Linear Technology LT1221MJ8, LT1221CS8, LT1221CN8 Datasheet

FEATURES

■

Gain-Bandwidth: 150MHz

■

Gain of 4 Stable

■

Slew Rate: 250V/µs

■

Input Noise Voltage: 6nV/√Hz

■

C-LoadTM Op Amp Drives Capacitive Loads

■

Maximum Input Offset Voltage: 600µV

■

Maximum Input Bias Current: 300nA

■

Maximum Input Offset Current: 300nA

■

Minimum Output Swing Into 500Ω: ±12V

■

Minimum DC Gain: 50V/mV, RL = 500Ω

■

Settling Time to 0.1%: 65ns, 10V Step

■

Settling Time to 0.01%: 85ns, 10V Step

■

Differential Gain: 0.08%, AV = 4, RL = 150Ω

■

Differential Phase: 0.2°, AV = 4, RL = 150Ω

U

APPLICATIO S

■

Wideband Amplifiers

■

Buffers

■

Active Filters

■

Video and RF Amplification

■

Cable Drivers

■

8-, 10-, 12-Bit Data Acquisition Systems

LT1221

150MHz, 250V/µs, AV ≥ 4

Operational Amplifier

U

DESCRIPTIO

The LT®1221 is a very high speed operational amplifier
with superior DC performance. The LT1221 is stable in a
noise gain of 4 or greater. It features reduced input offset
voltage, lower input bias currents and higher DC gain than
devices with comparable bandwidth and slew rate. The
circuit is a single gain stage that includes proprietary DC
gain enhancement circuitry to obtain precision with high
speed. The high gain and fast settling time make the circuit
an ideal choice for data acquisition systems. The circuit is
also capable of driving capacitive loads which makes it
useful in buffer or cable driver applications.

The LT1221 is a member of a family of fast, high perfor­mance amplifiers that employ Linear Technology
Corporation’s advanced complementary bipolar process­ing. For unity-gain stable applications the LT1220 can be
used, and for gains of 10 or greater the LT1222 can be used.

, LTC and LT are registered trademarks of Linear Technology Corporation

C-Load is a trademark of Linear Technology Corporation

TYPICAL APPLICATIO

Summing Amplifier

1k

V

A

1k

V

B

1k

V

C

1k

–

LT1221

+

U

V

OUT

LT1221 • TA01

Summing Amplifier Large-Signal Response

VS = ±15V

= 10V

V

IN

f = 2MHz

P-P

LT1221 • TA02

1

LT1221

A

W

O

LUTEXI TIS

S

A

WUW

U

(Note 1)

ARB

G

Total Supply Voltage (V+ to V–) ............................. 36V

Differential Input Voltage ........................................ ±6V

Input Voltage .......................................................... ±V

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

Specified Temperature Range

LT1221C (Note 3)................................... 0°C to 70°C

LT1221M (OBSOLETE) ............... –55°C to 125°C

WU

/

+IN

1

2

3

H PACKAGE

= 175°C, θ

O

RDER I FOR ATIO

TOP VIEW

NULL

8

4

–

V

JA

+

V

7

6

5

NC

= 150°C/W

V

OUT

ORDER PART

NUMBER

SPECIAL

ORDER

CONSULT

FACTORY

PACKAGE

NULL

–IN

8-LEAD TO-5 METAL CAN

T

JMAX

Operating Temperature Range

LT1221C........................................... –40°C TO 85°C

S

LT1221M (OBSOLETE) ............... –55°C to 125°C

Maximum Junction Temperature (See Below)

Plastic Package ............................................... 150°C

Ceramic Package (OBSOLETE) .................. 175°C

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

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

U

NULL

1

–IN

2

+IN

3

–

V

4

N8 PACKAGE

8-LEAD PLASTIC DIP

T

= 150°C, θ

JMAX

T

= 150°C, θ

JMAX

J8 PACKAGE

8-LEAD CERAMIC DIP

T

= 175°C, θ

JMAX

TOP VIEW

8
7
6
5

S8 PACKAGE

8-LEAD PLASTIC SOIC

= 130°C/W (N)

JA

= 190°C/W (S)

JA

= 100°C/W (J)

