Series Operation; Parallel Operation; Output Ripple & Noise - TDK-Lambda SWS-L Series Manual

SWS
600L, 1000L
(a)
2.2KΩ
150Ω
12V
typ
Example V1:5V R1:620Ω)
(b)
2.2KΩ
150Ω
12V
typ
(c)
2.2KΩ
150Ω
12V
typ
Fig.2.3 Examples of connecting remote ON/OFF circuit
Output Ripple & Noise
The standard specifi cation for maximum ripple value is mea-
sured by measurement circuit as below. When load lines are
longer, ripple becomes larger. In this case, electrolytic capaci-
tor, fi lm capacitor, etc. might be necessary to use across the
load terminal. The output ripple cannot be measured accurately
if the probe ground lead of oscilloscope is too long.
150mm
+
Power
47µ
Supply
0.1µ
-
・All specifications are subject to change without notice.
AUX
CNT1
V1
CNT2
R1
SW
TOG
G2
AUX
CNT1
CNT2
TOG
SW
G2
AUX
CNT1
CNT2
SW
TOG
G2
Load
Coaxial Cable
Oscilloscope
1.5m
20MHz

Series Operation

For series operation, both method (A) and (B) are possible.
There might be a step in the output rise waveform during series
operation.
Method (A)
Power Supply
+S
+Vm
-Vm
-S
+S
+Vm
-Vm
-S
Method (B)
Power Supply
+S
+Vm
-Vm
-S
+S
+Vm
-Vm
-S

Parallel Operation

Current balancing function is provided. Both operations mode
(A) and (B) are possible.
(A) To Increase the Output Current
Correct PC to PC terminal and COM to COM terminal, the current
balancing function activates and output current of each power
supply is equivalently supplied to load. Wires to PC terminals,
COM terminals shall be as short as possible and same length
and twisted.
(1) Adjust the output voltage of each power supply to be same
value within 1% or 100mV whichever is smaller.
(2) Use same length and type of wires for all load lines.
(3) Please make sure that the sum of output current values
does not exceed a value obtained from the right side of fol-
lowing equation.
Maximum of total output current in parallel operation
Rated current per unit × Number of units × 0.9
(4) Parallel operation is possible up to 5 units.
(B) To Use as a Backup Power Supply
(1) Adjust the output voltage (Vo) of each power supply to be
same value within 1% or 100mV whichever is smaller.
(2) Set power supply output voltage higher to compensate the
forward voltage drop of diode.
(3) Use within the specifi cations for output voltage and output
current.
(4) When one of power supplies fails, the remaining non-failure
power supplies continue to maintain the output. If one of
the power supplies stop operating, the output voltage may
Load
Load
Load
≤
13