Datasheet

ManualsBrandsLINEAR TECHNOLOGY ManualsLinear ICsLinear IC - Op-amp Scrambler (zero drift) SO 16

LTC1051/LTC1053

10513fa

FREQUENCY (Hz)

VOLTAGE NOISE DENSITY (nV√Hz)

120

100

100 1k 10k

1051/53 TA01b

The LTC

1051/LTC1053 are high performance, low cost

dual/quad zero-drift operational amplifiers. The unique

achievement of the LTC1051/LTC1053 is that they integrate

on chip the sample-and-hold capacitors usually required

externally by other chopper amplifiers. Further, the

LTC1051/LTC1053 offer better combined overall DC and

AC performance than is available from other chopper

stabilized amplifiers with or without internal sample/hold

capacitors.

The LTC1051/LTC1053 have an offset voltage of 0.5µV,

drift of 0.01µV/°C, DC to 10Hz, input noise voltage typically

1.5µV

P-P

and typical voltage gain of 140dB. The slew rate

of 4V/µs and gain bandwidth product of 2.5MHz are

achieved with only 1mA of supply current per op amp.

Overload recover times from positive and negative

saturation conditions are 1.5ms and 3ms respectively,

about a 100 or more times improvement over chopper

amplifiers using external capacitors.

The LTC1051 is available in an 8-lead standard plastic

dual-in-line package as well as a 16-pin SW package. The

LTC1053 is available in a standard 14-pin plastic package

and an 18-pin SO. The LTC1051/LTC1053 are plug in

replacements for most standard dual/quad op amps with

improved performance.

■

Thermocouple Amplifiers

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Electronic Scales

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Medical Instrumentation

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Strain Gauge Amplifiers

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High Resolution Data Acquisition

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DC Accurate R C Active Filters

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Dual/Quad Low Cost Precision Op Amp

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No External Components Required

■

Maximum Offset Voltage: 5µV

■

Maximum Offset Voltage Drift: 0.05µV/°C

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Low Noise 1.5µV

P-P

(0.1Hz to 10Hz)

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Minimum Voltage Gain: 120dB

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Minimum PSRR: 120dB

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Minimum CMRR: 114dB

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Low Supply Current: 1mA/Op Amp

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Single Supply Operation: 4.75V to 16V

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Input Common Mode Range Includes Ground

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Output Swings to Ground

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Typical Overload Recovery Time: 3ms

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Pin Compatible with Industry Standard Dual and

Quad Op Amps

Dual/Quad Precision

Zero-Drift Operational Amplifiers

With Internal Capacitors

High Performance Low Cost Instrumentation Amplifier LTC1051 Noise Spectrum

–

1/2

LTC1051

1/2

LTC1051

–5V

1051/53 TA01a

R1 = 499Ω, 0.1%

R2 = 100k, 0.1%

GAIN = 201

MEASURED CMRR ~ 120dB AT DC

MEASURED INPUT V

3µV

MEASURED INPUT NOISE 2µV

P-P

(DC – 10Hz)

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

, LTC and LT are registered trademarks of Linear Technology Corporation.

APPLICATIO S

Summary of content (16 pages)