JA

NULL

+

V
V

OUT

NC

ORDER PART

NUMBER

LT1221CN8
LT1221CS8

S8 PART MARKING

1221

ORDER PART

NUMBER

OBSOLETE PACKAGE

Consider the N8 or S8 Package for Alternate Source

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

ELECTRICAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OS

I

OS

I

B

e

n

i

n

R

IN

C

IN

CMRR Common Mode Rejection Ratio VCM = ±12V 92 114 dB
PSRR Power Supply Rejection Ratio VS = ±5V to ±15V 90 110 dB
A

VOL

V

OUT

I

OUT

SR Slew Rate (Note 5) 200 250 V/µs

GBW Gain-Bandwidth f = 1MHz 150 MHz

Input Offset Voltage (Note 4) 200 600 µV
Input Offset Current 100 300 nA
Input Bias Current 100 300 nA
Input Noise Voltage f = 10kHz 6 nV/√Hz
Input Noise Current f = 10kHz 2 pA/√Hz
Input Resistance VCM = ±12V 20 45 MΩ

Differential 80 kΩ

Input Capacitance 2pF
Input Voltage Range (Positive) 12 14 V

Input Voltage Range (Negative) –13 – 12 V

Large-Signal Voltage Gain V
Output Swing RL = 500Ω 12 13 ±V
Output Current V

Full Power Bandwidth 10V Peak (Note 6) 4 MHz

TA = 25°C, VS = ±15V, TA = 25°C, VCM = 0V, unless otherwise specified.

= ±10V, RL = 500Ω 50 100 V/mV

OUT

= ±12V 24 26 mA

OUT

OBSOLETE PACKAGE

Consider the N8 Package for Alternate Source

LT1221MJ8

2

LT1221

ELECTRICAL CHARACTERISTICS

VS = ±15V, TA = 25°C, VCM = 0V, unless otherwise specified.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

tr, t

f

Rise Time, Fall Time AV = 4, 10% to 90%, 0.1V 3.2 ns
Overshoot AV = 4, 0.1V 10 %
Propagation Delay AV = 4, 50% VIN to 50% V

t

s

Settling Time 10V Step, 0.1% 65 ns

, 0.1V 5.4 ns

OUT

10V Step, 0.01% 85 ns

Differential Gain f = 3.58MHz, RL = 150Ω (Note 7) 0.08 %

f = 3.58MHz, R

= 1k (Note 7) 0.02 %

L

Differential Phase f = 3.58MHz, RL = 150Ω (Note 7) 0.20 DEG

f = 3.58MHz, RL = 1k (Note 7) 0.05 DEG

R

O

I

S

Output Resistance AV = 4, f = 1MHz 0.3 Ω
Supply Current 8 10.5 mA

The ● denotes the specifications which apply over the temperature range 0°C ≤ TA ≤ 70°C, otherwise specifications are at TA = 25°C.
VS = ±15V, VCM = 0V, unless otherwise specified.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OS

Input Offset Voltage (Note 4) ● 0.2 1.5 mV
Input VOS Drift ● 15 µV/°C

I

OS

I

B

Input Offset Current ● 100 400 nA
Input Bias Current ● 100 400 nA

CMRR Common Mode Rejection Ratio VCM = ±12V ● 92 114 dB
PSRR Power Supply Rejection Ratio VS = ±5V to ±15V ● 90 110 dB
A
V
I

VOL
OUT

OUT

Large-Signal Voltage Gain V

= ±10V, RL = 500Ω ● 40 100 V/mV

OUT

Output Swing RL = 500Ω ● 12 13 ±V
Output Current V

= ±12V ● 24 26 mA

OUT

SR Slew Rate (Note 5) ● 180 250 V/µs
I

S

Supply Current ● 811 mA

The ● denotes the specifications which apply over the temperature range –55°C ≤ TA ≤ 125°C, otherwise specifications are at
TA = 25°C. VS = ±15V, VCM = 0V, unless otherwise specified.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OS

I

OS

I

B

CMRR Common Mode Rejection Ratio VCM = ±12V ● 92 114 dB
PSRR Power Supply Rejection Ratio VS = ±5V to ±15V ● 90 110 dB
A

VOL

V

OUT

I

OUT

SR Slew Rate (Note 5) ● 130 250 V/µs
I

S

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

Note 2: A heat sink may be required when the output is shorted indefinitely.
Note 3: Commercial parts are designed to operate over –40°C to 85°C, but

are not tested nor guaranteed beyond 0°C to 70°C. Industrial grade parts
specified and tested over –40°C to 85°C are available on special request.
Consult factory.

