LINEAR TECHNOLOGY LT1115 Technical data

FEATURES

■

Voltage Noise: 1.2nV/√Hz Max at 1kHz

0.9nV/√Hz Typ at 1kHz

■

Voltage and Current Noise 100% Tested

■

Gain-Bandwidth Product: 40MHz Min

■

Slew Rate: 10V/µs Min

■

Voltage Gain: 2 Million Min

■

Low THD at 10kHz, AV = –10, RL = 600Ω: 0.002%

VO = 7V

■

Low IMD, CCIF Method, AV = +10: 0.002%

RMS

RL = 600Ω
VO = 7V

RMS

U

APPLICATIO S

LT1115

Ultralow Noise,

Low Distortion, Audio Op Amp

U

DESCRIPTIO

The LT®1115 is the lowest noise audio operational ampli­fier available. This ultralow noise performance (0.9nV/√Hz
at 1kHz) is combined with high slew rates (>15V/µs) and
very low distortion specifications.

The RIAA circuit shown below using the LT1115 has very
low distortion and little deviation from ideal RIAA
response (see graph).

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

■

High Quality Audio Preamplifiers

■

Low Noise Microphone Preamplifiers

■

Very Low Noise Instrumentation Amplifiers

■

Low Noise Frequency Synthesizers

■

Infrared Detector Amplifiers

■

Hydrophone Amplifiers

■

Low Distortion Oscillators

U

TYPICAL APPLICATIO

RIAA Phonograph Preamplifier (40/60db Gain)

18V 18V

COM

+

V

–

V

INPUT

47.5k (MM)

R

IN

100Ω (MC)

COM

18V

+

470µF
35V

+

470µF
35V

–18V

SINGLE
POINT
BOARD
GROUND

C

IN

(SELECT
PER
PHOTO
CART­RIDGE)

22.6Ω

210Ω

+

2200µF
16V

+ +

3

7

+

A1

LT1115

2

–

4

–18V

499Ω

OPEN—MM
CLOSED—MC

4.7µF
FILM

1µF

1µF

35V

35V

100Ω

6

2N4304*
~250Ω
SELECT

2mA

FOR 2mA

1µF

1µF

35V

35V

17.8k

330pF

3900pF

82.5k

BYPASS SUPPLIES WITH LOW ESR CAPS

NOTE:

OTHER CAPS: HIGH QUALITY FILM

R

BOOST

49.9Ω

2

1

4

A2

LT1010CT

+ +

RESISTORS 1%
*OR USE 2mA CURRENT SOURCE
MM = MOVING MAGNET
MC = MOVING COIL

5

3

–18V

210k

15nF

562Ω

25k

R

L

LT1115 • TA01

OUTPUT

3900pF

Measured Deviation from RIAA

Response. lnput at 1kHz = 1mV

Pre-Emphasized

1.0000

VS= ± 18V

0.80000

0.60000

0.40000

0.20000

–0.2000

DEVIATION (dB)

–0.4000

–0.6000

–0.8000

–1.000

=25Ω

R

S

=25°C

T

A

100

FREQUENCY (Hz)

MEASURED

COMPUTER
SIMULATED

1k 10k 50k

0.0

20

RMS

LT1115 • TA02

1115fa

1

LT1115

WWWU

ABSOLUTE AXI U RATI GS

(Note 1)

