LT1637_技术文档

LT1637

1.1MHz, 0.4V/µs

Over-The-Top Micropower, Rail-To-Rail

Input and Output Op Amp

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DESCRIPTIO

FEATURES

Operates with Inputs Above V⁺

TheLT^®1637isaruggedopampthatoperatesonallsingle

and split supplies with a total voltage of 2.7V to 44V. The

■

Rail-to-Rail Input and Output

■

Micropower: 250µA Supply Current Max

Gain-Bandwidth Product: 1.1MHz

Slew Rate: 0.4V/µs

LT1637 has a gain-bandwidth product of 1.1MHz while

drawinglessthan250µAofquiescentcurrent.TheLT1637

can be shut down, making the output high impedance and

reducing the quiescent current to only 3µA. The LT1637 is

reverse supply protected: it draws virtually no current for

reverse supply up to 25V. The input range of the LT1637

includes both supplies and the output swings to both

supplies. Unlike most micropower op amps, the LT1637

can drive heavy loads; its rail-to-rail output drives 25mA.

TheLT1637isunity-gainstableintoallcapacitiveloadsup

to 4700pF when optional 0.22µF and 150Ω compensation

is used.

■

Low Input Offset Voltage: 350µV Max

Single Supply Input Range: –0.4V to 44V

High Output Current: 25mA Min

Specified on 3V, 5V and ±15V Supplies

Output Shutdown

Output Drives 4700pF with Output Compensation

Reverse Battery Protection to 25V

High Voltage Gain: 800V/mV

High CMRR: 110dB

The LT1637 has a unique input stage that operates and

remains high impedance when above the positive supply.

The inputs take 44V both differential and common mode,

even when operating on a 3V supply. Built-in resistors

protect the inputs for faults below the negative supply up

to 22V. There is no phase reversal of the output for inputs

5V below V_EEor 44V above V_EE, independent of V_CC.

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APPLICATIO S

■

Battery or Solar Powered Systems:

Portable Instrumentation

Sensor Conditioning

Supply Current Sensing

Battery Monitoring

■

The LT1637 op amp is available in the 8-pin MSOP, PDIP

and SO packages.

■

MUX Amplifiers

■

4mA to 25mA Transmitters

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

Over-The-Top is a trademark of Linear Technology Corporation.

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TYPICAL APPLICATIO

Over-The-Top^TMCurrent Source with Shutdown

Switchable Precision Current Source

Current Source Timing

4V TO 44V

6V

4V

2V

0V

+

4.7µF

R*

LT1004-1.2

2k

R

V_SHDN

+

–

LT1637

TP0610

1.2

R

I

=

OUT

10mA

5mA

0mA

I

e.g., 10mA = 120Ω

OUT

I_OUT

SHDN

*OPTIONAL FOR LOW OUTPUT CURRENTS,

R* = R

1637 TA01

100µs/DIV

1637 TA01b

1

LT1637

W W

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ABSOLUTE AXI U RATI GS

(Note 1)

Total Supply Voltage (V⁺to V^–) .............................. 44V

Input Differential Voltage ......................................... 44V

Input Current ...................................................... ±25mA

Shutdown Pin Voltage Above V^–..................................... 32V

Shutdown Pin Current ........................................ ±10mA

Output Short-Circuit Duration (Note 2).........Continuous

Operating Temperature Range (Note 3) .. –40°C to 85°C

Specified Temperature Range (Note 4)... –40°C to 85°C

Junction Temperature........................................... 150°C

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

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

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W

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PACKAGE/ORDER I FOR ATIO

TOP VIEW

ORDER PART

NUMBER

ORDER PART

TOP VIEW

NUMBER

NULL

1

2

3

4

8

7

6

5

NULL

1

2

3

4

8 NULL

7 V

6 OUT

5 SHDN

–

+

–

+

IN

V

IN

+

LT1637CMS8

LT1637CN8

LT1637CS8

LT1637IN8

LT1637IS8

IN

+

IN

OUT

–

V

–

V

SHDN

MS8 PACKAGE

8-LEAD PLASTIC MSOP

N8 PACKAGE

8-LEAD PDIP

S8 PACKAGE

8-LEAD PLASTIC SO

T_JMAX= 150°C, θ_JA= 250°C/W

T_JMAX= 150°C, θ_JA= 130°C/W (N8)

T_JMAX= 150°C, θ_JA= 190°C/W (S8)

MS8 PART

MARKING

S8 PART

MARKING

LTIE

1637

1637I

Consult factory for Military grade parts.

