Agilent Technologies 6681A Constant Current CC Tests, Current Programming and Readback Accuracy

Constant Current (CC) Tests

Test Setup

Connect the appropriate current monitoring resistor (see Table 2-l) as shown in Fig. 2-3. The accuracy of the resistor must be as specified in the table.

Test Procedures

The test procedures are given in Table 2-5. The tests are independent and may be performed in any order. The CC tests are:

•Current Programming and Readback Accuracy.

•CC Load Effect.

•CC Source Effect.

•CC Noise (PARD).

Table 2-5. Constant Current (CC) Tests

Action Normal Result

Current Programming and Readback Accuracy

This test verifies that the current programming and readback are within specification.

1

2

3

4

5

6

7

Turn off the power supply and connect the current monitoring resistor as shown in Fig. 2-3. Connect a DVM across the resistor .

Turn on the power supply and program the output for 5 volts and 0 amperes.

Short the load.

Observe the DVM voltage reading. Divide this by the resistance of the current monitor resistor. Record the result as the Low Current value.

Record the front panel display readback.

Program output current to full scale (see Table 2-2).

Repeat Steps 4 and 5.

Value within specified Low Current limits.

Value within specified readback limits.

Both current readings within specified High Current and readback limits.

CC Noise (PARD)

Periodic and random deviations (PARD) in the output (ripple and noise) combine to produce a residual ac current superimposed on the dc output current. This test measures CC PARD, specified as the rms output current over the frequency range of 20 Hz to 20 MHz.

1

Turn off the power supply and connect the current transformer, resistor, capacitor and rms voltmeter (see Fig. 2-4).

Verification 19