C Digita Thermometer Operates on 3.3V V CC = 3.3V R 4k R2 4k R F k V CC k.% k.% A /2 LT88 + V CC R T R3 k A2 /2 LT88 + V V = CC +.588/ C 2 μf +IN CLK LTC287 IN D OUT V REF V CC GND CS/SHDN RT: OMEGA F432 Ω RTD R, R2, R3, RF: USE BI k 8 RESISTOR NETWORK 882 TA2 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT2/LT4 Dua/Quad Picoamp Input Op Amps V OS = 6 Max LT67 Gain Programmabe Instrumentation Amp Gain Error =.8% Max LT677 Low Noise, Rai-to-Rai Precision Op Amp e n = 3.2nV/ Hz LT793 Low Noise JFET Op Amp I B = Max LT88 SOT-23 Picoamp Input Precision Op Amp 5 Max V OS, 4 C to 85 C Operation Guaranteed, SOT-23 Package LT884/LT885 Dua/Quad Picoamp Input Op Amps 3 Times Faster than LT88/LT882 LTC25 Zero Drift Op Amp in SOT-23 V OS = 3 Max, Rai-to-Rai Output LTC6/LTC62 Dua/Quad 35μA Rai-to-Rai Output Precision Op Amps Lower Power, Avaiabe in DFN Package LTC68/LTC682 Dua/Quad Precision CMOS Op Amps I B = Max, V OS = 7 Max 8 Linear Technoogy Corporation 63 McCarthy Bvd., Mipitas, CA (48) FAX: (48) LT 89 REV B PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2