Fig 1-11 Rise Time Transition Limitation - Prodigit 3110 Series Operation Manual

6 PRODIGIT
In cases where the transition from one setting to another is small, the small signal
bandwidth (of the load) limits the minimum transition time for all programmable slew rates.
Because of this limitation, the actual transition time is longer than the expected time based
on the slew rate, as shown in Figure 1-11
Therefore, both minimum transition time and slew rate must be considered when
determining the actual transition time.
Following detail description is exclude in operation manual.
The minimum transition time for a given slew rate as about a 30% or greater load change,
The slew rate increases from the minimum transition time to the Maximum transition time at
a 100% load change. The actual transition time will be either the minimum transition time,
Or the total slew time (transition divided by slew rate), whichever is longer.
EX: 3110 80V/50A/250W (CCH - CCL >50.4Ax 30%)
Use the following formula to calculate the minimum transition time for a given slew rate
Min transition time=18A/slew rate (in amps/second).
7.56uS (15.12A/2) x 0.8(10%~90%) =6.048uS
Use the following formula to calculate the maximum transition time for a given slew rate
Max transition time=60/slew rate (in amps/second).
25.2uS (50.4A/2) x 0.8(10~90%) = 20.16uS
EX. CCH=10.08A, CCL=0A Slew Rate =2A/uS, the expected time is 128uS but the actual
Transition Time will be limited to 144uS
5.04uS (10.08A/2) x 0.8(10%~90%) = 4.032uS
Slew Rate
Slew Rate
100 %
90 %
Expected time
Actual Time

Fig 1-11 Rise Time Transition Limitation

10 %
0 %
Time
mS