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3V A D 5V ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the specified temperature range, otherwise specifications are at T_A= 25°C.

V_S= 3V, 0V; V_S= 5V, 0V; V_SHDN= V^–,V_CM= V_OUT= Half Supply unless otherwise specified. (Note 4)

SYMBOL PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

V

Input Offset Voltage

N8, S8 Packages

100

350

550

700

µV

OS

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

MS8 Package

100

350

750

900

µV

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

Input Offset Voltage Drift (Note 9)

Input Offset Current

N8, S8 Packages, –40°C ≤ T ≤ 85°C

●

1

2

3

6

µV/°C

A

MS8 Package, –40°C ≤ T ≤ 85°C

A

I

●

0.4

6.0

2.5

nA

µA

OS

V

= 44V (Note 5)

CM

Input Bias Current

●

20

23

0.1

50

60

nA

µA

nA

B

CM

V = 0V

S

Input Noise Voltage

0.1Hz to 10Hz

f = 1kHz

0.6

27

µV

P-P

e

Input Noise Voltage Density

Input Noise Current Density

nV/√Hz

pA/√Hz

n

i

f = 1kHz

0.08

n

2

LT1637

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3V A D 5V ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the specified temperature range, otherwise specifications are at T_A= 25°C.

V_S= 3V, 0V; V_S= 5V, 0V; V_SHDN= V^–, V_CM= V_OUT= Half Supply unless otherwise specified. (Note 4)

SYMBOL PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

R

IN

Input Resistance

Differential

Common Mode, V = 0V to 44V

1

0.7

2.6

1.4

MΩ

CM

C

Input Capacitance

4

pF

V

IN

Input Voltage Range

●

0

44

CMRR

Common Mode Rejection Ratio

(Note 5)

V

= 0V to (V – 1V)

= 0V to 44V (Note 8)

●

88

80

110

98

dB

CM

CC

A

Large-Signal Voltage Gain

V = 3V, V = 500mV to 2.5V, R = 10k

150

100

75

400

V/mV

VOL

S

O

L

V = 3V, 0°C ≤ T ≤ 70°C

●

S

A

V = 3V, –40°C ≤ T ≤ 85°C

S

A

V = 5V, V = 500mV to 4.5V, R = 10k

300

200

150

800

V/mV

S

O

L

V = 5V, 0°C ≤ T ≤ 70°C

●

S

A

V = 5V, –40°C ≤ T ≤ 85°C

S

A

V

Output Voltage Swing LOW

Output Voltage Swing HIGH

No Load

●

3

325

580

8

mV

OL

OH

I

= 5mA

700

1300

SINK

V = 5V, I

S

= 10mA

SINK

V = 3V, No Load

●

2.94

2.25

2.975

2.67

V

S

V = 3V, I

S

= 5mA

SOURCE

V = 5V, No Load

●

4.94

3.80

4.975

4.45

V

S

V = 5V, I

= 10mA

S

SOURCE

I

Short-Circuit Current (Note 2)

V = 3V, Short Output to Ground

10

15

14

45

mA

SC

S

V = 3V, Short Output to V

S

CC

V = 5V, Short Output to Ground

15

22

60

mA

S

V = 5V, Short Output to V

S

CC

PSRR

Power Supply Rejection Ratio

Minimum Supply Voltage

Reverse Supply Voltage

V = 3V to 12.5V, V = V = 1V

●

90

98

dB

V

S

CM

O

2.7

I = –100µA

S

25

40

V

I

Supply Current

(Note 6)

190

250

295

µA

S

●

Supply Current, SHDN

Shutdown Pin Current

V

= 2V, No Load (Note 6)

3

12

µA

PIN5

V

= 0.3V, No Load (Note 6)

= 2V, No Load (Note 5)

= 3.3V

●

0.2

1.0

2.5

4.3

15

5

nA

µA

SHDN

PIN5

= 5V

Output Leakage Current

Maximum Shutdown Pin Current

Turn-On Time

V

= 2V, No Load (Note 6)

= 32V, No Load (Note 5)

●

0.02

20

1

µA

µs

PIN5

150

t

= 5V to 0V, R = 10k

45

ON

L

Turn-Off Time

= 0V to 5V, R = 10k

3

OFF

L

Settling Time

0.1% A = 1, ∆V = 2V

9

SETTLING

V

O

GBW

Gain-Bandwidth Product

(Note 5)

f = 10kHz

650

550

500

1000

kHz

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

SR

Slew Rate

(Note 7)

A = –1, R = ∞

0.210

0.185

0.170

0.35

V/µs

V

L

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

3

LT1637

±15V ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the specified temperature range, otherwise specifications are at T_A= 25°C.

