General Test & Measuring Instruments

Digital Nano Ammeter, Model: DNM -121


  • Measures current down to 100pA
  • All solid state and IC design
  • Accepts either polarity of input current

Digital Nanoammeter, DNM-121, a rugged and low cost instrument, is a product of extensive R&D using high input impedance integrated circuits. It has 4 decade ranges with 100% overranging. The unit is suitable for current measurement in the range of 100pA to 200μA. For the ease, readings are directly obtained on a 3½ digit DPM. The instrument is capable of accepting either polarity of the input current. The very low leakage current of the input stage combined with the high linearity fast response due to high negative feedback enables accurate and easily reproducible measurements. The instrument uses a FET input operational amplifier that offers the very low input bias current, low offset voltage, low drift and noise. These characteristics have been fully utilized in the present Nanoammeter. This operational amplifier is used in low level current to voltage configuration.


  • To measure current from photomultiplier tubes, photometer etc.
  • Leakage currents in solid state devices. FET gate and tube grid voltages without loading errors.
  • Current through very high resistance in conjunction with a power supply.
  • Potentials across semiconductors, piezoelectric systems & pH electrodes.


  •  Range : 100nA, 1μA, 10μA, 100μA with 100% over-ranging
  • Accuracy : 0.2% for all ranges
  • Resolution : 0.1nA
  • Input Resistance : 25W, 2.5W, 0.25W, 0.025W
  • Display : 3½ digit 7 segment LED (12.5mm height) with auto polarity and decimal indication
  • Input : Through amphenol connector
  • Power Supply : 220V ±10%, 50Hz
  • Weight : 2.5Kg
  • Dimensions : 240mm X 275mm X 120mm 

Note: There may be any change in specification due to continuous R & D without notice.