Agilent Technologies L4400 - Manual (Page 236)

224 L4400 User’s Guide
9 L4451A 4-Channel Isolated D/A Converter with Waveform Memory
L4451A 4-Channel Isolated D/A Converter with Waveform Memory
The L4451A 4- Ch Isolated D/A module (DAC module) has four
independent, isolated DAC channels that output DC voltage up to

16V or
DC current up to

20 mA. Since the DACs are electrically isolated, you
can stack or combine multiple DACs to have up to

64 V on a module.
You can control each channel manually, or use the onboard memory to
store multiple sequenced points.
Level Output Mode
The module can generate voltages between - 16 V DC and +16 V DC at
500

V resolution on any channel. Each channel configured for voltage
output has hardware remote- sensing capability to ensure that an
accurate voltage is present at the load. With the remote sensing feature,
the DAC channel outputs an additional voltage to compensate for the
voltage drop in the test leads. Thus, using the sense connections, the
load voltage equals the programmed voltage as long as the resistance in
each sense lead is less than 2.5
 and the maximum voltage drop in the
output leads is 0.5 volts.
To ensure that an accurate voltage is present at the loads, it is
recommended that you use remote-sensing. However, if
remote-sensing is not used, do not connect loads or cables to the
remote-sensing terminals (H Sense and L Sense).
When using the remote- sensing feature, connect sense wires from the
load to the High Sense and Low Sense terminals for the desired
channels.
Each channel can also generate current between - 20 mA and +20 mA at

630 nA resolution. When outputting current the High Sense and Low
Sense terminals
are not used and are opened. For protection, each
channel incorporates a fuse that will open at greater than 20 mA. If an
overload condition exists, the fuse will open, but no error or SRQ will be
generated. To reset the fuse, remove the overload condition and wait a
few minutes for the fuse to cool.
Waveform (Trace) Mode
Using the internal waveform point storage, you can output provided sine,
square, or ramp and triangle wave shapes, or define your own wave
shape with up to 512,000 points. The module can output points with a
settling time of 40

s and a 200 kHz point- to- point update rate.
N O T E