LSM2-T/6-W3N-C Murata Power Solutions Inc, LSM2-T/6-W3N-C Datasheet - Page 10

• Manufacturer Part Number: LSM2-T/6-W3N-C
• Description: CONV DC/DC 19.8W 6A 5V SMD
• Manufacturer: Murata Power Solutions Inc
• Series: LSM2r
• Type: Point of Load (POL) Non-Isolatedr

Specifications of LSM2-T/6-W3N-C

• Output: 0.75 ~ 3.3V
• Number Of Outputs: 1
• Power (watts): 19W
• Mounting Type: Surface Mount
• Voltage - Input: 2.4 ~ 5.5V
• Package / Case: 8-DIP SMD Module
• 1st Output: 0.75 ~ 3.3 VDC @ 6A
• Size / Dimension: 1.30" L x 0.53" W x 0.34" H (33mm x 13.5mm x 8.6mm)
• Power (watts) - Rated: 19.8W
• Operating Temperature: -40°C ~ 85°C
• Efficiency: 95.5%
• Approvals: CSA, cUL, EN, UL
• Dc / Dc Converter O/p Type: Variable
• No. Of Outputs: 1
• Input Voltage: 2.4V To 5.5V
• Power Rating: 19.8W
• Output Voltage: 5V
• Output Current: 6A
• Approval Bodies: UL, CSA
• Supply Voltage: 5V
• Product: Non-Isolated / POL
• Output Power: 20 W
• Input Voltage Range: 2.4 V to 5.5 V
• Output Voltage (channel 1): 0.75 V to 3.3 V
• Output Current (channel 1): 6 A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• 3rd Output: -
• 2nd Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 811-1782-2

Tape & Reel Surface Mount Package
MPS’s LSM2 series DC/DC converters are the only higher-current (16A) SMT
DC/DC's that can be automatically “pick-and-placed” using standard vacuum-
pickup equipment (nozzle size and style, vacuum pressure and placement
speed may need to be optimized for automated pick and place) and subse-
quently refl owed using high-temperature, lead-free solder.
sembled by their vendors with high-temperature solder (usually Sn96.5/Ag3.5
with a melting point +221°C) so that you may attach them to your board using
low-temperature solder (usually Sn63/Pb37 with a melting point of +183°C).
Conceptually straightforward, this "stepped" solder approach has its limita-
tions, and it is clearly out of step with an industry trending toward the broad
use of lead-free solders. Are you to experiment and develop refl ow profi les
from other vendors that ensure the components on those DC/DC never exceed
215-216°C? If those components get too hot, "double-refl ow" could compro-
mise the reliability of their solder joints. Virtually all these devices demand you
"cool down" the Sn63 profi le you are likely using today.
Virtually all SMT DC/DCs today are unprotected "open-frame" devices as-
250
200
183
150
100
221
50
0
50
Sn96.5/Ag3.5 Melting Point
Sn63/Pb37 Melting Point
100
PCB TEMPERATURE INSIDE THE HEAT SHIELD
150
www.murata-ps.com
Figure 6. Refl ow Solder Profi le
Time (Seconds)
200
magic solders no one else has. Nevertheless, we have a simple and practical,
straightforward approach that works. We assemble our LSM2 SMT DC/DC's
using a high-temperature (+216°C), lead-free alloy (Sn96.2%, Ag2.5%, Cu0.8%,
Sb0.5%). The LSM2 design ensures co-planarity to within 0.004 inches
(100μ1m) of the unit's tin-plated (150 micro-inches) copper leads. See Me-
chanical Data for additional information.
ing the package leads, provides thermal insulation to internal components
during refl ow and its smooth surface ideally doubles as the vacuum pick-up
location also. The insulation properties of the heat shield are so effective
that temperature differentials as high as 50°C develop inside-to-outside the
shield. Oven temperature profi les with peaks of 250-260°C and dwell times
exceeding 2 minutes above 221°C (the melting point of Sn96.5/Ag3.5) are
easily achieved.
MPS is not exempted from the Laws of Physics, and we do not have
The disposable heat shield (patent pending), which has a cutaway expos-
250
HEAT SHIELD OUTSIDE TEMPERATURE
Selectable-Output POL DC/DC Converters
25 Jun 2010
300
Single Output, Non-Isolated
MDC_LSM2
350
LSM2 Series
email: [e-mail]
Series.B09Δ
400
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