
Single Output
RBC Models
Features
48V
IN
, 12V/25A Output
Quarter Brick, Regulated Bus Converter
Optimized for distributed power Intermediate Bus Architectures (IBA), the RBC-
12/25-D48 DC/DC bus converter series offer partially regulated outputs (±2.5%,
line and load) in an industry-standard quarter brick open frame package at excel-
lent prices. The present trend in distributed power architectures (DPA) requires both
high efficiency and some regulation of the output voltage to reduce the risk of under
voltage dropout. Earlier unregulated bus converters were simply ratiometric “DC
transformers.”
The fully isolated (1500Vdc) RBC series accept a wide range 36 to 75 Volt DC
input (48V nominal) and convert it to an output of 12Vdc at 25 Amps maximum. This
output then drives point-of-load (POL) converters such as our LSN, LEN, LSM or
LQN series which feature precise load regulation. Applications include 48V-powered
datacom and telecom installations, base stations, cellular telephone repeaters and
embedded systems. Wideband output ripple and noise is a low 35mVp-p. Low overall
height of 0.39" (9.9 mm) fits tight card cages.
The RBC’s synchronous-rectifier topology and fixed frequency operation means
excellent efficiencies up to 93%, enabling “no heatsink” operation for most applica-
tions up to +70°C (400 LFM airflow). “No fan” or zero airflow applications may use the
optional base plate for cold surface mounting or natural-convection heatsinks.
A wealth of electronic protection features include input undervoltage (UV) lockout,
output current limit, short circuit hiccup, overtemperature shutdown and output
overvoltage. Available options include positive or negative polarity remote On/Off
control and the baseplate. Assembled using ISO-certified automated surface-mount
techniques, the RBC series includes all FCC, UL, and IEC emissions, safety and
flammability certifications.
■
Up to 300 Watts total output power
■
To
93% Ultra-high efficiency @ full load
■
48V Input ( up to 36-75V range)
■
12V/25A Output for Intermediate Bus
Architectures with POL converters
■
Synchronous-rectifier topology
■
300kHz fixed switching frequency
■
Fully isolated, 1500V (BASIC)
■
Low 35mVp-p ripple/noise
■
2.3" x 1.45" x 0.39" quarter brick
■
Stable no-load condition
■
Thermal shutdown
■
Fully I/O protected
■
IEC/EN/UL/cUL60950 certification
pending
Figure 1. Simplified Schematic
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PRELIMINARY
www.cd4power.com
RBC Series
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