V_S= ±15V, V_CM= 0V, V_OUT= 0V, V_SHDN= V^–unless otherwise specified. (Note 4)

SYMBOL PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

V

Input Offset Voltage

N8, S8 Packages

100

450

650

800

µV

OS

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

MS8 Package

100

450

800

950

µV

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

Input Offset Voltage Drift (Note 9)

N8, S8 Packages, –40°C ≤ T ≤ 85°C

●

1

2

3

6

µV/°C

A

MS8 Package, –40°C ≤ T ≤ 85°C

A

I

Input Offset Current

Input Bias Current

●

1

17

6

nA

OS

50

B

Input Noise Voltage

0.1Hz to 10Hz

f = 1kHz

0.6

27

µV

P-P

e

Input Noise Voltage Density

Input Noise Current Density

Input Resistance

nV/√Hz

pA/√Hz

n

i

f = 1kHz

0.08

n

R

IN

Differential

Common Mode, V = –15V to 14V

1

3

2200

MΩ

CM

C

Input Capacitance

4

pF

V

IN

Input Voltage Range

●

–15

80

29

CMRR

Common Mode Rejection Ratio

Large-Signal Voltage Gain

V

= –15V to 29V

110

400

dB

CM

A

V

V = ±14V, R = 10k

0°C ≤ T ≤ 70°C

–40°C ≤ T ≤ 85°C

100

75

50

V/mV

VOL

O

L

●

A

Output Voltage Swing LOW

Output Voltage Swing HIGH

Short-Circuit Current (Note 2)

No Load

●

–14.997 –14.95

–14.680 –14.25

–14.420 –13.65

V

OL

I

= 5mA

= 10mA

SINK

No Load

●

14.9

14.2

13.7

14.967

14.667

14.440

V

OH

I

= 5mA

= 10mA

SOURCE

I

Short Output to GND

0°C ≤ T ≤ 70°C

–40°C ≤ T ≤ 85°C

±25

±20

±15

±31.7

mA

SC

●

A

PSRR

Power Supply Rejection Ratio

Minimum Supply Voltage

Supply Current

V = ±1.5V to ±22V

●

90

115

dB

V

S

±1.35

I

230

6

300

370

µA

S

●

Positive Supply Current, SHDN

Shutdown Pin Current

V

= –20V, V = ±22V, No Load

40

µA

PIN5

S

V

= –21.7V, V = ±22V, No Load

●

0.3

0.9

15

8

nA

µA

SHDN

PIN5

S

= –20V, V = ±22V, No Load

S

Maximum Shutdown Pin Current

Output Leakage Current

Shutdown Pin Input Low Voltage

Shutdown Pin Input High Voltage

Turn-On Time

V

= 32V, V = ±22V

●

20

0.02

–21.6

–20.8

35

150

2

µA

V

PIN5

S

= –20V, V = ±22V, No Load

S

V

V = ±22V

–21.7

L

S

V = ±22V

–20.0

V

H

S

t

V

= –10V to –15V, R = 10k

µs

ON

OFF

PIN5

L

Turn-Off Time

= –15V to –10V, R = 10k

3

L

4

LT1637

±15V ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the specified temperature range, otherwise specifications are at T_A= 25°C.

V_S= ±15V, V_CM= 0V, V_OUT= 0V, V_SHDN= V^–unless otherwise specified. (Note 4)

SYMBOL PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

GBW

SR

Gain-Bandwidth Product

f = 10kHz

750

650

600

1100

kHz

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

Slew Rate

A = –1, R = ∞, V = ±10V, Measure at V = ±5V

0.225

0.200

0.180

0.4

V/µs

V

L

O

0°C ≤ T ≤ 70°C

●

A

–40°C ≤ T ≤ 85°C

A

Note 1: Absolute Maximum Ratings are those values beyond which the life

of a device may be impaired.

