Advantest R8340 高阻表的产品介绍：

The R8340A digital ultra-high resistance/micro current meters
use an input amplifier gain switching type I-V converter, highspeed
sampling A/D converter and low-noise high-response
voltage generator. They are fast and precise, with a range from
10 fA to 19.999 mA for current measurement and 10 Ħ to 3 ?~ 1016
Ħ for resistance measurement.

Key Features

- Measurement of Micro Current from 10 fA to 19.999 mA
- Measurement of High Resistance from 10 Ħ to 3 ?~ 1016 Ħ
- High-Speed Charge/Discharge
- High-Speed Measurement with 100 Samples/Second
- Floating Measurement of 1100 VDC
- Standard GPIB Interface 

See Spec Sheet for Addional Information