®
IMX35 Series Data Sheet
35 Watt Quad-Output DC-DC Converters
Functional Description
The IMX35 converters are comprised of 2 feedback-controlled
interleaved-switching flyback power trains using current mode
PWM (pulse width modulation).
Each converter consists of 4 electrically isolated outputs
deriving from 2 power trains. Vo1, Vo4 derive from the first
power train and Vo2, Vo3 from the second one. Thus each pair
of outputs is independent from the other one.
Voltage regulation for each pair of outputs is achieved with
passive transformer feedback from the main transformer of the
power train. Each pair of outputs has the same output voltage
(i.e. D05, D12, etc.). If both power trains have the same output
voltage (e.g. D12D12), all outputs may be simultaneously
adjusted by the Trim input (pin 5). In case of different output
voltages (e.g. D05D15), the Trim1 input influences only Vo1
and Vo4.
Current limitation is provided by the primary circuit for each
power train and limits the possible output power for each pair
of outputs. In the case of an overload on either of the power
trains, which causes the output voltage to fall less than
typically 60% of
V
o nom
, the entire converter will shut down and
automatically restart in short intervals (hiccup mode).
The incorporated overtemperature protection shuts down the
converter in excessive overload conditions with automatic
restart.
03098a
Vi+
4
PUL
1
Trim/Trim1
5
W
6
Ref
7
SD
8
Vi–
2
n.c.
3
PWM
16
Vo1+
15
Vo1–
17
Vo4+
18
Vo4–
13
Vo2+
14
Vo2–
12
Vo3+
11
Vo3–
19
n.c.
Fig. 1
Block diagram of quad-output models
BCD20009-G Rev AC, 06-May-2013
Page 3 of 15
POWER-ONE [ POWER-ONE ]
