PQ60120QZB33 Datasheet, PDF (12/13 Pages) SynQor Worldwide Headquarters – Protection from permanent damage and hazardous conditions

Applications Section
Technical
Specification
PQ60120QZB33
140
120
100
80
60
40
20
0
35
40
45
50
55
60
65
Vin (V)
Figure E: Output Voltage Resolution example for 12Vout units.
= 12.0 Vout
= 10.0 Vout
≤ 8.75 Vout
70
75
Figure F: Smallest Possible Vout Step example for 12Vout unit at 48Vin..
Limited Output Voltage Resolution: The internal voltage
control feedback loop has limited resolution. Therefore, the
output voltage will exhibit discrete steps as the loop responds to
changes in line, load, trim, or remote sense. For instance, on close
examination, the startup ramp has a “stair-step” shape. Likewise, a
load transient response will be composed of multiple discrete steps.
The size of each step is well determined, and is shown in Figure E.
A close-up picture of a single step is shown in Figure F. Stepping
will not occur under steady state conditions.
Active Trim Not Recommended: It is important to note that
external feedback control using the sense or trim pins will cause
sustained stepping. External current share or active trim circuits
contain a separate reference voltage. After this external feedback
has taken control, the actual output voltage can still differ from
the external reference voltage by as much as the step size. If the
external feedback loop integrates this error volt-age, it will cause a
limit cycle oscillation. For this reason, external feedback using the
sense and trim pins is not recommended.
Product # PQ60120QZB33
Phone [phone]
www.synqor.com
Doc.# 005-0005586 Rev. G
02/04/15
Page 12