Note 5: V = 5V limits are guaranteed by correlation to V = 3V and

S S

V = ±15V or V = ±22V tests.

S S

Note 2: A heat sink may be required to keep the junction temperature

below absolute maximum.

Note 6: V = 3V limits are guaranteed by correlation to V = 5V and

S S

V = ±15V or V = ±22V tests.

S S

Note 3: The LT1637 is guaranteed functional over the operating

temperature range of –40°C to 85°C.

Note 7: Guaranteed by correlation to slew rate at V = ±15V and GBW at

S

V = 3V and V = ±15V tests.

S

Note 4: The LT1637C is guaranteed to meet specified performance from

0°C to 70°C. The LT1637C is designed, characterized and expected to

meet specified performance from –40°C to 85°C but is not tested or QA

sampled at these temperatures. The LT1637I is guaranteed to meet

specified performance from –40°C to 85°C.

Note 8: This specification implies a typical input offset voltage of 650µV at

= 44V and a maximum input offset voltage of 5.4mV at V = 44V.

Note 9: This parameter is not 100% tested.

V

CM

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TYPICAL PERFOR A CE CHARACTERISTICS

Input Bias Current

vs Common Mode Voltage

Supply Current vs Supply Voltage

Minimum Supply Voltage

40

30

400

350

300

250

200

150

100

50

400

300

V

= 5V, 0V

S

20

200

10

T

= 125°C

100

A

T

= –55°C

A

0.12

0.08

0.04

0

T

A

= 125°C

T

= 25°C

A

–100

–200

–300

–400

T

= 125°C

= –55°C

A

T

= –55°C

= 25°C

3

A

T

= 25°C

A

0.04

0.08

0

10

20

30

40

0

1

2

4

5

4

4.2 4.4 4.6 4.8

5

10 20 30 40 50

TOTAL SUPPLY VOLTAGE (V)

COMMON MODE VOLTAGE (V)

1637 G01

1637 G02

1637 G03

5

LT1637

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TYPICAL PERFOR A CE CHARACTERISTICS

Output Saturation Voltage

vs Load Current (Output Low)

Output Saturation Voltage

vs Input Overdrive

Output Saturation Voltage

vs Load Current (Output High)

1

10

1

100

90

80

70

60

50

40

30

20

10

0

V

= 5V, 0V

= 30mV

V

= 5V, 0V

= 30mV

S

OD

V = 5V, 0V

S

NO LOAD

S

OD

0.1

T

= 125°C

A

T

= 125°C

A

T

= 25°C

A

T

= 25°C

A

0.01

OUTPUT HIGH

OUTPUT LOW

T

= –55°C

A

T

= –55°C

A

0.01

0.001

0.0001 0.001 0.01

0.1

1

10

100

0.0001 0.001 0.01

0.1

1

10

100

0

10 20 30 40 50 60 70 80 90 100

INPUT OVERDRIVE (mV)

1637 G06

SOURCING LOAD CURRENT (mA)

SINKING LOAD CURRENT (mA)

1637 G04

1637 G05

Noise Voltage Density

vs Frequency

0.1Hz to 10Hz Noise Voltage

Input Noise Current vs Frequency

70

60

50

40

30

20

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0

V

= ±15V

V

= ±2.5V

V

= ±15V

S

1

10

100

1000

0

1

2

3

4

5

6

7

8

9

10

1

10

100

1000

FREQUENCY (Hz)

TIME (s)

FREQUENCY (Hz)

1637 G09

1637 G08

1637 G07

Open-Loop Gain and Phase Shift

vs Frequency

Gain-Bandwidth Product

vs Temperature

Slew Rate vs Temperature

70

60

50

40

120

100

80

1300

1200

1100

1000

900

0.7

0.6

0.5

0.4

0.3

0.2

0.1

V

= ±2.5V

S

RISING, V = ±15V

S

PHASE

60

V

= ±15V

S

RISING, V = ±1.5V

S

30

20

40

20

GAIN

FALLING, V = ±15V

S

V

= ±1.5V

S

10

0

FALLING, V = ±1.5V

S

–10

–20

–30

800

700

1k

10k

100k

1M

–50

25

50

75

100 125

–50 –25

0

25

50

75 100 125

–25

0

FREQUENCY (Hz)

TEMPERATURE (°C)

1637 G10

1637 G11

1637 G12

6

LT1637

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TYPICAL PERFOR A CE CHARACTERISTICS

