PAQ Datasheet, PDF (15/16 Pages) Murata Manufacturing Co., Ltd. – Up to 150W 29.8V Nom Output Quarter-Brick Isolated DC-DC Converter with 2:1 Wide Input Range

PAQ Series
Up to 150W 29.8V Nom Output Quarter-Brick Isolated
DC-DC Converter with 2:1 Wide Input Range
your applications by observing the converter’s output transient response during
step loads. There should not be any appreciable ringing or oscillation. You
may also adjust the output trim slightly to compensate for voltage loss in any
+VCC
external filter elements. Do not exceed maximum power ratings.
Please observe Sense inputs tolerance to avoid improper operation:
[Vout(+) −Vout(-)] − [Sense(+) −Sense(-)] ≤ 10% of Vout
ON/OFF
CONTROL
Output overvoltage protection is monitored at the output voltage pin, not the
Sense pin. Therefore excessive voltage differences between Vout and Sense
-Vin
together with trim adjustment of the output can cause the overvoltage protec-
tion circuit to activate and shut down the output.
Power derating of the converter is based on the combination of maximum
output current and the highest output voltage. Therefore the designer must
ensure:
(Vout at pins) x (Iout) ≤ (Max. rated output power)
Remote On/Off Control
On the input side, a remote On/Off Control can be specified with either positive
or negative logic as follows:
Models are on (enabled) when the On/Off is grounded or brought to within
a low voltage (see Specifications) with respect to –VIN. The device is off
(disabled) when the On/Off is left open or is pulled high to +13.5VDC Max. with
respect to –VIN.
Figure 7. Driving the On/Off Control Pin (suggested circuit)
Cold Wall Cooling Test Method (cold baseplate applications)
Murata Power Solutions’ cold wall cooling test is implemented with the
baseplate of the UUT (unit under test) mounted to the large aluminum block
(see figure 8). Thermocouples are attached to the known hot spots on the UUT
as well as the aluminum block and still air space. The environment chamber
regulates the aluminum block and baseplate temperature at a fixed value up
to 100°C. The still air chamber is manually regulated to 85°C by the attached
heaters. Output load is applied to the UUT and it is monitored to ensure safe
operating limits at all input voltages.
Dynamic control of the On/Off function should be able to sink the specified
signal current when brought low and withstand specified voltage when brought
high. Be aware too that there is a finite time in milliseconds (see Specifications)
between the time of On/Off Control activation and stable, regulated output. This
time will vary slightly with output load type and current and input conditions.
There are two CAUTIONs for the On/Off Control:
CAUTION: While it is possible to control the On/Off with external logic if you
carefully observe the voltage levels, the preferred circuit is either an open
drain/open collector transistor or a relay (which can thereupon be controlled
by logic). The On/Off prefers to be set at approx. +13.5V (open pin) for the ON
state, assuming positive logic.
Still air chamber
thermocouple
Still air chamber
Still air chamber
heater
Thermal insulation
Unit under test
Still air chamber
heater
Environment
chamber
Thermocouple
Aluminum block
CAUTION: Do not apply voltages to the On/Off pin when there is no input power
voltage. Otherwise the converter may be permanently damaged.
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Figure 8. Cold Wall Test Fixture Equipment
MDC_PAQ Series.A02 Page 15 of 16