1 Features
1• (Maximum Limit, 25°C Unless Otherwise Noted)
• Input Current (100% Tested): 25 fA
• Input Current Over Temperature: 2 pA
• Low Power: 750 μA
• Low VOS: 350 μV
• Low Noise: 22 nV/√Hz at 1 kHz Typical

2 Applications
• Electrometer Amplifiers
• Photodiode Preamplifiers
• Ion Detectors
• A.T.E. Leakage Testing

3 Description
Featuring 100% tested input currents of 25 fA
maximum, low operating power, and ESD protection
of 2000 V, the LMC6001 device achieves a new
industry benchmark for low input current operational
amplifiers. By tightly controlling the molding
compound, Texas Instruments is able to offer this
ultra-low input current in a lower cost molded
package.
To avoid long turnon settling times common in other
low input current op amps, the LMC6001A is tested
three times in the first minute of operation. Even units
that meet the 25-fA limit are rejected if they drift.
Because of the ultra-low input current noise of 0.13
fA/√Hz, the LMC6001 can provide almost noiseless
amplification of high resistance signal sources.
Adding only 1 dB at 100 kΩ, 0.1 dB at 1 MΩ and 0.01 dB or less from 10 MΩ to 2,000 MΩ, the LMC6001 is
an almost noiseless amplifier.
The LMC6001 is ideally suited for electrometer applications requiring ultra-low input leakage such as
sensitive photodetection transimpedance amplifiers
and sensor amplifiers. Because input referred noise is
only 22 nV/√Hz, the LMC6001 can achieve higher signal to noise ratio than JFET input type
electrometer amplifiers. Other applications of the LMC6001 include long interval integrators, ultra-high
input impedance instrumentation amplifiers, and
sensitive electrical-field measurement circuits.