Input Offset Voltage (Note 4) ● 0.2 2 mV
Input VOS Drift ● 15 µV/°C
Input Offset Current ● 100 800 nA
Input Bias Current ● 100 1000 nA

Large-Signal Voltage Gain V

= ±10V, RL = 500Ω ● 12.5 100 V/mV

OUT

Output Swing RL = 500Ω ● 10 13 ±V

RL = 1k ● 12 13 ±V

Output Current V

= ±10V ● 20 26 mA

OUT

= ±12V ● 12 13 mA

V

OUT

Supply Current ● 811 mA

Note 4: Input offset voltage is pulse tested and is exclusive of warm-up drift.
Note 5: Slew rate is measured between ±10V on an output swing of ±12V.
Note 6: FPBW = SR/2πV

.

P

Note 7: Differential Gain and Phase are tested in AV = 4 with five amps in
series. Attenuators of 1/4 are used as loads (36.5Ω, 110Ω and
249Ω, 750Ω).

3

LT1221

FREQUENCY (Hz)

100

0

POWER SUPPLY REJECTION RATIO (dB)

10

20

40

60

80

100

1k 100k 10M 100M

LT1221 • TPC09

10k 1M

VS = ±15V

T

A

= 25°C

–PSRR

+PSRR

W

U

TYPICAL PERFORMANCE CHARACTERISTICS

Input Common Mode Range
vs Supply Voltage

20

TA = 25°C

= 0.5mV

∆V

OS

15

10

5

MAGNITUDE OF INPUT VOLTAGE (V)

0

0

5101520

SUPPLY VOLTAGE (±V)

+V

–V

Output Voltage Swing
vs Resistive Load

30

TA = 25°C

= 30mV

∆V

P-P

OS

25

20

±15V SUPPLIES

15

10

5

0

10

LOAD RESISTANCE (Ω)

±5V SUPPLIES

100 1k 10k

)

OUTPUT VOLTAGE SWING (V

CM

CM

LT1221 • TPC01

LT1221 • TPC04

Supply Current vs Supply Voltage
and Temperature

11

10

T = 125°C

9

8

7

SUPPLY CURRENT (mA)

6

5

0

5101520

SUPPLY VOLTAGE (±V)

T = 25°C

T = –55°C

Input Bias Current
vs Input Common Mode Voltage

500

TA = 25°C

400

= ±15V

V

S

300
200
100

0
–100
–200

INPUT BIAS CURRENT (nA)

–300

–400
–500

–10 –5 10

–15

INPUT COMMON MODE VOLTAGE (V)

+

I

B

–

I

B

05 15

LT1221 • TPC02

LT1221 • TPC05

Output Voltage Swing
vs Supply Voltage

20

TA = 25°C

= 500Ω

R

L

= 30mV

∆V

OS

15

+V

10

–V

SW

5

MAGNITUDE OF OUTPUT VOLATGE (V)

0

0

5101520

SUPPLY VOLTAGE (±V)

Open-Loop Gain
vs Resistive Load

110

TA = 25°C

100

VS = ±15V

90

80

OPEN-LOOP GAIN (dB)

70

60

10

100 1k 10k

LOAD RESISTANCE (Ω)

SW

LT1221 • TPC03

VS = ±5V

LT1221 • TPC06

Output Short-Circuit Current
vs Temperature

50

VS = ±5V

45

40

35

30

25

OUTPUT SHORT-CIRCUIT CURRENT (mA)

20

4

–50

025 75

–25 50 100 125

TEMPERATURE (°C)

LT1221 • TPC07

Input Noise Spectral Density

1000

100

10

INPUT NOISE VOLTAGE (nV/√Hz)

1

10 1k 10k 100k

100

i

n

e

n

FREQUENCY (Hz)

VS = ±15V
T
A
R

= 25°C

A

= 101

V

= 100k

S

LT1221 • TPC08

Power Supply Rejection Ratio
vs Frequency

100

INPUT NOISE CURRENT (pA/√Hz)

10

1

0.1