Instructions

AP033 Active Differential Probe
16
To invoke AutoZero, either:
• Touch AutoZero on the AP033 dialog.
• In Manual mode, or if the probe is being used with the ADPPS power supply,
push and hold the
↑
and
↓
OFFSET buttons at the same time for two seconds.
(This action is labeled AUTO BAL on the probe body).
The AP033 output must be terminated into 50Ω for successful AutoZero.
Upon successful completion of the AutoZero cycle, all four of the EFFECTIVE GAIN
indicators will be briefly illuminated. If an input signal is present and the routine fails, the
EFFECTIVE GAIN indicators will not illuminate. The probe will then revert to the offset
values that resulted from the last successful completion of the AutoZero cycle. In many
situations, this will be adequate to make routine measurements.
Designing Test Fixtures for the AP033 Probe
Often it is desirable to connect the probe directly to user fabricated test fixtures, such as
those used for semiconductor characterization. To facilitate use with custom test fixtures,
the input receptacles of the AP033 probe are compatible with commercially available
0.025 in. (0.635 mm) square pins. The receptacles do not require a specific rotational
alignment for the square pin. The dimensions listed below can be used as a layout guide
for a test fixture circuit board. The recommended insertion depth of the pins is 0.100 in.
(2.5 mm) to 0.200 in. (5.0 mm).
Figure 7, Layout dimensions for test fixtures