Gain-Bandwidth Product and

Phase Margin vs Supply Voltage

CMRR vs Frequency

PSRR vs Frequency

100

90

80

70

60

50

40

30

20

10

0

90

80

70

60

50

40

30

20

10

0

1300

1250

1200

1150

1100

1050

1000

55

50

45

40

35

30

25

V

= ±2.5V

S

V

= ±15V

PHASE MARGIN

S

POSITIVE SUPPLY

V

= ±1.5V

S

GAIN BANDWIDTH

NEGATIVE SUPPLY

–10

1k

10k

100k

FREQUENCY (Hz)

1M

1k

10k

100k

FREQUENCY (Hz)

1M

0

5

10 15 20 25 30 35 40 45

TOTAL SUPPLY VOLTAGE (V)

1637 G14

1637 G15

1637 G13

Gain-Bandwidth Product and

Phase Margin vs Load Resistance

Undistorted Output Swing

vs Frequency

Output Impedance vs Frequency

10k

1k

1400

1300

1200

1100

1000

900

50

45

40

35

30

25

20

15

10

35

30

25

20

15

10

5

DISTORTION ≤ 1%

= 1

V

= ±2.5V

V = ±2.5V

S

V = ±15V

s

A

V

PHASE MARGIN

A

= 100

= 10

= 1

V

100

10

GAIN BANDWIDTH

A

V

800

1

V = ±2.5V

s

A

V

700

0.1

100

0

100

600

1k

10k

LOAD RESISTANCE (Ω)

100k

1k

10k

100k

1M

1k

10k

100k

FREQUENCY (Hz)

1637 G17

1637 G18

1637 G16

Capacitive Load Handling,

Overshoot vs Capacitive Load

Settling Time to 0.1%

vs Output Step

Total Harmonic Distortion + Noise

vs Frequency

10

8

100

90

10

1

V

S

= ±15V

V

= ±2.5V

V

= 3V, 0V

S

NO OUTPUT COMPENSATION

= 1.8V

OUT

= 1.2V

P-P

6

80

CM

A

V

= –1

A

V

= 1

A

= 2

V

R

L

=10k

4

70

A

= 1

A

V

= 5

V

2

60

50

0.1

0

A

= 10

V

–2

–4

–6

–8

–10

40

30

20

10

0

0.01

0.001

0.0001

A

= –1

= 1

V

A

= 1

A = –1

V

A

V

0

20

SETTLING TIME (µs)

30

10

40

10

100

1000

10000

10

100

1k

FREQUENCY (Hz)

10k

100k

CAPACITIVE LOAD (pF)

1637 G20

1637 G21

1637 G19

7

LT1637

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TYPICAL PERFOR A CE CHARACTERISTICS

Total Harmonic Distortion + Noise

vs Load Resistance

Total Harmonic Distortion + Noise

vs Output Voltage

10

1

R

V

= 10k

CM

f = 1kHz

V

A

V

= 3V TOTAL

= 1

L

S

V

= HALF SUPPLY

A

V

= 1

= 3V, 0V

V

S

= 1.8V AT 1kHz

V

= ±1.5V

= ±0.9V

IN

P-P

S

IN

FOR A = –1, R = 100k

V

G

0.1

0.01

A

V

S

= –1

= ±1.5V

A

V

= 1

= ±1.5V

V

S

V

= 3V, 0V

S

= 0.6V TO 2.4V

IN

0.1

A

V

= 1

= 3V, 0V

V

S

0.001

0.01

0.001

V

= 3V, 0V

IN

S

= 0.3V TO 2.1V

A

= –1, V = 3V, 0V

S

V

0.0001

0

1

2

3

100

1k

10k

100k

LOAD RESISTANCE TO GROUND (Ω)

OUTPUT VOLTAGE (V

)

P-P

1637 G23

1637 G22

Open-Loop Gain

Large-Signal Response

Small-Signal Response

V_S= ±15V

A_V= 1

V_S= ±15V

A

_V= –1

10V

A

B

50mV

B

C

–50mV

A: R_L= 2k

B: R_L= 10k

C: R_L= 50k

–10V

0V

10V

1637 G24

1637 G25

1637 G26

OUTPUT VOLTAGE (5V/DIV)

U

W U U

APPLICATIO S I FOR ATIO

Supply Voltage

Inputs

The positive supply pin of the LT1637 should be bypassed

with a small capacitor (about 0.01µF) within an inch of the

pin. When driving heavy loads an additional 4.7µF electro-

lytic capacitor should be used. When using split supplies,

the same is true for the negative supply pin.

