AMETEK HPD Series GPIB-Multichannel User Manual
Page 71
Operation
Auto Sequencing
67
Slew Rate
The slew rate is calculated as a function of change in the output voltage and a given
time interval. The maximum slew rate is 1% rated voltage/150us. The slew rate is
saved upon power off and restored at power on. Output ON/OFF and shutdown are
not affected by the programmable slew rate. These functions have a slew rate of
1%/20ms.
The range of output voltage is 5% - 0.1% of rated voltage.
The range of time interval is 1.5 s - 150 us.
The negative slew rate is limited by the discharge rate of the output capacitors.
During current share, slaves operate with their default slew rate. The master operates
at its programmed slew rate. Hence a programmable slew rate for the system is
achieved. However, this slew rate is limited by the speed of the control loop. The
slaves will return to their programmed slew rate when they exit current share slave
operation.
The slew rate error increases as the slew rate increases.
The SCPI commands for changing the voltage slew rate are:
:VOLT:SLEW:STEP {
where voltage-step has the units V, mV, etc.
and the range is 0.1% to 5% of rated voltage for the power supply.
default step is 0.1% of rated output voltage.
query returns value in volts.
:VOLT:SLEW:INTerval {
where time interval has the units s, ms, or us
and the range is 150 us to 1.5s
default interval is 150us.
query returns value in volts.
Selecting DEFAULT for both settings will return the slew rate to the default value
of 1% rated voltage per 150us.
The combination must not exceed 1%/150us. Though the software will attempt to
achieve higher slew rates, it is limited to this value by hardware constraints.
Manufacturer's recommendation is to keep the slew rate at or below the default
value.
!
CAUTION
Check both the voltage step and the interval to ensure you get the required slew rate.