Supply Voltage ...................................................... ±22V

Differential Input Current (Note 5) ...................... ±25mA

Input Voltage ............................ Equal to Supply Voltage

Output Short-Circuit Duration .......................... Indefinite

U

PACKAGE DESCRIPTIO

Operating Temperature Range ..................... 0°C to 70°C

Storage Temperature Range ..................–65°C to 150°C

Lead Temperature (Soldering, 10 sec).................. 300°C

TOP VIEW

1

2

3

4

5

6

7

8

T

MAX

–

+

SW PACKAGE

16-LEAD PLASTIC SO

= 115°C, θJA = 130°C/W

16

15

14

13

12

11

10

9

NC

NC

TRIM

+

V

OUTPUT

OVERCOMP

NC

NC

ORDER

PART NUMBER

LT1115CSW

LT1115 • POI01

TOP VIEW

V

OS

1

TRIM

–IN

+IN

T

JMAX

–

2

+

3

–

4

V

N PACKAGE

8-LEAD PDIP

= 115°C, θJA = 130°C/W

8

7

6

5

V

OS

TRIM

+

V

OUT
OVER­COMP

ORDER

PART NUMBER

LT1115CN8

TRIM

–IN

+IN

NC

NC

NC

NC

–

V

Consult LTC Marketing for parts specified with wider operating temperature ranges.

ELECTRICAL CHARACTERISTICS

VS = ±18V, TA = 25°C, unless otherwise noted.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

THD Total Harmonic Distortion at 10kHz Av = –10, VO = 7V

IMD Inter-Modulation Distortion (CCIF) Av = 10, VO = 7V

V

OS

I

OS

I

B

e

n

Input Offset Voltage (Note 2) 50 200 µV

Input Offset Current VCM = 0V 30 200 nA

Input Bias Current VCM = 0V ±50 ±380 nA

Input Noise Voltage Density fo = 10Hz 1.0 nV/√Hz

, RL = 600 < 0.002 %

RMS

, RL = 600 < 0.0002 %

RMS

fo = 1000Hz, 100% tested 0.9 1.2 nV/√Hz

Wideband Noise DC to 20kHz 120 nV

RMS

Corresponding Voltage Level –136 dB
re 0.775V

i

n

Input Noise Current Density fo = 10Hz 4.7 pA/√Hz
(Note 3) fo = 1000Hz, 100% tested 1.2 2.2 pA/√Hz

Input Resistance
Common Mode 250 MΩ
Differential Mode 15 kΩ

Input Capacitance 5pF

Input Voltage Range ±13.5 ±15.0 V

2

1115fa

LT1115

ELECTRICAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

CMRR Common Mode Rejection VCM = ±13.5V 104 123 dB

Ratio

PSRR Power Supply Rejection VS = ±4V to ±19V 104 126 dB

Ratio

A

VOL

V

OUT

SR Slew Rate A

GBW Gain-Bandwidth Product fo = 20kHz (Note 4) 40 70 MHz

Z

o

I

S

The

● denotes specifications which apply over the full operating temperature range, otherwise specifications are at T

Large-Signal Voltage Gain RL ≥ 2kΩ, Vo = ±14.5V 2.0 20 V/µV

Maximum Output Voltage No Load ±15.5 ±16.5 V
Swing R

Open Loop 0utput Impedance Vo = 0, Io = 0 70 Ω

Supply Current 8.5 11.5 mA

VS = ±18V, TA = 25°C, unless otherwise noted.

≥ 1kΩ, Vo = ±13V 1.5 15 V/µV

R

L

≥ 600Ω, Vo = ±10V 1.0 10 V/µV

R

L

≥ 2kΩ ±14.5 ±15.5 V

L

≥ 600Ω ±11.0 ±14.5 V

R

L

= –1 10 15 V/µs

VCL

= 25°C.

A

VS = ±18V, unless otherwise noted.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OS

∆VOS/∆TAverage Input Offset Drift 0.5 µV/°C

I

OS

I

B

CMRR Common Mode Rejection V

PSRR Power Supply Rejection VS = ±4.5V to ±18V ● 100 123 dB

A

VOL

V

OUT

I

S

Input Offset Voltage (Note 2) ● 75 280 µV

Input Offset Current VCM = 0V ● 40 300 nA

Input Bias Current VCM = 0V ● ±70 ±550 nA
Input Voltage Range ● ±13 ±14.8 V

= ±13V ● 100 120 dB

Ratio

Ratio

Large-Signal Voltage Gain RL ≥ 2kΩ, Vo = ±13V ● 1.5 15 V/µV

Maximum Output Voltage No Load ±15 ±16.3 V
Swing R

Supply Current ● 9.3 13 mA

CM

RL ≥ 1kΩ, Vo = ±11V 1.0 10 V/µV

≥ 2kΩ ● ±13.8 ±15.3 V

L

R

≥ 600Ω ±10 ±14.3 V

L

Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.

