bcp50w Murata Manufacturing Co., Ltd, bcp50w Datasheet - Page 6

• Manufacturer Part Number: bcp50w
• Description: 50 Watt Dc/dc Converters
• Manufacturer: Murata Manufacturing Co., Ltd

Output Overvoltage Protection
Each voltage output of the BCP Series converter is independently monitored via
an output comparator. If the output voltage should rise to a level which could
be damaging to the load circuitry (see Performance/Functional Specifi cations
for limits), the overvoltage circuitry will power down the PWM controller caus-
ing the output voltages to collapse. Following a time out period the converter
will restart. If the fault condition persists the PWM will again power down and
the cycle will repeat. This on/off cycling is referred to as a "hiccup-mode."
Case Connection
BCP DC/DC's do not connect the metal baseplate to an internal voltage. The
"uncommitted" baseplate is connected to pin 2 which, depending upon your
system confi guration, should be connected to either +Input (pin 4), –Input (pin
1), Output Return (pins 6 & 9), or earth ground.
Thermal Shutdown
The BCP Series is equipped with Thermal Shutdown circuitry. If environmental
conditions cause the internal temperature of the DC/DC converter to rise
above the designed operating temperature (see Performance/Functional Speci-
fi cations), a precision temperature sensor will power down the unit. When the
internal temperature decreases below the threshold of the temperature sensor
the unit will self-start.
Input Reverse-Polarity Protection
Upon applying a reverse-polarity voltage to the DC/DC converter, an internal
diode will be forward biased and draw excessive current from the power
source. Therefore, it is required that the input current be limited be either an
appropriately rated input fuse or a current limited power source.
Threaded Inserts and Heatsink Installation
CAUTION: Do not use the threaded inserts to bolt the converter down to a PC
board. That will place unnecessary force on the mounting pins. Instead, the
converter is held securely by only soldering the mounting pins.
torque of 2 inch-pounds (0.23 N-m) on the M3 bolts to avoid damaging the
threaded inserts. Use a tiny amount of fastener adhesive or M3 lockwashers to
secure the bolts.
Soldering Guidelines
Murata Power Solutions recommends the specifi cations below when installing these
converters. These specifi cations vary depending on the solder type. Exceeding these
specifi cations may cause damage to the product. Be cautious when there is high atmo-
spheric humidity. We strongly recommend a mild pre-bake (100° C. for 30 minutes). Your
production environment may differ; therefore please thoroughly review these guidelines
with your process engineers.
For Sn/Ag/Cu based solders:
Maximum Preheat Temperature
Maximum Pot Temperature
Maximum Solder Dwell Time
For Sn/Pb based solders:
Maximum Preheat Temperature
Maximum Pot Temperature
Maximum Solder Dwell Time
Wave Solder Operations for through-hole mounted products (THMT)
When attaching the heat sink from above the converter, use a maximum
115° C.
270° C.
7 seconds
105° C.
250° C.
6 seconds
www.murata-ps.com
Heat Sinks for BCP Series
MPS offers two standard heat sinks that can be mounted to the half-brick
package to extend the converter's operating temperature range. Along with the
standard 2.3" x 2.4" x 0.5" (HS-CP) heat sink, MPS has designed a low-profi le
heat sink for height-restricted applications. This new heat sink (HS-CPLP2)
is designed with radiant fi ns that extend 0.51" beyond either side of the 2.4"
dimension of the BCP package. The convenience of this design is that the fi nned
extensions protrude only 0.31" below the top surface of the DC/DC converter,
allowing components with a profi le height less than 0.2" to be mounted on
the pc board below the heat sink. Therefore, while the surface area of the low-
profi le heat sink measures 2.3" x 3.5", pcb real estate is unaffected.
low-profi le heat sink should be mounted with the fi ns vertically oriented. Both
models are shipped with 0.009" self-adhesive thermal pad and mounting
screws.
For optimum thermal performance in a natural convection application, the
Note:
Figure 2. HS-CP and HS-CPLP2 Heat Sink Performance Vs. Air Flow
6
5
4
3
2
1
0
0
When mounting the heat sink to the BCP converter:
1. Maximum applied torque is 2 in-lbs.
2. Minimum thread engagement of the mounting screws is
12mm deep.
Dual Output BCP Models
100
Technical enquiries email: [e-mail], tel:
200
HS-CP
AIR VELOCITY (FT./MIN.)
300
50 Watt DC/DC Converters
3.3 and 2.5V, Half-Brick
400
MDC_BCP Models.B03 Page 6 of 7
HS-CPLP2
500
600
[phone]
700