PAGE 1
LTC1051/LTC1053 Dual/Quad Precision Zero-Drift Operational Amplifiers With Internal Capacitors DESCRIPTIO U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Dual/Quad Low Cost Precision Op Amp No External Components Required Maximum Offset Voltage: 5µV Maximum Offset Voltage Drift: 0.05µV/°C Low Noise 1.5µVP-P (0.1Hz to 10Hz) Minimum Voltage Gain: 120dB Minimum PSRR: 120dB Minimum CMRR: 114dB Low Supply Current: 1mA/Op Amp Single Supply Operation: 4.
PAGE 2
LTC1051/LTC1053 W W W AXI U U ABSOLUTE RATI GS (Note 1) Total Supply Voltage (V + to V –) ............................ 16.5V Input Voltage ........................ (V + + 0.3V) to (V – – 0.3V) Output Short-Circuit Duration .......................... Indefinite Operating Temperature Range LTC1051M, LTC1051AM (OBSOLETE) .. –55°C to 125°C LTC1051C/LTC1053C ......................... – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec)...........
PAGE 3
LTC1051/LTC1053 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±5V unless otherwise noted. PARAMETER CONDITIONS Input Noise Current f = 10Hz Common Mode Rejection Ratio, CMRR VCM = V– LTC1051/LTC1053 MIN TYP MAX MIN 2.2 to 2.7V ● 106 100 130 114 110 LTC1051A TYP MAX UNITS 2.2 fA/√Hz 130 dB dB Differential CMRR LTC1051, LTC1053 (Note 3) VCM = V – to 2.
PAGE 4
LTC1051/LTC1053 U W TYPICAL PERFOR A CE CHARACTERISTICS Common Mode Input Range vs Supply Voltage Sampling Frequency vs Supply Voltage 4.0 SAMPLING FREQUENCY, fS (kHz) COMMON MODE RANGE (V) 6 4 2 0 –2 VCM = V – –4 TA = 25°C 5 SAMPLING FREQUENCY, fS (kHz) 8 Sampling Frequency vs Temperature 3.5 3.0 2.5 –6 0 1 2 3 4 5 6 SUPPLY VOLTAGE (±V) 7 2.0 8 4 14 16 6 8 10 12 TOTAL SUPPLY VOLTAGE, V + TO V – (V) 2 –50 1.50 TA = 25°C 0.25 1.
PAGE 5
LTC1051/LTC1053 U W TYPICAL PERFOR A CE CHARACTERISTICS Small Signal Transient Response Overload Recovery Large Signal Transient Response 400mV INPUT 0 OUTPUT 50mV /DIV OUTPUT 2V/DIV INPUT 100mV INPUT 6V 0 OUTPUT – 5V 2µs/DIV AV = 1, RL = 10k, CL = 100pF VS = ±5V, TA = 25°C 0.5ms AV = –100 VS = ±5V 1051/53 G10 2µs/DIV AV = 1, RL = 10k, CL = 100pF VS = ±5V, TA = 25°C 1051/53 G11 1051/53 G12 LTC1051/LTC1053 DC to 10Hz Noise VS = ±5V TA = 25°C 1.
PAGE 6
LTC1051/LTC1053 U W U U APPLICATIO S I FOR ATIO ACHIEVING PICOAMPERE/MICROVOLT PERFORMANCE Picoamperes In order to realize the picoampere level of accuracy of the LTC1051/LTC1053, proper care must be exercised. Leakage currents in circuitry external to the amplifier can significantly degrade performance. High quality insulation should be used (e.g.
PAGE 7
LTC1051/LTC1053 U W U U APPLICATIO S I FOR ATIO RS = 0, AV =11V/V 20mV/DIV R2 100k RS = 100k, AV =11V/V 20mV/DIV RS = 0, AV =101V/V 20mV/DIV R1 1k – 1/2 LTC1051 RS RS = 100k, AV =101V/V 20mV/DIV 100µs/DIV 100µs/DIV (a) (b) + 1051/53 F02 (c) Figure 2. Clock Feedthrough The charge injection at the op amp input pins will cause small output spikes. This phenomenon is often referred to as “clock feedthrough” and can be easily observed when the closed-loop gain exceeds 10V/V (Figure 2).
PAGE 8
LTC1051/LTC1053 U W U U APPLICATIO S I FOR ATIO LTC1051/LTC1053 as AC Amplifiers Aliasing Although initially chopper stabilized op amps were designed to minimize DC offsets and offset drifts, the LTC1051/LTC1053 family, on top of its outstanding DC characteristics, presents efficient AC performance. For instance, at single 5V supply, each op amp typically consumes 0.5mA and still provides 1.8MHz gain bandwidth product and 3V/µs slew rate.
PAGE 9
