1

LT1638/LT1639

1.2MHz, 0.4V/

µs

Over-The-Top

Rail-to-Rail Input and Output

Op Amps

FEATURES

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Rail-to-Rail Input and Output

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Low Power: 230

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Gain Bandwidth Product: 1.2MHz

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Slew Rate: 0.4V/

µs

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High Output Current: 25mA Min

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Specified on 3V, 5V and

±15V Supplies

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Reverse Battery Protection to 18V

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No Supply Sequencing Problems

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High Voltage Gain: 1500V/mV

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Single Supply Input Range: – 0.4V to 44V

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High CMRR: 98dB

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No Phase Reversal

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Battery- or Solar-Powered Systems

Portable Instrumentation

Sensor Conditioning

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Supply Current Sensing

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Battery Monitoring

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Micropower Active Filters

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4mA to 20mA Transmitters

V1

V2

V0

–

+

A

1/2 LT1638

–

+

B

1/2 LT1638

1M

1M

1M

10k

10k

1638/39 TA01

1M

Over-The-Top Comparator with 100mV Hysteresis Centered at 0mV

Output Voltage vs Input Voltage

5V

0V

The LT

operational amplifier available in the standard 8-pin PDIP and

SO packages as well as the 8-lead MSOP package. The

LT1639 is a low power quad rail-to-rail input and output

operational amplifier offered on the standard 14-pin PDIP

and surface mount packages.

The LT1638/LT1639 op amps operate on all single and

split supplies with a total voltage of 2.5V to 44V drawing

only 170

µA of quiescent current per amplifier. These

amplifiers are reverse battery protected and draw no

current for reverse supply up to 18V.

The input range of the LT1638/LT1639 includes both

supplies, and a unique feature of this device is its capability

to operate over the top with either or both of its inputs

common mode, independent of supply voltage. The input

stage incorporates phase reversal protection to prevent

false outputs from occurring even when the inputs are 22V

below the negative supply. Protective resistors are

included in the input leads so that current does not

become excessive when the inputs are forced below the

negative supply. The LT1638/LT1639 can drive loads up to

25mA and still maintain rail-to-rail capability. The op amps

are unity-gain stable and drive all capacitive loads up to

1000pF when optional output compensation is used.

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

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

1638/39 TA02