The LT1637 has two input stages, NPN and PNP (see the

Simplified Schematic), resulting in three distinct operat-

ingregionsasshownintheInputBiasCurrentvsCommon

Mode typical performance curve.

For input voltages about 0.9V or more below V⁺, the PNP

input stage is active and the input bias current is typically

–20nA. When the input voltage is about 0.5V or less from

V⁺, the NPN input stage is operating and the input bias

current is typically 80nA. Increases in temperature will

cause the voltage at which operation switches from the

PNPstagetotheNPNstagetomovetowardsV⁺. Theinput

offset voltage of the NPN stage is untrimmed and is

typically 600µV.

The LT1637 is protected against reverse battery voltages

up to 25V. In the event a reverse battery condition occurs,

the supply current is typically less than 1nA.

When operating the LT1637 on total supplies of 30V or

more, the supply must not be brought up faster than 1µs.

This is especially true if low ESR bypass capacitors are

used. A series RLC circuit is formed from the supply lead

inductance and the bypass capacitor. 5Ω of resistance in

the supply or the bypass capacitor will dampen the tuned

circuit enough to limit the rise time.

8

LT1637

U

W

U U

APPLICATIO S I FOR ATIO

A Schottky diode in the collector of each NPN transistor of

the NPN input stage allows the LT1637 to operate with

either or both of its inputs above V⁺. At about 0.3V above

V⁺the NPN input transistor is fully saturated and the input

bias current is typically 23µA at room temperature. The

input offset voltage is typically 600µV when operating

aboveV⁺.TheLT1637willoperatewithitsinput44Vabove

V^–regardless of V⁺.

Lower load resistance increases the output crossover

distortion, but has no effect on the input stage transition

distortion. For lowest distortion the LT1637 should be

operated single supply, with the output always sourcing

current and with the input voltage swing between ground

and (V⁺– 0.9V). See the Typical Performance Character-

istics curves.

Gain

The inputs are protected against excursions as much as

22V below V^–by an internal 1.3k resistor in series with

each input and a diode from the input to the negative

supply. There is no output phase reversal for inputs up to

5V below V^–. There are no clamping diodes between the

inputs and the maximum differential input voltage is 44V.

The open-loop gain is less sensitive to load resistance

when the output is sourcing current. This optimizes per-

formance in single supply applications where the load is

returned to ground. The typical performance photo of

Open-Loop Gain for various loads shows the details.

Shutdown

Output

The LT1637 can be shut down two ways: using the

shutdownpinorbringingV⁺towithin0.5VofV^–.WhenV⁺

is brought to within 0.5V of V^–both the supply current and

output leakage current drop to less than 10nA. When the

shutdown pin is brought 1.2V above V^–, the supply

current drops to about 3µA and the output leakage current

islessthan1µA,independentofV⁺.Ineithercasetheinput

bias current is less than 0.1nA (even if the inputs are 44V

above the negative supply).

The shutdown pin can be taken up to 32V above V^–. The

shutdown pin can be driven below V^–, however the pin

currentthroughthesubstratediodeshouldbelimitedwith

an external resistor to less than 10mA.

The output voltage swing of the LT1637 is affected by

input overdrive as shown in the typical performance

curves. When monitoring input voltages within 100mV of

V⁺, gain should be taken to keep the output from clipping.

The output of the LT1637 can be pulled up to 25V beyond

V⁺with less than 1nA of leakage current, provided that V⁺

is less than 0.5V.

The normally reverse biased substrate diode from the

outputtoV^–willcauseunlimitedcurrentstoflowwhenthe

output is forced below V^–. If the current is transient and

limited to 100mA, no damage will occur.

The LT1637 is internally compensated to drive at least

200pF of capacitance under any output loading condi-

tions. A 0.22µF capacitor in series with a 150Ω resistor

between the output and ground will compensate these

amplifiers for larger capacitive loads, up to 4700pF, at all

output currents.

Input Offset Nulling

The input offset voltage can be nulled by placing a 10k

potentiometer between Pins 1 and 8 with its wiper to V^–

(see Figure 1). The null range will be at least ±3mV.

