ORTEC Logo

Home | Applications | Contact Us
Products | Service | Training
Download PDF

   Order Online

439-fp.jpg (27526 bytes)

439-rp.jpg (9515 bytes)

 439 Digital Current Integrator

PERFORMANCE

LEAKAGE IMPEDANCE FROM INPUT TO GROUND >1 X 1010 Ω.

INPUT LEAKAGE CURRENT <1 X 10–12 A.

TEMPERATURE INSTABILITY ≤±0.05%/°C, 0 to 50°C.

DIGITIZED OUTPUT INACCURACY Readings from 100 nA to 10 mA dc, ≤±0.2%; for 50 nA, typically ±0.3% (count rate on 10–10 coulomb/pulse range limited to 1 kHz).

DIGITIZED REPRODUCIBILITY 0.01%.

ANALOG ACCURACY Front-panel meter 2%; rear-panel binding posts 1.5%.

CONTROLS AND INDICATOR

MULTIPLIER Front-panel switch determines the multiplier to be applied to the Current F.S. reading to produce a full-scale deflection on the Ampere Meter.

CURRENT F.S. AND COUL/PULSE Front-panel switch, controls amount of charge that must be injected at the input to obtain a digital output pulse (low, medium, and high selection for each).

TEST-OPERATE Front-panel 3-position switch controls the function of the Model 439:
Test Internal test current is provided to produce an output of ~1000 Hz on all coulomb/pulse ranges.
Standby Grounds the input of the Model 439 preventing application of transients to the input amplifier.
Operate Position in which the Model 439 will normally be used; connects the input amplifier to the front- and rear-panel SHV input connectors.

POLARITY Front-panel switch selects the polarity, Pos or Neg, of the input current to be measured.

BAL/TRIG Front-panel switch used in conjunction with Bal/Trig Meter and Test-Operate switch balances and adjusts the Model 439 input amplifier.

OFFSET/CURRENT Rear-panel potentiometer adjusts the input offset current over a range of ~±10 pA.

INPUTS

SIGNAL INPUT Through front- and rear-panel SHV connectors.
Impedance Virtually ground with maximum excursion of <±5 mV.
Current Polarity Positive or negative.
Current Range 1 X 10–9 to 1 X 10–2 A.

GATE Signal normally enabled in absence of an input or when the dc value is nominally +6 V; front- and rear-panel BNC connectors.
To Enable Output +3 V or greater.
To Inhibit Output +1.5 V or less (e.g., can be shorted to ground by a relay).
Maximum Input +25 V, –10 V.
Duty Cycle Limitation None, dc-coupled.
Input Impedance >1000 W; driving source must be capable of sinking 1 mA of current from a positive source.

OUTPUTS

DIGITIZED Signal +5 V, 500 ns wide; 0 to 10 kHz; front- and rear-panel BNC connectors.

ANALOG
Front-Panel Meter 0–1 and 0–3 scales serving all multiplier ranges. There are 15 full-scale ranges.
Rear-Panel Binding Posts 0 to 1 mA full scale; 0 to 100 mV full scale; 0 to 10 mV full scale. There are 15 full-scale ranges.

ELECTRICAL AND MECHANICAL

POWER REQUIRED The Model 439 derives its power from a standard NIM bin/power supply, such as the ORTEC Model 4001A/4002A. Required power is +24V, 45 mA; –24 V, 45 mA; +12 V, 95 mA; –12 V, 110 mA.

WEIGHT
Net 1.7 kg (3.75 lb).
Shipping 3.06 kg (6.75 lb).

DIMENSIONS NIM-standard triple-width module 10.28 X 22.13 cm (4.05 X 8.714 in.) front panel per DOE/ER-0457T.

RELATED EQUIPMENT

The Model 439 may be combined with an ORTEC preset counter to form a digital charge integrator or with a counter and timer to form a digital electrometer.

ORDERING INFORMATION
 

Model   Description
439   Digital Current Integrator