Note 2: Input Offset Voltage measurements are performed by automatic
test equipment approximately 0.5 sec after application of power.

Note 3: Current noise is defined and measured with balanced source
resistors. The resultant voltage noise (after subtracting the resistor noise
on an RMS basis) is divided by the sum of the two source resistors to
obtain current noise.

Note 4: Gain-bandwidth product is not tested. It is guaranteed by design
and by inference from the slew rate measurement.

Note 5: The inputs are protected by back-to-back diodes. Current limiting
resistors are not used in order to achieve low noise. If differential input
voltage exceeds ±1.8V, the input current should be limited to 25mA.

1115fa

3

LT1115

FREQUENCY (Hz)

20

0.001

0.010

0.1

100

1k

20k

TOTAL HARMONIC DISTORTION + NOISE (%)

A

V

= 1000

V

IN

= 20mV

P-P

(7mV

RMS)

V

OUT

= 20V

P-P

(7V

RMS)

T

A

= 25°C

R

L

= 600

V

S

= ±18V

LT1115 • TPC09

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Wideband Noise, DC to 20kHz

0.5µV/DIV

FPO

0.5ms/DIV

THD + Noise vs Frequency
(A

= –10)

V

A
R

V
V

T
V

= –10

V

= 600

L

= 2V

IN
OUT

= 25°C

A

= ±18V

S

= 20V

P-P

(700mV

(7V

P-P

RMS)

RMS)

0.010

Wideband Voltage Noise
(0.1Hz to Frequency Indicated)

10

VS = ± 18V

= 25°C

T

A

1

0.1

RMS VOLTAGE NOISE (µV)

0.01
100

1k

BANDWIDTH (Hz)

10k

100k

THD + Noise vs Frequency
(A

= –100)

V

0.1
A

= –100

V

= 600

R

L

V

0.010

IN

V

OUT

T

A

V

S

= 200mV

= 25°C
= ±18V

= 20V

P-P

P-P

(70mV

(7V

RMS)

RMS)

1M

LT1115 • TPC02

10M

Total Noise vs Matched Source
Resistance

100

R

S

–

R

S

+

10

AT 10Hz

1.0

TOTAL NOISE DENSITY (nV/√Hz)

0.1
3

1

MATCHED SOURCE RESISTANCE, RS (Ω)

30

10

100

300

2 RS NOISE ONLY

THD + Noise vs Frequency
(A

= –1000)

V

0.1
AV = – 1000

= 600

R

L

V

= 20mV

= 20V

P-P
P-P

(7mV
(7V

RMS)

RMS)

0.010

V

T

A

V

IN
OUT

= 25°C
= ±18V

S

AT 1kHz

VS= ± 18V

=25°C

T

A

1k 3k

10k

LT1115 • TPC03

0.001

TOTAL HARMONIC DISTORTION + NOISE (%)

0.0005
20

100 1k

FREQUENCY (Hz)

THD + Noise vs Frequency
(A

= 10)

V

20

A

V

R

V

IN

V

OUT

T

A

V

S

= 10
= 600

L

= 2V

(700mV

P-P

= 20V

P-P

= 25°C
= ±18V

100 1k

(7V

RMS)

FREQUENCY (Hz)

0.010

0.001

TOTAL HARMONIC DISTORTION + NOISE (%)

0.0005

RMS)

LT1115 • TPC04

LT1115 • TPC07

TOTAL HARMONIC DISTORTION + NOISE (%)

0.001

20k

20

100 1k

THD + Noise vs Frequency
(A

= 100)