Distortion

There are two main contributors of distortion in op amps:

output crossover distortion as the output transitions from

sourcing to sinking current and distortion caused by

nonlinear common mode rejection. Of course, if the op

amp is operating inverting there is no common mode

induced distortion. When the LT1637 switches between

input stages there is significant nonlinearity in the CMRR.

LT1637

8

1

10k

–

V

1637 F01

Figure 1. Input Offset Nulling

9

LT1637

W

SI PLIFIED SCHE ATIC

+

7

V

Q1

Q13

Q19

Q20

Q25

D1

D2

Q23

R3

R2

6k

1.3k

D3

–IN

+IN

2

3

Q21

Q22

Q24

SHDN

5

Q2

10µA

R4

1.3k

6

OUT

Q9

Q10

Q14 Q15

Q18

R1

1M

Q11

Q12

Q16

Q17

Q26

Q3

Q4

R5

7k

R6

7k

Q6

Q8

D4

D5

Q5

Q7

NULL

1

8

NULL

R7

400Ω

R8

400Ω

–

4

V

1637 SS

U

TYPICAL APPLICATIO S

Optional Output Compensation for

Capacitive Loads Greater Than 200pF

Positive Supply Rail Current Sense

Lamp Outage Detector

+

3V

5V TO 44V

V

1M

200Ω

V

+

IN

LAMP

ON/OFF

100k

5k

LT1637

5V

C

≤ 4700pF

L

–

0.2Ω

+

0.5Ω

OUT

LT1637

Q1

LT1637

2N3904

200Ω

+

0.22µF

150Ω

–

0V TO 4.3V

2k

I

LOAD

OUT = 0V FOR GOOD BULB

3V FOR OPEN BULB

1637 TA02

1637 TA03

V

= (2Ω)(I

)

LOAD

OUT

1637 TA05

Over-The-Top Comparator with Hysteresis

Over-The-Top Current Sense

0.1V TO 44V

1M

R1

200Ω

3V TO 44V

10k

5V

IN1

+

(0V TO 44V)

R

S

+

–

V

0.2Ω

LT1637

1M

OUT

Q1

2N3904

LT1637

–

1M

V

OUT

(0V TO 4.3V)

1M

2N5087

2N5210

I

LOAD

R2

2k

10k

IN2

(0V TO 44V)

V

OUT

LOAD

I

=

LOAD

(R )(R2/R1)

S

1637 TA06

V

CC

100

HYSTERESIS =

1637 TA04

10

LT1637

U

PACKAGE DESCRIPTIO

Dimensions in inches (millimeters) unless otherwise noted.

MS8 Package

8-Lead Plastic MSOP

(LTC DWG # 05-08-1660)

0.118 ± 0.004*

(3.00 ± 0.102)

8

7

6

5

0.040 ± 0.006

(1.02 ± 0.15)

0.034 ± 0.004

(0.86 ± 0.102)

0.007

(0.18)

0° – 6° TYP

0.118 ± 0.004**

(3.00 ± 0.102)

SEATING

PLANE

0.193 ± 0.006

(4.90 ± 0.15)

0.012

(0.30)

REF

0.021 ± 0.006

(0.53 ± 0.015)

0.006 ± 0.004

(0.15 ± 0.102)

0.0256

(0.65)

BSC

MSOP (MS8) 1098

1

2

3

4

* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,

PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE

** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.

INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE

N8 Package

8-Lead PDIP (Narrow 0.300)

(LTC DWG # 05-08-1510)

0.400*

(10.160)

MAX

0.130 ± 0.005

0.300 – 0.325

0.045 – 0.065

(3.302 ± 0.127)

(1.143 – 1.651)

(7.620 – 8.255)

8

1

7

6

5

0.065

(1.651)

TYP

0.255 ± 0.015*

(6.477 ± 0.381)

0.009 – 0.015

(0.229 – 0.381)

0.125

0.020

(0.508)

MIN

(3.175)

MIN

+0.035

–0.015

2

4

3

0.325

0.018 ± 0.003

0.100

(2.54)

BSC

+0.889

8.255

(0.457 ± 0.076)

(

)

N8 1098

–0.381

*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.

MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm)

S8 Package

8-Lead Plastic Small Outline (Narrow 0.150)

(LTC DWG # 05-08-1610)

0.189 – 0.197*

(4.801 – 5.004)

0.010 – 0.020

(0.254 – 0.508)

7

5

8

6

× 45°

0.053 – 0.069

(1.346 – 1.752)

0.004 – 0.010

(0.101 – 0.254)

0.008 – 0.010

(0.203 – 0.254)

0°– 8° TYP

0.150 – 0.157**

(3.810 – 3.988)

0.228 – 0.244

(5.791 – 6.197)

0.016 – 0.050

(0.406 – 1.270)

0.050

(1.270)

BSC

0.014 – 0.019

(0.355 – 0.483)

TYP

*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

1

3

4

2

SO8 1298

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 represen-

tationthattheinterconnectionofitscircuitsasdescribedhereinwillnotinfringeonexistingpatentrights.

11

LT1637

U

TYPICAL APPLICATIO S

Sample-and-Hold

3V

+

V

IN

LT1637

+

–

LT1636

V

OUT

–

150Ω

0.22µF

SHDN

3V

V

1637 TA07

SAMPLE

0V

DROOP (LT1636 BUFFER): 200mV/s

DROOP INTO HIGH IMPEDANCE : LESS THAN 0.625mV/s

MUX Amplifier

MUX Amplifier Waveforms

5V

V

IN1

P-P

+

5kHz AT 4V

LT1637

V

OUT

–

V_OUT

2V/DIV

SHDN

5V

INPUT

–

+

SELECT

LT1637

5V/DIV

V

IN2

10kHz AT 2V

P–P

0.2ms/DIV

1637 TA08

SHDN

INPUT SELECT

1kHz AT 5V

P–P

1637 TA09

74HC04

RELATED PARTS

PART NUMBER

DESCRIPTION

COMMENTS

Input/Output Common Mode Includes Ground, 70µV V

and 2.5µV/°C Drift (Max), 200kHz GBW, 0.07V/µs Slew Rate

LT1078/LT1079

LT2078/LT2079

Dual/Quad 55µA Max, Single Supply, Precision Op Amps

Dual/Quad 17µA Max, Single Supply, Precison Op Amps

Dual/Quad Precision, Rail-to-Rail Input and Output Op Amps

OS(MAX)

LT1178/LT1179

LT2178/LT2179

Input/Output Common Mode Includes Ground, 70µV V

OS(MAX)

and 4µV/°C Drift (Max), 85kHz GBW, 0.04V/µs Slew Rate

LT1366/LT1367

LT1490/LT1491

475µV V , 500V/mV A , 400kHz GBW

OS(MAX)

VOL(MIN)

Dual/Quad Over-The-Top Micropower, Rail-to-Rail Input and

Output Op Amps

Single Supply Input Range: –0.4V to 44V, Micropower 50µA

per Amplifier, Rail-to-Rail Input and Output, 200kHz GBW

LT1636

Single Over-The-Top Micropower Rail-to-Rail Input and Output

Op Amp

55µA Supply Current, V

Extends 44V above V ,

CM EE

Independent of V ; MSOP Package, Shutdown Function

CC

LT1638/LT1639

LT1782

Dual/Quad 1.2MHz Over-The-Top Micropower, Rail-to-Rail

Input and Output Op Amps

0.4V/µs Slew Rate, 230µA Supply Current per Amplifier

Micropower, Over-The-Top, SOT-23, Rail-to-Rail

Input and Output Op Amp

SOT-23, 800µV V , I =55µA (Max),

OS(MAX) S

Gain-Bandwidth = 200kHz, Shutdown Pin

LT1783

1.2MHz, Over-The-Top, Micropower, Rail-to-Rail

Input and Output Op Amp

SOT-23, 800µV V , I =300µA (Max),

Gain-Bandwidth = 1.2MHz, Shutdown Pin

OS(MAX)

S

1637f LT/TP 0100 4K • PRINTED IN USA

12 ^{LinearTechnology Corporation}

1630 McCarthy Blvd., Milpitas, CA 95035-7417

●

(408)432-1900 FAX:(408)434-0507 www.linear-tech.com

LINEAR TECHNOLOGY CORPORATION 1999


型号：	LT1637
厂家：	Linear
描述：	1.1MHz, 0.4V/us Over-The-Top Micropower, Rail-To-Rail Input and Output Op Amp 为1.1MHz ， 0.4V / us的过顶的微功耗，轨至轨输入和输出运算放大器运算放大器
文件：	总12页 (文件大小：258K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

LT1637 [Linear]

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