LTC1051/LTC1053 U W U U APPLICATIO S I FOR ATIO 2. If we arbitrarily accept that “aliasing” occurs when output alias signals reach an amplitude of 0.01% or more of the output signal, then: the approximate minimum frequency of an AC input signal which will cause aliasing is equal to the internal clock frequency multiplied by the square root of the op amp feedback factor. For instance, with closed-loop gain of –10, the feedback factor is 1/11 and if fCLK = 2.
PAGE 10
LTC1051/LTC1053 U W U U APPLICATIO S I FOR ATIO 5. For unity-gain inverting configuration, all the alias frequencies are 80dB to 84dB down from the output signal (Figures 6a, 6b). Combined with excellent THD under wide swing, the LTC1051/LTC1053 op amps make efficient unity gain inverters. For gain higher than –1, the “signal to alias” ratio decreases at an approximate rate of –6dB per decade of closed-loop gain (Figure 9). 6.
PAGE 11
LTC1051/LTC1053 U TYPICAL APPLICATIO S Obtaining Ultralow VOS Drift and Low Noise The dual chopper op amp buffers the inputs of A1 and corrects its offset voltage and offset voltage drift. With the R, C values shown, the power-up warm up time is typically 20 seconds. The step response of the composite amplifier does not present settling tails. The LT1007 should be used when extremely low noise; VOS and VOS drift are sought when the input source resistance is low—for instance a 350Ω strain gauge bridge.
PAGE 12
LTC1051/LTC1053 U TYPICAL APPLICATIO S Paralleling Choppers to Improve Noise NOTE: THIS CIRCUIT CAN ALSO BE USED AS A DIFFERENCE AMPLIFIER FOR STRAIN GAUGES. CONNECT R2/3 AND R1/3 FROM NONINVERTING INPUTS, SHORTED TOGETHER, TO GROUND AND TO SOURCE RESPECTIVELY. R2 R1 VIN 2 3 Differential Voltage to Current Converter – 1/4 LTC1053 R 1 0.1µF 3 V1 R + 2 + 1 1/4 LTC1053 20k – 5V 5V 10k 10k 10k R2 0.
PAGE 13
LTC1051/LTC1053 U TYPICAL APPLICATIO S Dual Instrumentation Amplifier + Six Decade Log Amplifier 5V LTC1043 3 8 7 1µF 2 11 5V Q1 Q1 0.1µF 3k 0.1% 2 1nA < IIN <1mA 3 – 1/2 LTC1051 1 15.8k 0.1% 2M 8 7 1/2 LTC1051 1N4148 4 1k 13 14 6 5 0.22µF + LT1009 1k 0.1% VOUT = LOG VIN –2V –5V 0.1µF VOUT1 – 100k – 5V 5 1 1µF 5 1µF + 8 1/2 LTC1051 12 2.5V 2.5M 0.1% 6 – VIN 10k 0.1% INPUT 1 22pF + 0.
PAGE 14
LTC1051/LTC1053 U PACKAGE DESCRIPTIO J Package 8-Lead CERDIP (Narrow 0.300, Hermetic) (LTC DWG # 05-08-1110) .300 BSC (7.62 BSC) CORNER LEADS OPTION (4 PLCS) .008 – .018 (0.203 – 0.457) 0° – 15° .015 – .060 (0.381 – 1.524) .023 – .045 (0.584 – 1.143) HALF LEAD OPTION .045 – .068 (1.143 – 1.650) FULL LEAD OPTION .405 (10.287) MAX .005 (0.127) MIN .200 (5.080) MAX 8 NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS .014 – .026 (0.360 – 0.660) 5 .025 (0.635) RAD TYP .220 – .
PAGE 15
LTC1051/LTC1053 U PACKAGE DESCRIPTIO SW Package 16-Lead Plastic Small Outline (Wide 0.300) (LTC DWG # 05-08-1620) .050 BSC .045 ±.005 .030 ±.005 TYP .398 – .413 (10.109 – 10.490) NOTE 4 15 16 N 14 12 13 10 11 9 N .325 ±.005 .420 MIN .394 – .419 (10.007 – 10.643) NOTE 3 1 2 3 NOTE: 1. DIMENSIONS IN N/2 N/2 INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. PIN 1 IDENT, NOTCH ON TOP AND CAVITIES ON THE BOTTOM OF PACKAGES ARE THE MANUFACTURING OPTIONS.
PAGE 16
LTC1051/LTC1053 U TYPICAL APPLICATIO S DC Accurate, 3rd Order, 100Hz, Butterworth Antialiasing Filter Dynamic Range 8V R1 16.5k R2 118k R3 21k C 0.1µF C2 0.1µF 2 3 THD + NOISE (%) C1 0.1µF VIN 0.1µF + 1/2 LTC1051 – 1 VOUT 0.01 R2A 10k 0.0001 0.1 1051/53 AC09 – 1/2 LTC1051 CA 0.22µF Dynamic Range + 60dB 0.1 C1B 0.0022µF R1B 50k THD + NOISE (%) C1A 0.022µF R3B 412k – 1/2 LTC1051 CB 0.022µF 120dB 5.0 1.0 VIN (VRMS), fIN = 30Hz 1051/53 AC08 R2B 50k R3A 26.