V

0.1
A

= 100

V

V

= 200mV

IN

V

= 20mV

OUT

T

= 25°C

A

= 600

R

L

= ±18V

V

S

0.010

0.001

TOTAL HARMONIC DISTORTION + NOISE (%)

0.0005
20

20k

100 1k

FREQUENCY (Hz)

(700V

P-P

RMS)

(7V

P-P

RMS)

FREQUENCY (Hz)

20k

LT1115 • TPC05

20k

LT1115 • TPC08

TOTAL HARMONIC DISTORTION + NOISE (%)

0.001
20

100 1k

FREQUENCY (Hz)

THD + Noise vs Frequency
(A

= 1000)

V

20k

LT1115 • TPC06

4

1115fa

TEMPERATURE (°C)

0

0

RMS VOLTAGE NOISE DENSITY (nV/√Hz)

0.8

1.2

30

2.0

0.4

15 75

60

45

1.6

V

S

= ±18V

AT 10Hz

AT 1kHz

LT1115 • TPC15

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LT1115

CCIF IMD Test (Twin Equal
Amplitude Tones at 13 and 14kHz)*

0.1
A

= 10

V

= 600

R

L

= 25°C

T

A

= ±18V

V

S

0.010

0.001

INTERMODULATION DISTORTION (at 1kHz) (%)

0.0001
10m

0.1

OUTPUT AMPLITUDE (V

1

RMS

)

LT1115 • TPC10

10

CCIF IMD Test (Twin Equal
Amplitude Tones at 13 and 14kHz)*

0.1
A

= 10

V

= 10k

R

L

T

= 25°C

A

= ±18V

V

S

0.010

0.001

INTERMODULATION DISTORTION (at 1kHz) (%)

0.0001
10m

0.1

OUTPUT AMPLITUDE (V

Total Noise vs Unmatched Source
Resistance Current Noise Spectrum

100

R

S

10

100

10

Slew Rate, Gain-Bandwidth-Product
vs Overcompensation Capacitor

100

10

SLEW

1

SLEW RATE (V/µs)

C

FROM PIN 5 TO PIN 6

OC

= ±18V

V

S

= 25°C

T

A

0.1
1 100

1

RMS

10

)

LT1115 • TPC11

10

OVERCOMPENSATION CAPACITOR (pF)

1000

GWB

LT1115 • TPC12

10000

10000

GAIN AT 20kHz

1000

100

10

Voltage Noise vs Temperature

AT 10Hz

1.0

TOTAL NOISE DENSITY (nV/√Hz)

0.1
1

3

UNMATCHED SOURCE RESISTANCE, RS (Ω)

30

10

100

AT 1kHz

RS NOISE ONLY

V

= ± 18V

S

T

= 25°C

A

1k 3k

300

10k

LT1115 • TPC13

CURRENT NOISE DENSITY (pA/√Hz)

0.1

1

10

TYPICAL

1/f CORNER = 250Hz

100

FREQUENCY (Hz)

Voltage Noise vs Supply Voltage Supply Current vs Temperature

RMS VOLTAGE NOISE DENSITY (nV/√Hz)

1.25

0.75

1.5

1.0

0.5

T

0

= 25°C

A

AT 1kHz

± 5

± 10

SUPPLY VOLTAGE (V)

± 15

±20

LT1115 • TPC16

10

9

8

7

6

5

4

3

SUPPLY CURRENT (mA)

2

1

0

0

V

S

V

S

V

15

TEMPERATURE (°C)

= ±18V

= ±15V

= ±5V

S

30

45

1k

10k

LT1115 • TPC14

Output Short-Circuit Current
vs Time

60

LT1115 • TPC17

50

40

30

20

10

0

–10

–20

–30

SHORT-CIRCUIT CURRENT (mA)

SINKING SOURCING

–40

75

–50

01

TIME FROM OUTPUT SHORT TO GROUND (MINUTES)

VS = ± 18V

25°C

25°C

23

LT1115 • TPC18

*See CCIF Test Note at end of “Typical Performance Characteristics”.

1115fa

5